Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2019-11-02

The following pull-request contains BPF updates for your *net-next* tree.

We've added 30 non-merge commits during the last 7 day(s) which contain
a total of 41 files changed, 1864 insertions(+), 474 deletions(-).

The main changes are:

1) Fix long standing user vs kernel access issue by introducing
   bpf_probe_read_user() and bpf_probe_read_kernel() helpers, from Daniel.

2) Accelerated xskmap lookup, from Björn and Maciej.

3) Support for automatic map pinning in libbpf, from Toke.

4) Cleanup of BTF-enabled raw tracepoints, from Alexei.

5) Various fixes to libbpf and selftests.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2019-11-02 15:27:42 -07:00
commit ae8a76fb8b
41 changed files with 1864 additions and 477 deletions

View File

@ -47,6 +47,15 @@ Program types
prog_flow_dissector
Testing BPF
===========
.. toctree::
:maxdepth: 1
s390
.. Links:
.. _Documentation/networking/filter.txt: ../networking/filter.txt
.. _man-pages: https://www.kernel.org/doc/man-pages/

205
Documentation/bpf/s390.rst Normal file
View File

@ -0,0 +1,205 @@
===================
Testing BPF on s390
===================
1. Introduction
***************
IBM Z are mainframe computers, which are descendants of IBM System/360 from
year 1964. They are supported by the Linux kernel under the name "s390". This
document describes how to test BPF in an s390 QEMU guest.
2. One-time setup
*****************
The following is required to build and run the test suite:
* s390 GCC
* s390 development headers and libraries
* Clang with BPF support
* QEMU with s390 support
* Disk image with s390 rootfs
Debian supports installing compiler and libraries for s390 out of the box.
Users of other distros may use debootstrap in order to set up a Debian chroot::
sudo debootstrap \
--variant=minbase \
--include=sudo \
testing \
./s390-toolchain
sudo mount --rbind /dev ./s390-toolchain/dev
sudo mount --rbind /proc ./s390-toolchain/proc
sudo mount --rbind /sys ./s390-toolchain/sys
sudo chroot ./s390-toolchain
Once on Debian, the build prerequisites can be installed as follows::
sudo dpkg --add-architecture s390x
sudo apt-get update
sudo apt-get install \
bc \
bison \
cmake \
debootstrap \
dwarves \
flex \
g++ \
gcc \
g++-s390x-linux-gnu \
gcc-s390x-linux-gnu \
gdb-multiarch \
git \
make \
python3 \
qemu-system-misc \
qemu-utils \
rsync \
libcap-dev:s390x \
libelf-dev:s390x \
libncurses-dev
Latest Clang targeting BPF can be installed as follows::
git clone https://github.com/llvm/llvm-project.git
ln -s ../../clang llvm-project/llvm/tools/
mkdir llvm-project-build
cd llvm-project-build
cmake \
-DLLVM_TARGETS_TO_BUILD=BPF \
-DCMAKE_BUILD_TYPE=Release \
-DCMAKE_INSTALL_PREFIX=/opt/clang-bpf \
../llvm-project/llvm
make
sudo make install
export PATH=/opt/clang-bpf/bin:$PATH
The disk image can be prepared using a loopback mount and debootstrap::
qemu-img create -f raw ./s390.img 1G
sudo losetup -f ./s390.img
sudo mkfs.ext4 /dev/loopX
mkdir ./s390.rootfs
sudo mount /dev/loopX ./s390.rootfs
sudo debootstrap \
--foreign \
--arch=s390x \
--variant=minbase \
--include=" \
iproute2, \
iputils-ping, \
isc-dhcp-client, \
kmod, \
libcap2, \
libelf1, \
netcat, \
procps" \
testing \
./s390.rootfs
sudo umount ./s390.rootfs
sudo losetup -d /dev/loopX
3. Compilation
**************
In addition to the usual Kconfig options required to run the BPF test suite, it
is also helpful to select::
CONFIG_NET_9P=y
CONFIG_9P_FS=y
CONFIG_NET_9P_VIRTIO=y
CONFIG_VIRTIO_PCI=y
as that would enable a very easy way to share files with the s390 virtual
machine.
Compiling kernel, modules and testsuite, as well as preparing gdb scripts to
simplify debugging, can be done using the following commands::
make ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- menuconfig
make ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- bzImage modules scripts_gdb
make ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- \
-C tools/testing/selftests \
TARGETS=bpf \
INSTALL_PATH=$PWD/tools/testing/selftests/kselftest_install \
install
4. Running the test suite
*************************
The virtual machine can be started as follows::
qemu-system-s390x \
-cpu max,zpci=on \
-smp 2 \
-m 4G \
-kernel linux/arch/s390/boot/compressed/vmlinux \
-drive file=./s390.img,if=virtio,format=raw \
-nographic \
-append 'root=/dev/vda rw console=ttyS1' \
-virtfs local,path=./linux,security_model=none,mount_tag=linux \
-object rng-random,filename=/dev/urandom,id=rng0 \
-device virtio-rng-ccw,rng=rng0 \
-netdev user,id=net0 \
-device virtio-net-ccw,netdev=net0
When using this on a real IBM Z, ``-enable-kvm`` may be added for better
performance. When starting the virtual machine for the first time, disk image
setup must be finalized using the following command::
/debootstrap/debootstrap --second-stage
Directory with the code built on the host as well as ``/proc`` and ``/sys``
need to be mounted as follows::
mkdir -p /linux
mount -t 9p linux /linux
mount -t proc proc /proc
mount -t sysfs sys /sys
After that, the test suite can be run using the following commands::
cd /linux/tools/testing/selftests/kselftest_install
./run_kselftest.sh
As usual, tests can be also run individually::
cd /linux/tools/testing/selftests/bpf
./test_verifier
5. Debugging
************
It is possible to debug the s390 kernel using QEMU GDB stub, which is activated
by passing ``-s`` to QEMU.
It is preferable to turn KASLR off, so that gdb would know where to find the
kernel image in memory, by building the kernel with::
RANDOMIZE_BASE=n
GDB can then be attached using the following command::
gdb-multiarch -ex 'target remote localhost:1234' ./vmlinux
6. Network
**********
In case one needs to use the network in the virtual machine in order to e.g.
install additional packages, it can be configured using::
dhclient eth0
7. Links
********
This document is a compilation of techniques, whose more comprehensive
descriptions can be found by following these links:
- `Debootstrap <https://wiki.debian.org/EmDebian/CrossDebootstrap>`_
- `Multiarch <https://wiki.debian.org/Multiarch/HOWTO>`_
- `Building LLVM <https://llvm.org/docs/CMake.html>`_
- `Cross-compiling the kernel <https://wiki.gentoo.org/wiki/Embedded_Handbook/General/Cross-compiling_the_kernel>`_
- `QEMU s390x Guest Support <https://wiki.qemu.org/Documentation/Platforms/S390X>`_
- `Plan 9 folder sharing over Virtio <https://wiki.qemu.org/Documentation/9psetup>`_
- `Using GDB with QEMU <https://wiki.osdev.org/Kernel_Debugging#Use_GDB_with_QEMU>`_

View File

@ -13,7 +13,7 @@ CFLAGS_REMOVE_mem_encrypt_identity.o = -pg
endif
obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
pat.o pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o
pat.o pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o maccess.o
# Make sure __phys_addr has no stackprotector
nostackp := $(call cc-option, -fno-stack-protector)

43
arch/x86/mm/maccess.c Normal file
View File

@ -0,0 +1,43 @@
// SPDX-License-Identifier: GPL-2.0-only
#include <linux/uaccess.h>
#include <linux/kernel.h>
#ifdef CONFIG_X86_64
static __always_inline u64 canonical_address(u64 vaddr, u8 vaddr_bits)
{
return ((s64)vaddr << (64 - vaddr_bits)) >> (64 - vaddr_bits);
}
static __always_inline bool invalid_probe_range(u64 vaddr)
{
/*
* Range covering the highest possible canonical userspace address
* as well as non-canonical address range. For the canonical range
* we also need to include the userspace guard page.
*/
return vaddr < TASK_SIZE_MAX + PAGE_SIZE ||
canonical_address(vaddr, boot_cpu_data.x86_virt_bits) != vaddr;
}
#else
static __always_inline bool invalid_probe_range(u64 vaddr)
{
return vaddr < TASK_SIZE_MAX;
}
#endif
long probe_kernel_read_strict(void *dst, const void *src, size_t size)
{
if (unlikely(invalid_probe_range((unsigned long)src)))
return -EFAULT;
return __probe_kernel_read(dst, src, size);
}
long strncpy_from_unsafe_strict(char *dst, const void *unsafe_addr, long count)
{
if (unlikely(invalid_probe_range((unsigned long)unsafe_addr)))
return -EFAULT;
return __strncpy_from_unsafe(dst, unsafe_addr, count);
}

View File

@ -373,6 +373,11 @@ enum bpf_cgroup_storage_type {
#define MAX_BPF_CGROUP_STORAGE_TYPE __BPF_CGROUP_STORAGE_MAX
/* The longest tracepoint has 12 args.
* See include/trace/bpf_probe.h
*/
#define MAX_BPF_FUNC_ARGS 12
struct bpf_prog_stats {
u64 cnt;
u64 nsecs;
@ -1004,31 +1009,6 @@ static inline int sock_map_get_from_fd(const union bpf_attr *attr,
}
#endif
#if defined(CONFIG_XDP_SOCKETS)
struct xdp_sock;
struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map, u32 key);
int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp,
struct xdp_sock *xs);
void __xsk_map_flush(struct bpf_map *map);
#else
struct xdp_sock;
static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map,
u32 key)
{
return NULL;
}
static inline int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp,
struct xdp_sock *xs)
{
return -EOPNOTSUPP;
}
static inline void __xsk_map_flush(struct bpf_map *map)
{
}
#endif
#if defined(CONFIG_INET) && defined(CONFIG_BPF_SYSCALL)
void bpf_sk_reuseport_detach(struct sock *sk);
int bpf_fd_reuseport_array_lookup_elem(struct bpf_map *map, void *key,

View File

@ -26,6 +26,7 @@ BPF_PROG_TYPE(BPF_PROG_TYPE_TRACEPOINT, tracepoint)
BPF_PROG_TYPE(BPF_PROG_TYPE_PERF_EVENT, perf_event)
BPF_PROG_TYPE(BPF_PROG_TYPE_RAW_TRACEPOINT, raw_tracepoint)
BPF_PROG_TYPE(BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE, raw_tracepoint_writable)
BPF_PROG_TYPE(BPF_PROG_TYPE_TRACING, tracing)
#endif
#ifdef CONFIG_CGROUP_BPF
BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_DEVICE, cg_dev)

View File

@ -311,6 +311,7 @@ copy_struct_from_user(void *dst, size_t ksize, const void __user *src,
* happens, handle that and return -EFAULT.
*/
extern long probe_kernel_read(void *dst, const void *src, size_t size);
extern long probe_kernel_read_strict(void *dst, const void *src, size_t size);
extern long __probe_kernel_read(void *dst, const void *src, size_t size);
/*
@ -337,7 +338,22 @@ extern long __probe_user_read(void *dst, const void __user *src, size_t size);
extern long notrace probe_kernel_write(void *dst, const void *src, size_t size);
extern long notrace __probe_kernel_write(void *dst, const void *src, size_t size);
/*
* probe_user_write(): safely attempt to write to a location in user space
* @dst: address to write to
* @src: pointer to the data that shall be written
* @size: size of the data chunk
*
* Safely write to address @dst from the buffer at @src. If a kernel fault
* happens, handle that and return -EFAULT.
*/
extern long notrace probe_user_write(void __user *dst, const void *src, size_t size);
extern long notrace __probe_user_write(void __user *dst, const void *src, size_t size);
extern long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count);
extern long strncpy_from_unsafe_strict(char *dst, const void *unsafe_addr,
long count);
extern long __strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count);
extern long strncpy_from_unsafe_user(char *dst, const void __user *unsafe_addr,
long count);
extern long strnlen_unsafe_user(const void __user *unsafe_addr, long count);

View File

@ -69,7 +69,14 @@ struct xdp_umem {
/* Nodes are linked in the struct xdp_sock map_list field, and used to
* track which maps a certain socket reside in.
*/
struct xsk_map;
struct xsk_map {
struct bpf_map map;
struct list_head __percpu *flush_list;
spinlock_t lock; /* Synchronize map updates */
struct xdp_sock *xsk_map[];
};
struct xsk_map_node {
struct list_head node;
struct xsk_map *map;
@ -109,8 +116,6 @@ struct xdp_sock {
struct xdp_buff;
#ifdef CONFIG_XDP_SOCKETS
int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
void xsk_flush(struct xdp_sock *xs);
bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs);
/* Used from netdev driver */
bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt);
@ -134,6 +139,22 @@ void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs,
struct xdp_sock **map_entry);
int xsk_map_inc(struct xsk_map *map);
void xsk_map_put(struct xsk_map *map);
int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp,
struct xdp_sock *xs);
void __xsk_map_flush(struct bpf_map *map);
static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map,
u32 key)
{
struct xsk_map *m = container_of(map, struct xsk_map, map);
struct xdp_sock *xs;
if (key >= map->max_entries)
return NULL;
xs = READ_ONCE(m->xsk_map[key]);
return xs;
}
static inline u64 xsk_umem_extract_addr(u64 addr)
{
@ -224,15 +245,6 @@ static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
return -ENOTSUPP;
}
static inline int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
{
return -ENOTSUPP;
}
static inline void xsk_flush(struct xdp_sock *xs)
{
}
static inline bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs)
{
return false;
@ -357,6 +369,21 @@ static inline u64 xsk_umem_adjust_offset(struct xdp_umem *umem, u64 handle,
return 0;
}
static inline int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp,
struct xdp_sock *xs)
{
return -EOPNOTSUPP;
}
static inline void __xsk_map_flush(struct bpf_map *map)
{
}
static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map,
u32 key)
{
return NULL;
}
#endif /* CONFIG_XDP_SOCKETS */
#endif /* _LINUX_XDP_SOCK_H */

View File

@ -173,6 +173,7 @@ enum bpf_prog_type {
BPF_PROG_TYPE_CGROUP_SYSCTL,
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
BPF_PROG_TYPE_CGROUP_SOCKOPT,
BPF_PROG_TYPE_TRACING,
};
enum bpf_attach_type {
@ -199,6 +200,7 @@ enum bpf_attach_type {
BPF_CGROUP_UDP6_RECVMSG,
BPF_CGROUP_GETSOCKOPT,
BPF_CGROUP_SETSOCKOPT,
BPF_TRACE_RAW_TP,
__MAX_BPF_ATTACH_TYPE
};
@ -561,10 +563,13 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read(void *dst, u32 size, const void *src)
* int bpf_probe_read(void *dst, u32 size, const void *unsafe_ptr)
* Description
* For tracing programs, safely attempt to read *size* bytes from
* address *src* and store the data in *dst*.
* kernel space address *unsafe_ptr* and store the data in *dst*.
*
* Generally, use bpf_probe_read_user() or bpf_probe_read_kernel()
* instead.
* Return
* 0 on success, or a negative error in case of failure.
*
@ -1426,45 +1431,14 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
* int bpf_probe_read_str(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Copy a NUL terminated string from an unsafe address
* *unsafe_ptr* to *dst*. The *size* should include the
* terminating NUL byte. In case the string length is smaller than
* *size*, the target is not padded with further NUL bytes. If the
* string length is larger than *size*, just *size*-1 bytes are
* copied and the last byte is set to NUL.
* Copy a NUL terminated string from an unsafe kernel address
* *unsafe_ptr* to *dst*. See bpf_probe_read_kernel_str() for
* more details.
*
* On success, the length of the copied string is returned. This
* makes this helper useful in tracing programs for reading
* strings, and more importantly to get its length at runtime. See
* the following snippet:
*
* ::
*
* SEC("kprobe/sys_open")
* void bpf_sys_open(struct pt_regs *ctx)
* {
* char buf[PATHLEN]; // PATHLEN is defined to 256
* int res = bpf_probe_read_str(buf, sizeof(buf),
* ctx->di);
*
* // Consume buf, for example push it to
* // userspace via bpf_perf_event_output(); we
* // can use res (the string length) as event
* // size, after checking its boundaries.
* }
*
* In comparison, using **bpf_probe_read()** helper here instead
* to read the string would require to estimate the length at
* compile time, and would often result in copying more memory
* than necessary.
*
* Another useful use case is when parsing individual process
* arguments or individual environment variables navigating
* *current*\ **->mm->arg_start** and *current*\
* **->mm->env_start**: using this helper and the return value,
* one can quickly iterate at the right offset of the memory area.
* Generally, use bpf_probe_read_user_str() or bpf_probe_read_kernel_str()
* instead.
* Return
* On success, the strictly positive length of the string,
* including the trailing NUL character. On error, a negative
@ -2775,6 +2749,72 @@ union bpf_attr {
* restricted to raw_tracepoint bpf programs.
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read_user(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Safely attempt to read *size* bytes from user space address
* *unsafe_ptr* and store the data in *dst*.
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Safely attempt to read *size* bytes from kernel space address
* *unsafe_ptr* and store the data in *dst*.
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read_user_str(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Copy a NUL terminated string from an unsafe user address
* *unsafe_ptr* to *dst*. The *size* should include the
* terminating NUL byte. In case the string length is smaller than
* *size*, the target is not padded with further NUL bytes. If the
* string length is larger than *size*, just *size*-1 bytes are
* copied and the last byte is set to NUL.
*
* On success, the length of the copied string is returned. This
* makes this helper useful in tracing programs for reading
* strings, and more importantly to get its length at runtime. See
* the following snippet:
*
* ::
*
* SEC("kprobe/sys_open")
* void bpf_sys_open(struct pt_regs *ctx)
* {
* char buf[PATHLEN]; // PATHLEN is defined to 256
* int res = bpf_probe_read_user_str(buf, sizeof(buf),
* ctx->di);
*
* // Consume buf, for example push it to
* // userspace via bpf_perf_event_output(); we
* // can use res (the string length) as event
* // size, after checking its boundaries.
* }
*
* In comparison, using **bpf_probe_read_user()** helper here
* instead to read the string would require to estimate the length
* at compile time, and would often result in copying more memory
* than necessary.
*
* Another useful use case is when parsing individual process
* arguments or individual environment variables navigating
* *current*\ **->mm->arg_start** and *current*\
* **->mm->env_start**: using this helper and the return value,
* one can quickly iterate at the right offset of the memory area.
* Return
* On success, the strictly positive length of the string,
* including the trailing NUL character. On error, a negative
* value.
*
* int bpf_probe_read_kernel_str(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Copy a NUL terminated string from an unsafe kernel address *unsafe_ptr*
* to *dst*. Same semantics as with bpf_probe_read_user_str() apply.
* Return
* On success, the strictly positive length of the string, including
* the trailing NUL character. On error, a negative value.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@ -2888,7 +2928,11 @@ union bpf_attr {
FN(sk_storage_delete), \
FN(send_signal), \
FN(tcp_gen_syncookie), \
FN(skb_output),
FN(skb_output), \
FN(probe_read_user), \
FN(probe_read_kernel), \
FN(probe_read_user_str), \
FN(probe_read_kernel_str),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call

View File

@ -668,9 +668,6 @@ static struct bpf_prog *bpf_prog_kallsyms_find(unsigned long addr)
{
struct latch_tree_node *n;
if (!bpf_jit_kallsyms_enabled())
return NULL;
n = latch_tree_find((void *)addr, &bpf_tree, &bpf_tree_ops);
return n ?
container_of(n, struct bpf_prog_aux, ksym_tnode)->prog :
@ -1309,11 +1306,12 @@ bool bpf_opcode_in_insntable(u8 code)
}
#ifndef CONFIG_BPF_JIT_ALWAYS_ON
u64 __weak bpf_probe_read(void * dst, u32 size, const void * unsafe_ptr)
u64 __weak bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr)
{
memset(dst, 0, size);
return -EFAULT;
}
/**
* __bpf_prog_run - run eBPF program on a given context
* @regs: is the array of MAX_BPF_EXT_REG eBPF pseudo-registers
@ -1571,7 +1569,7 @@ static u64 __no_fgcse ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u6
#undef LDST
#define LDX_PROBE(SIZEOP, SIZE) \
LDX_PROBE_MEM_##SIZEOP: \
bpf_probe_read(&DST, SIZE, (const void *)(long) SRC); \
bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) SRC); \
CONT;
LDX_PROBE(B, 1)
LDX_PROBE(H, 2)

View File

@ -1579,7 +1579,7 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
u32 btf_id)
{
switch (prog_type) {
case BPF_PROG_TYPE_RAW_TRACEPOINT:
case BPF_PROG_TYPE_TRACING:
if (btf_id > BTF_MAX_TYPE)
return -EINVAL;
break;
@ -1842,13 +1842,13 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
return PTR_ERR(prog);
if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
prog->type != BPF_PROG_TYPE_TRACING &&
prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
err = -EINVAL;
goto out_put_prog;
}
if (prog->type == BPF_PROG_TYPE_RAW_TRACEPOINT &&
prog->aux->attach_btf_id) {
if (prog->type == BPF_PROG_TYPE_TRACING) {
if (attr->raw_tracepoint.name) {
/* raw_tp name should not be specified in raw_tp
* programs that were verified via in-kernel BTF info

View File

@ -6279,6 +6279,11 @@ static int check_return_code(struct bpf_verifier_env *env)
case BPF_PROG_TYPE_CGROUP_SYSCTL:
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
break;
case BPF_PROG_TYPE_RAW_TRACEPOINT:
if (!env->prog->aux->attach_btf_id)
return 0;
range = tnum_const(0);
break;
default:
return 0;
}
@ -9376,24 +9381,36 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
{
struct bpf_prog *prog = env->prog;
u32 btf_id = prog->aux->attach_btf_id;
const char prefix[] = "btf_trace_";
const struct btf_type *t;
const char *tname;
if (prog->type == BPF_PROG_TYPE_RAW_TRACEPOINT && btf_id) {
const char prefix[] = "btf_trace_";
if (prog->type != BPF_PROG_TYPE_TRACING)
return 0;
if (!btf_id) {
verbose(env, "Tracing programs must provide btf_id\n");
return -EINVAL;
}
t = btf_type_by_id(btf_vmlinux, btf_id);
if (!t) {
verbose(env, "attach_btf_id %u is invalid\n", btf_id);
return -EINVAL;
}
tname = btf_name_by_offset(btf_vmlinux, t->name_off);
if (!tname) {
verbose(env, "attach_btf_id %u doesn't have a name\n", btf_id);
return -EINVAL;
}
switch (prog->expected_attach_type) {
case BPF_TRACE_RAW_TP:
if (!btf_type_is_typedef(t)) {
verbose(env, "attach_btf_id %u is not a typedef\n",
btf_id);
return -EINVAL;
}
tname = btf_name_by_offset(btf_vmlinux, t->name_off);
if (!tname || strncmp(prefix, tname, sizeof(prefix) - 1)) {
if (strncmp(prefix, tname, sizeof(prefix) - 1)) {
verbose(env, "attach_btf_id %u points to wrong type name %s\n",
btf_id, tname);
return -EINVAL;
@ -9414,8 +9431,10 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
prog->aux->attach_func_name = tname;
prog->aux->attach_func_proto = t;
prog->aux->attach_btf_trace = true;
}
return 0;
default:
return -EINVAL;
}
}
int bpf_check(struct bpf_prog **prog, union bpf_attr *attr,

View File

@ -9,13 +9,6 @@
#include <linux/slab.h>
#include <linux/sched.h>
struct xsk_map {
struct bpf_map map;
struct xdp_sock **xsk_map;
struct list_head __percpu *flush_list;
spinlock_t lock; /* Synchronize map updates */
};
int xsk_map_inc(struct xsk_map *map)
{
struct bpf_map *m = &map->map;
@ -80,9 +73,10 @@ static void xsk_map_sock_delete(struct xdp_sock *xs,
static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
{
struct bpf_map_memory mem;
int cpu, err, numa_node;
struct xsk_map *m;
int cpu, err;
u64 cost;
u64 cost, size;
if (!capable(CAP_NET_ADMIN))
return ERR_PTR(-EPERM);
@ -92,44 +86,35 @@ static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
attr->map_flags & ~(BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY))
return ERR_PTR(-EINVAL);
m = kzalloc(sizeof(*m), GFP_USER);
if (!m)
numa_node = bpf_map_attr_numa_node(attr);
size = struct_size(m, xsk_map, attr->max_entries);
cost = size + array_size(sizeof(*m->flush_list), num_possible_cpus());
err = bpf_map_charge_init(&mem, cost);
if (err < 0)
return ERR_PTR(err);
m = bpf_map_area_alloc(size, numa_node);
if (!m) {
bpf_map_charge_finish(&mem);
return ERR_PTR(-ENOMEM);
}
bpf_map_init_from_attr(&m->map, attr);
bpf_map_charge_move(&m->map.memory, &mem);
spin_lock_init(&m->lock);
cost = (u64)m->map.max_entries * sizeof(struct xdp_sock *);
cost += sizeof(struct list_head) * num_possible_cpus();
/* Notice returns -EPERM on if map size is larger than memlock limit */
err = bpf_map_charge_init(&m->map.memory, cost);
if (err)
goto free_m;
err = -ENOMEM;
m->flush_list = alloc_percpu(struct list_head);
if (!m->flush_list)
goto free_charge;
if (!m->flush_list) {
bpf_map_charge_finish(&m->map.memory);
bpf_map_area_free(m);
return ERR_PTR(-ENOMEM);
}
for_each_possible_cpu(cpu)
INIT_LIST_HEAD(per_cpu_ptr(m->flush_list, cpu));
m->xsk_map = bpf_map_area_alloc(m->map.max_entries *
sizeof(struct xdp_sock *),
m->map.numa_node);
if (!m->xsk_map)
goto free_percpu;
return &m->map;
free_percpu:
free_percpu(m->flush_list);
free_charge:
bpf_map_charge_finish(&m->map.memory);
free_m:
kfree(m);
return ERR_PTR(err);
}
static void xsk_map_free(struct bpf_map *map)
@ -139,8 +124,7 @@ static void xsk_map_free(struct bpf_map *map)
bpf_clear_redirect_map(map);
synchronize_net();
free_percpu(m->flush_list);
bpf_map_area_free(m->xsk_map);
kfree(m);
bpf_map_area_free(m);
}
static int xsk_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
@ -160,45 +144,20 @@ static int xsk_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
return 0;
}
struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map, u32 key)
static u32 xsk_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
{
struct xsk_map *m = container_of(map, struct xsk_map, map);
struct xdp_sock *xs;
const int ret = BPF_REG_0, mp = BPF_REG_1, index = BPF_REG_2;
struct bpf_insn *insn = insn_buf;
if (key >= map->max_entries)
return NULL;
xs = READ_ONCE(m->xsk_map[key]);
return xs;
}
int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp,
struct xdp_sock *xs)
{
struct xsk_map *m = container_of(map, struct xsk_map, map);
struct list_head *flush_list = this_cpu_ptr(m->flush_list);
int err;
err = xsk_rcv(xs, xdp);
if (err)
return err;
if (!xs->flush_node.prev)
list_add(&xs->flush_node, flush_list);
return 0;
}
void __xsk_map_flush(struct bpf_map *map)
{
struct xsk_map *m = container_of(map, struct xsk_map, map);
struct list_head *flush_list = this_cpu_ptr(m->flush_list);
struct xdp_sock *xs, *tmp;
list_for_each_entry_safe(xs, tmp, flush_list, flush_node) {
xsk_flush(xs);
__list_del_clearprev(&xs->flush_node);
}
*insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0);
*insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 5);
*insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(sizeof(struct xsk_sock *)));
*insn++ = BPF_ALU64_IMM(BPF_ADD, mp, offsetof(struct xsk_map, xsk_map));
*insn++ = BPF_ALU64_REG(BPF_ADD, ret, mp);
*insn++ = BPF_LDX_MEM(BPF_SIZEOF(struct xsk_sock *), ret, ret, 0);
*insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1);
*insn++ = BPF_MOV64_IMM(ret, 0);
return insn - insn_buf;
}
static void *xsk_map_lookup_elem(struct bpf_map *map, void *key)
@ -312,6 +271,7 @@ const struct bpf_map_ops xsk_map_ops = {
.map_free = xsk_map_free,
.map_get_next_key = xsk_map_get_next_key,
.map_lookup_elem = xsk_map_lookup_elem,
.map_gen_lookup = xsk_map_gen_lookup,
.map_lookup_elem_sys_only = xsk_map_lookup_elem_sys_only,
.map_update_elem = xsk_map_update_elem,
.map_delete_elem = xsk_map_delete_elem,

View File

@ -138,24 +138,19 @@ static const struct bpf_func_proto bpf_override_return_proto = {
};
#endif
BPF_CALL_3(bpf_probe_read, void *, dst, u32, size, const void *, unsafe_ptr)
BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
const void __user *, unsafe_ptr)
{
int ret;
int ret = probe_user_read(dst, unsafe_ptr, size);
ret = security_locked_down(LOCKDOWN_BPF_READ);
if (ret < 0)
goto out;
ret = probe_kernel_read(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
out:
memset(dst, 0, size);
return ret;
}
static const struct bpf_func_proto bpf_probe_read_proto = {
.func = bpf_probe_read,
static const struct bpf_func_proto bpf_probe_read_user_proto = {
.func = bpf_probe_read_user,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_UNINIT_MEM,
@ -163,7 +158,128 @@ static const struct bpf_func_proto bpf_probe_read_proto = {
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_probe_write_user, void *, unsafe_ptr, const void *, src,
BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
const void __user *, unsafe_ptr)
{
int ret = strncpy_from_unsafe_user(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
memset(dst, 0, size);
return ret;
}
static const struct bpf_func_proto bpf_probe_read_user_str_proto = {
.func = bpf_probe_read_user_str,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_UNINIT_MEM,
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_ANYTHING,
};
static __always_inline int
bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr,
const bool compat)
{
int ret = security_locked_down(LOCKDOWN_BPF_READ);
if (unlikely(ret < 0))
goto out;
ret = compat ? probe_kernel_read(dst, unsafe_ptr, size) :
probe_kernel_read_strict(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
out:
memset(dst, 0, size);
return ret;
}
BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
const void *, unsafe_ptr)
{
return bpf_probe_read_kernel_common(dst, size, unsafe_ptr, false);
}
static const struct bpf_func_proto bpf_probe_read_kernel_proto = {
.func = bpf_probe_read_kernel,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_UNINIT_MEM,
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
const void *, unsafe_ptr)
{
return bpf_probe_read_kernel_common(dst, size, unsafe_ptr, true);
}
static const struct bpf_func_proto bpf_probe_read_compat_proto = {
.func = bpf_probe_read_compat,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_UNINIT_MEM,
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_ANYTHING,
};
static __always_inline int
bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr,
const bool compat)
{
int ret = security_locked_down(LOCKDOWN_BPF_READ);
if (unlikely(ret < 0))
goto out;
/*
* The strncpy_from_unsafe_*() call will likely not fill the entire
* buffer, but that's okay in this circumstance as we're probing
* arbitrary memory anyway similar to bpf_probe_read_*() and might
* as well probe the stack. Thus, memory is explicitly cleared
* only in error case, so that improper users ignoring return
* code altogether don't copy garbage; otherwise length of string
* is returned that can be used for bpf_perf_event_output() et al.
*/
ret = compat ? strncpy_from_unsafe(dst, unsafe_ptr, size) :
strncpy_from_unsafe_strict(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
out:
memset(dst, 0, size);
return ret;
}
BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
const void *, unsafe_ptr)
{
return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr, false);
}
static const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
.func = bpf_probe_read_kernel_str,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_UNINIT_MEM,
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
const void *, unsafe_ptr)
{
return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr, true);
}
static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
.func = bpf_probe_read_compat_str,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_UNINIT_MEM,
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
u32, size)
{
/*
@ -186,10 +302,8 @@ BPF_CALL_3(bpf_probe_write_user, void *, unsafe_ptr, const void *, src,
return -EPERM;
if (unlikely(!nmi_uaccess_okay()))
return -EPERM;
if (!access_ok(unsafe_ptr, size))
return -EPERM;
return probe_kernel_write(unsafe_ptr, src, size);
return probe_user_write(unsafe_ptr, src, size);
}
static const struct bpf_func_proto bpf_probe_write_user_proto = {
@ -585,41 +699,6 @@ static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = {
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_probe_read_str, void *, dst, u32, size,
const void *, unsafe_ptr)
{
int ret;
ret = security_locked_down(LOCKDOWN_BPF_READ);
if (ret < 0)
goto out;
/*
* The strncpy_from_unsafe() call will likely not fill the entire
* buffer, but that's okay in this circumstance as we're probing
* arbitrary memory anyway similar to bpf_probe_read() and might
* as well probe the stack. Thus, memory is explicitly cleared
* only in error case, so that improper users ignoring return
* code altogether don't copy garbage; otherwise length of string
* is returned that can be used for bpf_perf_event_output() et al.
*/
ret = strncpy_from_unsafe(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
out:
memset(dst, 0, size);
return ret;
}
static const struct bpf_func_proto bpf_probe_read_str_proto = {
.func = bpf_probe_read_str,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_UNINIT_MEM,
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_ANYTHING,
};
struct send_signal_irq_work {
struct irq_work irq_work;
struct task_struct *task;
@ -699,8 +778,6 @@ tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_map_pop_elem_proto;
case BPF_FUNC_map_peek_elem:
return &bpf_map_peek_elem_proto;
case BPF_FUNC_probe_read:
return &bpf_probe_read_proto;
case BPF_FUNC_ktime_get_ns:
return &bpf_ktime_get_ns_proto;
case BPF_FUNC_tail_call:
@ -727,8 +804,18 @@ tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_current_task_under_cgroup_proto;
case BPF_FUNC_get_prandom_u32:
return &bpf_get_prandom_u32_proto;
case BPF_FUNC_probe_read_user:
return &bpf_probe_read_user_proto;
case BPF_FUNC_probe_read_kernel:
return &bpf_probe_read_kernel_proto;
case BPF_FUNC_probe_read:
return &bpf_probe_read_compat_proto;
case BPF_FUNC_probe_read_user_str:
return &bpf_probe_read_user_str_proto;
case BPF_FUNC_probe_read_kernel_str:
return &bpf_probe_read_kernel_str_proto;
case BPF_FUNC_probe_read_str:
return &bpf_probe_read_str_proto;
return &bpf_probe_read_compat_str_proto;
#ifdef CONFIG_CGROUPS
case BPF_FUNC_get_current_cgroup_id:
return &bpf_get_current_cgroup_id_proto;
@ -1055,10 +1142,6 @@ raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
switch (func_id) {
case BPF_FUNC_perf_event_output:
return &bpf_perf_event_output_proto_raw_tp;
#ifdef CONFIG_NET
case BPF_FUNC_skb_output:
return &bpf_skb_output_proto;
#endif
case BPF_FUNC_get_stackid:
return &bpf_get_stackid_proto_raw_tp;
case BPF_FUNC_get_stack:
@ -1068,20 +1151,44 @@ raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
}
}
static const struct bpf_func_proto *
tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
#ifdef CONFIG_NET
case BPF_FUNC_skb_output:
return &bpf_skb_output_proto;
#endif
default:
return raw_tp_prog_func_proto(func_id, prog);
}
}
static bool raw_tp_prog_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
/* largest tracepoint in the kernel has 12 args */
if (off < 0 || off >= sizeof(__u64) * 12)
if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS)
return false;
if (type != BPF_READ)
return false;
if (off % size != 0)
return false;
if (!prog->aux->attach_btf_id)
return true;
}
static bool tracing_prog_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS)
return false;
if (type != BPF_READ)
return false;
if (off % size != 0)
return false;
return btf_ctx_access(off, size, type, prog, info);
}
@ -1093,6 +1200,14 @@ const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
const struct bpf_prog_ops raw_tracepoint_prog_ops = {
};
const struct bpf_verifier_ops tracing_verifier_ops = {
.get_func_proto = tracing_prog_func_proto,
.is_valid_access = tracing_prog_is_valid_access,
};
const struct bpf_prog_ops tracing_prog_ops = {
};
static bool raw_tp_writable_prog_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,

View File

@ -6859,34 +6859,128 @@ static __init struct sk_buff *build_test_skb(void)
return NULL;
}
static __init int test_skb_segment(void)
static __init struct sk_buff *build_test_skb_linear_no_head_frag(void)
{
unsigned int alloc_size = 2000;
unsigned int headroom = 102, doffset = 72, data_size = 1308;
struct sk_buff *skb[2];
int i;
/* skbs linked in a frag_list, both with linear data, with head_frag=0
* (data allocated by kmalloc), both have tcp data of 1308 bytes
* (total payload is 2616 bytes).
* Data offset is 72 bytes (40 ipv6 hdr, 32 tcp hdr). Some headroom.
*/
for (i = 0; i < 2; i++) {
skb[i] = alloc_skb(alloc_size, GFP_KERNEL);
if (!skb[i]) {
if (i == 0)
goto err_skb0;
else
goto err_skb1;
}
skb[i]->protocol = htons(ETH_P_IPV6);
skb_reserve(skb[i], headroom);
skb_put(skb[i], doffset + data_size);
skb_reset_network_header(skb[i]);
if (i == 0)
skb_reset_mac_header(skb[i]);
else
skb_set_mac_header(skb[i], -ETH_HLEN);
__skb_pull(skb[i], doffset);
}
/* setup shinfo.
* mimic bpf_skb_proto_4_to_6, which resets gso_segs and assigns a
* reduced gso_size.
*/
skb_shinfo(skb[0])->gso_size = 1288;
skb_shinfo(skb[0])->gso_type = SKB_GSO_TCPV6 | SKB_GSO_DODGY;
skb_shinfo(skb[0])->gso_segs = 0;
skb_shinfo(skb[0])->frag_list = skb[1];
/* adjust skb[0]'s len */
skb[0]->len += skb[1]->len;
skb[0]->data_len += skb[1]->len;
skb[0]->truesize += skb[1]->truesize;
return skb[0];
err_skb1:
kfree_skb(skb[0]);
err_skb0:
return NULL;
}
struct skb_segment_test {
const char *descr;
struct sk_buff *(*build_skb)(void);
netdev_features_t features;
};
static struct skb_segment_test skb_segment_tests[] __initconst = {
{
.descr = "gso_with_rx_frags",
.build_skb = build_test_skb,
.features = NETIF_F_SG | NETIF_F_GSO_PARTIAL | NETIF_F_IP_CSUM |
NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM
},
{
.descr = "gso_linear_no_head_frag",
.build_skb = build_test_skb_linear_no_head_frag,
.features = NETIF_F_SG | NETIF_F_FRAGLIST |
NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_GSO |
NETIF_F_LLTX_BIT | NETIF_F_GRO |
NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM |
NETIF_F_HW_VLAN_STAG_TX_BIT
}
};
static __init int test_skb_segment_single(const struct skb_segment_test *test)
{
struct sk_buff *skb, *segs;
int ret = -1;
features = NETIF_F_SG | NETIF_F_GSO_PARTIAL | NETIF_F_IP_CSUM |
NETIF_F_IPV6_CSUM;
features |= NETIF_F_RXCSUM;
skb = build_test_skb();
skb = test->build_skb();
if (!skb) {
pr_info("%s: failed to build_test_skb", __func__);
goto done;
}
segs = skb_segment(skb, features);
segs = skb_segment(skb, test->features);
if (!IS_ERR(segs)) {
kfree_skb_list(segs);
ret = 0;
pr_info("%s: success in skb_segment!", __func__);
} else {
pr_info("%s: failed in skb_segment!", __func__);
}
kfree_skb(skb);
done:
return ret;
}
static __init int test_skb_segment(void)
{
int i, err_cnt = 0, pass_cnt = 0;
for (i = 0; i < ARRAY_SIZE(skb_segment_tests); i++) {
const struct skb_segment_test *test = &skb_segment_tests[i];
pr_info("#%d %s ", i, test->descr);
if (test_skb_segment_single(test)) {
pr_cont("FAIL\n");
err_cnt++;
} else {
pr_cont("PASS\n");
pass_cnt++;
}
}
pr_info("%s: Summary: %d PASSED, %d FAILED\n", __func__,
pass_cnt, err_cnt);
return err_cnt ? -EINVAL : 0;
}
static __init int test_bpf(void)
{
int i, err_cnt = 0, pass_cnt = 0;

View File

@ -18,6 +18,18 @@ probe_read_common(void *dst, const void __user *src, size_t size)
return ret ? -EFAULT : 0;
}
static __always_inline long
probe_write_common(void __user *dst, const void *src, size_t size)
{
long ret;
pagefault_disable();
ret = __copy_to_user_inatomic(dst, src, size);
pagefault_enable();
return ret ? -EFAULT : 0;
}
/**
* probe_kernel_read(): safely attempt to read from a kernel-space location
* @dst: pointer to the buffer that shall take the data
@ -31,11 +43,20 @@ probe_read_common(void *dst, const void __user *src, size_t size)
* do_page_fault() doesn't attempt to take mmap_sem. This makes
* probe_kernel_read() suitable for use within regions where the caller
* already holds mmap_sem, or other locks which nest inside mmap_sem.
*
* probe_kernel_read_strict() is the same as probe_kernel_read() except for
* the case where architectures have non-overlapping user and kernel address
* ranges: probe_kernel_read_strict() will additionally return -EFAULT for
* probing memory on a user address range where probe_user_read() is supposed
* to be used instead.
*/
long __weak probe_kernel_read(void *dst, const void *src, size_t size)
__attribute__((alias("__probe_kernel_read")));
long __weak probe_kernel_read_strict(void *dst, const void *src, size_t size)
__attribute__((alias("__probe_kernel_read")));
long __probe_kernel_read(void *dst, const void *src, size_t size)
{
long ret;
@ -85,6 +106,7 @@ EXPORT_SYMBOL_GPL(probe_user_read);
* Safely write to address @dst from the buffer at @src. If a kernel fault
* happens, handle that and return -EFAULT.
*/
long __weak probe_kernel_write(void *dst, const void *src, size_t size)
__attribute__((alias("__probe_kernel_write")));
@ -94,15 +116,39 @@ long __probe_kernel_write(void *dst, const void *src, size_t size)
mm_segment_t old_fs = get_fs();
set_fs(KERNEL_DS);
pagefault_disable();
ret = __copy_to_user_inatomic((__force void __user *)dst, src, size);
pagefault_enable();
ret = probe_write_common((__force void __user *)dst, src, size);
set_fs(old_fs);
return ret ? -EFAULT : 0;
return ret;
}
EXPORT_SYMBOL_GPL(probe_kernel_write);
/**
* probe_user_write(): safely attempt to write to a user-space location
* @dst: address to write to
* @src: pointer to the data that shall be written
* @size: size of the data chunk
*
* Safely write to address @dst from the buffer at @src. If a kernel fault
* happens, handle that and return -EFAULT.
*/
long __weak probe_user_write(void __user *dst, const void *src, size_t size)
__attribute__((alias("__probe_user_write")));
long __probe_user_write(void __user *dst, const void *src, size_t size)
{
long ret = -EFAULT;
mm_segment_t old_fs = get_fs();
set_fs(USER_DS);
if (access_ok(dst, size))
ret = probe_write_common(dst, src, size);
set_fs(old_fs);
return ret;
}
EXPORT_SYMBOL_GPL(probe_user_write);
/**
* strncpy_from_unsafe: - Copy a NUL terminated string from unsafe address.
@ -120,8 +166,22 @@ EXPORT_SYMBOL_GPL(probe_kernel_write);
*
* If @count is smaller than the length of the string, copies @count-1 bytes,
* sets the last byte of @dst buffer to NUL and returns @count.
*
* strncpy_from_unsafe_strict() is the same as strncpy_from_unsafe() except
* for the case where architectures have non-overlapping user and kernel address
* ranges: strncpy_from_unsafe_strict() will additionally return -EFAULT for
* probing memory on a user address range where strncpy_from_unsafe_user() is
* supposed to be used instead.
*/
long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count)
long __weak strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count)
__attribute__((alias("__strncpy_from_unsafe")));
long __weak strncpy_from_unsafe_strict(char *dst, const void *unsafe_addr,
long count)
__attribute__((alias("__strncpy_from_unsafe")));
long __strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count)
{
mm_segment_t old_fs = get_fs();
const void *src = unsafe_addr;

View File

@ -196,7 +196,7 @@ static bool xsk_is_bound(struct xdp_sock *xs)
return false;
}
int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
static int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
{
u32 len;
@ -212,7 +212,7 @@ int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
__xsk_rcv_zc(xs, xdp, len) : __xsk_rcv(xs, xdp, len);
}
void xsk_flush(struct xdp_sock *xs)
static void xsk_flush(struct xdp_sock *xs)
{
xskq_produce_flush_desc(xs->rx);
xs->sk.sk_data_ready(&xs->sk);
@ -264,6 +264,35 @@ int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
return err;
}
int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp,
struct xdp_sock *xs)
{
struct xsk_map *m = container_of(map, struct xsk_map, map);
struct list_head *flush_list = this_cpu_ptr(m->flush_list);
int err;
err = xsk_rcv(xs, xdp);
if (err)
return err;
if (!xs->flush_node.prev)
list_add(&xs->flush_node, flush_list);
return 0;
}
void __xsk_map_flush(struct bpf_map *map)
{
struct xsk_map *m = container_of(map, struct xsk_map, map);
struct list_head *flush_list = this_cpu_ptr(m->flush_list);
struct xdp_sock *xs, *tmp;
list_for_each_entry_safe(xs, tmp, flush_list, flush_node) {
xsk_flush(xs);
__list_del_clearprev(&xs->flush_node);
}
}
void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries)
{
xskq_produce_flush_addr_n(umem->cq, nb_entries);

View File

@ -181,7 +181,7 @@ int stress_lru_hmap_alloc(struct pt_regs *ctx)
if (addrlen != sizeof(*in6))
return 0;
ret = bpf_probe_read(test_params.dst6, sizeof(test_params.dst6),
ret = bpf_probe_read_user(test_params.dst6, sizeof(test_params.dst6),
&in6->sin6_addr);
if (ret)
goto done;

View File

@ -118,7 +118,7 @@ int trace_sys_connect(struct pt_regs *ctx)
if (addrlen != sizeof(*in6))
return 0;
ret = bpf_probe_read(dst6, sizeof(dst6), &in6->sin6_addr);
ret = bpf_probe_read_user(dst6, sizeof(dst6), &in6->sin6_addr);
if (ret) {
inline_ret = ret;
goto done;
@ -129,7 +129,7 @@ int trace_sys_connect(struct pt_regs *ctx)
test_case = dst6[7];
ret = bpf_probe_read(&port, sizeof(port), &in6->sin6_port);
ret = bpf_probe_read_user(&port, sizeof(port), &in6->sin6_port);
if (ret) {
inline_ret = ret;
goto done;

View File

@ -37,7 +37,7 @@ int bpf_prog1(struct pt_regs *ctx)
if (sockaddr_len > sizeof(orig_addr))
return 0;
if (bpf_probe_read(&orig_addr, sizeof(orig_addr), sockaddr_arg) != 0)
if (bpf_probe_read_user(&orig_addr, sizeof(orig_addr), sockaddr_arg) != 0)
return 0;
mapped_addr = bpf_map_lookup_elem(&dnat_map, &orig_addr);

View File

@ -173,6 +173,7 @@ enum bpf_prog_type {
BPF_PROG_TYPE_CGROUP_SYSCTL,
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
BPF_PROG_TYPE_CGROUP_SOCKOPT,
BPF_PROG_TYPE_TRACING,
};
enum bpf_attach_type {
@ -199,6 +200,7 @@ enum bpf_attach_type {
BPF_CGROUP_UDP6_RECVMSG,
BPF_CGROUP_GETSOCKOPT,
BPF_CGROUP_SETSOCKOPT,
BPF_TRACE_RAW_TP,
__MAX_BPF_ATTACH_TYPE
};
@ -561,10 +563,13 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read(void *dst, u32 size, const void *src)
* int bpf_probe_read(void *dst, u32 size, const void *unsafe_ptr)
* Description
* For tracing programs, safely attempt to read *size* bytes from
* address *src* and store the data in *dst*.
* kernel space address *unsafe_ptr* and store the data in *dst*.
*
* Generally, use bpf_probe_read_user() or bpf_probe_read_kernel()
* instead.
* Return
* 0 on success, or a negative error in case of failure.
*
@ -1426,45 +1431,14 @@ union bpf_attr {
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
* int bpf_probe_read_str(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Copy a NUL terminated string from an unsafe address
* *unsafe_ptr* to *dst*. The *size* should include the
* terminating NUL byte. In case the string length is smaller than
* *size*, the target is not padded with further NUL bytes. If the
* string length is larger than *size*, just *size*-1 bytes are
* copied and the last byte is set to NUL.
* Copy a NUL terminated string from an unsafe kernel address
* *unsafe_ptr* to *dst*. See bpf_probe_read_kernel_str() for
* more details.
*
* On success, the length of the copied string is returned. This
* makes this helper useful in tracing programs for reading
* strings, and more importantly to get its length at runtime. See
* the following snippet:
*
* ::
*
* SEC("kprobe/sys_open")
* void bpf_sys_open(struct pt_regs *ctx)
* {
* char buf[PATHLEN]; // PATHLEN is defined to 256
* int res = bpf_probe_read_str(buf, sizeof(buf),
* ctx->di);
*
* // Consume buf, for example push it to
* // userspace via bpf_perf_event_output(); we
* // can use res (the string length) as event
* // size, after checking its boundaries.
* }
*
* In comparison, using **bpf_probe_read()** helper here instead
* to read the string would require to estimate the length at
* compile time, and would often result in copying more memory
* than necessary.
*
* Another useful use case is when parsing individual process
* arguments or individual environment variables navigating
* *current*\ **->mm->arg_start** and *current*\
* **->mm->env_start**: using this helper and the return value,
* one can quickly iterate at the right offset of the memory area.
* Generally, use bpf_probe_read_user_str() or bpf_probe_read_kernel_str()
* instead.
* Return
* On success, the strictly positive length of the string,
* including the trailing NUL character. On error, a negative
@ -2775,6 +2749,72 @@ union bpf_attr {
* restricted to raw_tracepoint bpf programs.
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read_user(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Safely attempt to read *size* bytes from user space address
* *unsafe_ptr* and store the data in *dst*.
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Safely attempt to read *size* bytes from kernel space address
* *unsafe_ptr* and store the data in *dst*.
* Return
* 0 on success, or a negative error in case of failure.
*
* int bpf_probe_read_user_str(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Copy a NUL terminated string from an unsafe user address
* *unsafe_ptr* to *dst*. The *size* should include the
* terminating NUL byte. In case the string length is smaller than
* *size*, the target is not padded with further NUL bytes. If the
* string length is larger than *size*, just *size*-1 bytes are
* copied and the last byte is set to NUL.
*
* On success, the length of the copied string is returned. This
* makes this helper useful in tracing programs for reading
* strings, and more importantly to get its length at runtime. See
* the following snippet:
*
* ::
*
* SEC("kprobe/sys_open")
* void bpf_sys_open(struct pt_regs *ctx)
* {
* char buf[PATHLEN]; // PATHLEN is defined to 256
* int res = bpf_probe_read_user_str(buf, sizeof(buf),
* ctx->di);
*
* // Consume buf, for example push it to
* // userspace via bpf_perf_event_output(); we
* // can use res (the string length) as event
* // size, after checking its boundaries.
* }
*
* In comparison, using **bpf_probe_read_user()** helper here
* instead to read the string would require to estimate the length
* at compile time, and would often result in copying more memory
* than necessary.
*
* Another useful use case is when parsing individual process
* arguments or individual environment variables navigating
* *current*\ **->mm->arg_start** and *current*\
* **->mm->env_start**: using this helper and the return value,
* one can quickly iterate at the right offset of the memory area.
* Return
* On success, the strictly positive length of the string,
* including the trailing NUL character. On error, a negative
* value.
*
* int bpf_probe_read_kernel_str(void *dst, u32 size, const void *unsafe_ptr)
* Description
* Copy a NUL terminated string from an unsafe kernel address *unsafe_ptr*
* to *dst*. Same semantics as with bpf_probe_read_user_str() apply.
* Return
* On success, the strictly positive length of the string, including
* the trailing NUL character. On error, a negative value.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@ -2888,7 +2928,11 @@ union bpf_attr {
FN(sk_storage_delete), \
FN(send_signal), \
FN(tcp_gen_syncookie), \
FN(skb_output),
FN(skb_output), \
FN(probe_read_user), \
FN(probe_read_kernel), \
FN(probe_read_user_str), \
FN(probe_read_kernel_str),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call

View File

@ -228,9 +228,10 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
memset(&attr, 0, sizeof(attr));
attr.prog_type = load_attr->prog_type;
attr.expected_attach_type = load_attr->expected_attach_type;
if (attr.prog_type == BPF_PROG_TYPE_RAW_TRACEPOINT)
/* expected_attach_type is ignored for tracing progs */
attr.attach_btf_id = attr.expected_attach_type;
if (attr.prog_type == BPF_PROG_TYPE_TRACING)
attr.attach_btf_id = load_attr->attach_btf_id;
else
attr.prog_ifindex = load_attr->prog_ifindex;
attr.insn_cnt = (__u32)load_attr->insns_cnt;
attr.insns = ptr_to_u64(load_attr->insns);
attr.license = ptr_to_u64(load_attr->license);
@ -245,7 +246,6 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
}
attr.kern_version = load_attr->kern_version;
attr.prog_ifindex = load_attr->prog_ifindex;
attr.prog_btf_fd = load_attr->prog_btf_fd;
attr.func_info_rec_size = load_attr->func_info_rec_size;
attr.func_info_cnt = load_attr->func_info_cnt;

View File

@ -78,7 +78,10 @@ struct bpf_load_program_attr {
size_t insns_cnt;
const char *license;
__u32 kern_version;
union {
__u32 prog_ifindex;
__u32 attach_btf_id;
};
__u32 prog_btf_fd;
__u32 func_info_rec_size;
const void *func_info;

View File

@ -38,4 +38,10 @@ struct bpf_map_def {
unsigned int map_flags;
};
enum libbpf_pin_type {
LIBBPF_PIN_NONE,
/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
LIBBPF_PIN_BY_NAME,
};
#endif

View File

@ -188,6 +188,7 @@ struct bpf_program {
bpf_program_clear_priv_t clear_priv;
enum bpf_attach_type expected_attach_type;
__u32 attach_btf_id;
void *func_info;
__u32 func_info_rec_size;
__u32 func_info_cnt;
@ -226,6 +227,8 @@ struct bpf_map {
void *priv;
bpf_map_clear_priv_t clear_priv;
enum libbpf_map_type libbpf_type;
char *pin_path;
bool pinned;
};
struct bpf_secdata {
@ -1090,10 +1093,32 @@ static bool get_map_field_int(const char *map_name, const struct btf *btf,
return true;
}
static int build_map_pin_path(struct bpf_map *map, const char *path)
{
char buf[PATH_MAX];
int err, len;
if (!path)
path = "/sys/fs/bpf";
len = snprintf(buf, PATH_MAX, "%s/%s", path, bpf_map__name(map));
if (len < 0)
return -EINVAL;
else if (len >= PATH_MAX)
return -ENAMETOOLONG;
err = bpf_map__set_pin_path(map, buf);
if (err)
return err;
return 0;
}
static int bpf_object__init_user_btf_map(struct bpf_object *obj,
const struct btf_type *sec,
int var_idx, int sec_idx,
const Elf_Data *data, bool strict)
const Elf_Data *data, bool strict,
const char *pin_root_path)
{
const struct btf_type *var, *def, *t;
const struct btf_var_secinfo *vi;
@ -1268,6 +1293,30 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
}
map->def.value_size = sz;
map->btf_value_type_id = t->type;
} else if (strcmp(name, "pinning") == 0) {
__u32 val;
int err;
if (!get_map_field_int(map_name, obj->btf, def, m,
&val))
return -EINVAL;
pr_debug("map '%s': found pinning = %u.\n",
map_name, val);
if (val != LIBBPF_PIN_NONE &&
val != LIBBPF_PIN_BY_NAME) {
pr_warn("map '%s': invalid pinning value %u.\n",
map_name, val);
return -EINVAL;
}
if (val == LIBBPF_PIN_BY_NAME) {
err = build_map_pin_path(map, pin_root_path);
if (err) {
pr_warn("map '%s': couldn't build pin path.\n",
map_name);
return err;
}
}
} else {
if (strict) {
pr_warn("map '%s': unknown field '%s'.\n",
@ -1287,7 +1336,8 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
return 0;
}
static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict)
static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict,
const char *pin_root_path)
{
const struct btf_type *sec = NULL;
int nr_types, i, vlen, err;
@ -1329,7 +1379,7 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict)
for (i = 0; i < vlen; i++) {
err = bpf_object__init_user_btf_map(obj, sec, i,
obj->efile.btf_maps_shndx,
data, strict);
data, strict, pin_root_path);
if (err)
return err;
}
@ -1337,7 +1387,8 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict)
return 0;
}
static int bpf_object__init_maps(struct bpf_object *obj, bool relaxed_maps)
static int bpf_object__init_maps(struct bpf_object *obj, bool relaxed_maps,
const char *pin_root_path)
{
bool strict = !relaxed_maps;
int err;
@ -1346,7 +1397,7 @@ static int bpf_object__init_maps(struct bpf_object *obj, bool relaxed_maps)
if (err)
return err;
err = bpf_object__init_user_btf_maps(obj, strict);
err = bpf_object__init_user_btf_maps(obj, strict, pin_root_path);
if (err)
return err;
@ -1535,7 +1586,8 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj)
return 0;
}
static int bpf_object__elf_collect(struct bpf_object *obj, bool relaxed_maps)
static int bpf_object__elf_collect(struct bpf_object *obj, bool relaxed_maps,
const char *pin_root_path)
{
Elf *elf = obj->efile.elf;
GElf_Ehdr *ep = &obj->efile.ehdr;
@ -1664,13 +1716,13 @@ static int bpf_object__elf_collect(struct bpf_object *obj, bool relaxed_maps)
}
}
if (!obj->efile.strtabidx || obj->efile.strtabidx >= idx) {
if (!obj->efile.strtabidx || obj->efile.strtabidx > idx) {
pr_warn("Corrupted ELF file: index of strtab invalid\n");
return -LIBBPF_ERRNO__FORMAT;
}
err = bpf_object__init_btf(obj, btf_data, btf_ext_data);
if (!err)
err = bpf_object__init_maps(obj, relaxed_maps);
err = bpf_object__init_maps(obj, relaxed_maps, pin_root_path);
if (!err)
err = bpf_object__sanitize_and_load_btf(obj);
if (!err)
@ -1916,16 +1968,22 @@ int bpf_map__reuse_fd(struct bpf_map *map, int fd)
return -errno;
new_fd = open("/", O_RDONLY | O_CLOEXEC);
if (new_fd < 0)
if (new_fd < 0) {
err = -errno;
goto err_free_new_name;
}
new_fd = dup3(fd, new_fd, O_CLOEXEC);
if (new_fd < 0)
if (new_fd < 0) {
err = -errno;
goto err_close_new_fd;
}
err = zclose(map->fd);
if (err)
if (err) {
err = -errno;
goto err_close_new_fd;
}
free(map->name);
map->fd = new_fd;
@ -1944,7 +2002,7 @@ int bpf_map__reuse_fd(struct bpf_map *map, int fd)
close(new_fd);
err_free_new_name:
free(new_name);
return -errno;
return err;
}
int bpf_map__resize(struct bpf_map *map, __u32 max_entries)
@ -2120,6 +2178,66 @@ bpf_object__probe_caps(struct bpf_object *obj)
return 0;
}
static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd)
{
struct bpf_map_info map_info = {};
char msg[STRERR_BUFSIZE];
__u32 map_info_len;
map_info_len = sizeof(map_info);
if (bpf_obj_get_info_by_fd(map_fd, &map_info, &map_info_len)) {
pr_warn("failed to get map info for map FD %d: %s\n",
map_fd, libbpf_strerror_r(errno, msg, sizeof(msg)));
return false;
}
return (map_info.type == map->def.type &&
map_info.key_size == map->def.key_size &&
map_info.value_size == map->def.value_size &&
map_info.max_entries == map->def.max_entries &&
map_info.map_flags == map->def.map_flags);
}
static int
bpf_object__reuse_map(struct bpf_map *map)
{
char *cp, errmsg[STRERR_BUFSIZE];
int err, pin_fd;
pin_fd = bpf_obj_get(map->pin_path);
if (pin_fd < 0) {
err = -errno;
if (err == -ENOENT) {
pr_debug("found no pinned map to reuse at '%s'\n",
map->pin_path);
return 0;
}
cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg));
pr_warn("couldn't retrieve pinned map '%s': %s\n",
map->pin_path, cp);
return err;
}
if (!map_is_reuse_compat(map, pin_fd)) {
pr_warn("couldn't reuse pinned map at '%s': parameter mismatch\n",
map->pin_path);
close(pin_fd);
return -EINVAL;
}
err = bpf_map__reuse_fd(map, pin_fd);
if (err) {
close(pin_fd);
return err;
}
map->pinned = true;
pr_debug("reused pinned map at '%s'\n", map->pin_path);
return 0;
}
static int
bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map)
{
@ -2162,6 +2280,15 @@ bpf_object__create_maps(struct bpf_object *obj)
char *cp, errmsg[STRERR_BUFSIZE];
int *pfd = &map->fd;
if (map->pin_path) {
err = bpf_object__reuse_map(map);
if (err) {
pr_warn("error reusing pinned map %s\n",
map->name);
return err;
}
}
if (map->fd >= 0) {
pr_debug("skip map create (preset) %s: fd=%d\n",
map->name, map->fd);
@ -2240,6 +2367,15 @@ bpf_object__create_maps(struct bpf_object *obj)
}
}
if (map->pin_path && !map->pinned) {
err = bpf_map__pin(map, NULL);
if (err) {
pr_warn("failed to auto-pin map name '%s' at '%s'\n",
map->name, map->pin_path);
return err;
}
}
pr_debug("created map %s: fd=%d\n", map->name, *pfd);
}
@ -3446,6 +3582,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
load_attr.line_info_cnt = prog->line_info_cnt;
load_attr.log_level = prog->log_level;
load_attr.prog_flags = prog->prog_flags;
load_attr.attach_btf_id = prog->attach_btf_id;
retry_load:
log_buf = malloc(log_buf_size);
@ -3607,10 +3744,13 @@ bpf_object__load_progs(struct bpf_object *obj, int log_level)
return 0;
}
static int libbpf_attach_btf_id_by_name(const char *name, __u32 *btf_id);
static struct bpf_object *
__bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
struct bpf_object_open_opts *opts)
{
const char *pin_root_path;
struct bpf_program *prog;
struct bpf_object *obj;
const char *obj_name;
@ -3645,17 +3785,20 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
obj->relaxed_core_relocs = OPTS_GET(opts, relaxed_core_relocs, false);
relaxed_maps = OPTS_GET(opts, relaxed_maps, false);
pin_root_path = OPTS_GET(opts, pin_root_path, NULL);
CHECK_ERR(bpf_object__elf_init(obj), err, out);
CHECK_ERR(bpf_object__check_endianness(obj), err, out);
CHECK_ERR(bpf_object__probe_caps(obj), err, out);
CHECK_ERR(bpf_object__elf_collect(obj, relaxed_maps), err, out);
CHECK_ERR(bpf_object__elf_collect(obj, relaxed_maps, pin_root_path),
err, out);
CHECK_ERR(bpf_object__collect_reloc(obj), err, out);
bpf_object__elf_finish(obj);
bpf_object__for_each_program(prog, obj) {
enum bpf_prog_type prog_type;
enum bpf_attach_type attach_type;
__u32 btf_id;
err = libbpf_prog_type_by_name(prog->section_name, &prog_type,
&attach_type);
@ -3667,6 +3810,12 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
bpf_program__set_type(prog, prog_type);
bpf_program__set_expected_attach_type(prog, attach_type);
if (prog_type == BPF_PROG_TYPE_TRACING) {
err = libbpf_attach_btf_id_by_name(prog->section_name, &btf_id);
if (err)
goto out;
prog->attach_btf_id = btf_id;
}
}
return obj;
@ -3797,6 +3946,28 @@ int bpf_object__load(struct bpf_object *obj)
return bpf_object__load_xattr(&attr);
}
static int make_parent_dir(const char *path)
{
char *cp, errmsg[STRERR_BUFSIZE];
char *dname, *dir;
int err = 0;
dname = strdup(path);
if (dname == NULL)
return -ENOMEM;
dir = dirname(dname);
if (mkdir(dir, 0700) && errno != EEXIST)
err = -errno;
free(dname);
if (err) {
cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg));
pr_warn("failed to mkdir %s: %s\n", path, cp);
}
return err;
}
static int check_path(const char *path)
{
char *cp, errmsg[STRERR_BUFSIZE];
@ -3833,6 +4004,10 @@ int bpf_program__pin_instance(struct bpf_program *prog, const char *path,
char *cp, errmsg[STRERR_BUFSIZE];
int err;
err = make_parent_dir(path);
if (err)
return err;
err = check_path(path);
if (err)
return err;
@ -3886,25 +4061,14 @@ int bpf_program__unpin_instance(struct bpf_program *prog, const char *path,
return 0;
}
static int make_dir(const char *path)
{
char *cp, errmsg[STRERR_BUFSIZE];
int err = 0;
if (mkdir(path, 0700) && errno != EEXIST)
err = -errno;
if (err) {
cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg));
pr_warn("failed to mkdir %s: %s\n", path, cp);
}
return err;
}
int bpf_program__pin(struct bpf_program *prog, const char *path)
{
int i, err;
err = make_parent_dir(path);
if (err)
return err;
err = check_path(path);
if (err)
return err;
@ -3925,10 +4089,6 @@ int bpf_program__pin(struct bpf_program *prog, const char *path)
return bpf_program__pin_instance(prog, path, 0);
}
err = make_dir(path);
if (err)
return err;
for (i = 0; i < prog->instances.nr; i++) {
char buf[PATH_MAX];
int len;
@ -4019,47 +4179,123 @@ int bpf_map__pin(struct bpf_map *map, const char *path)
char *cp, errmsg[STRERR_BUFSIZE];
int err;
err = check_path(path);
if (err)
return err;
if (map == NULL) {
pr_warn("invalid map pointer\n");
return -EINVAL;
}
if (bpf_obj_pin(map->fd, path)) {
cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
pr_warn("failed to pin map: %s\n", cp);
return -errno;
if (map->pin_path) {
if (path && strcmp(path, map->pin_path)) {
pr_warn("map '%s' already has pin path '%s' different from '%s'\n",
bpf_map__name(map), map->pin_path, path);
return -EINVAL;
} else if (map->pinned) {
pr_debug("map '%s' already pinned at '%s'; not re-pinning\n",
bpf_map__name(map), map->pin_path);
return 0;
}
} else {
if (!path) {
pr_warn("missing a path to pin map '%s' at\n",
bpf_map__name(map));
return -EINVAL;
} else if (map->pinned) {
pr_warn("map '%s' already pinned\n", bpf_map__name(map));
return -EEXIST;
}
pr_debug("pinned map '%s'\n", path);
map->pin_path = strdup(path);
if (!map->pin_path) {
err = -errno;
goto out_err;
}
}
err = make_parent_dir(map->pin_path);
if (err)
return err;
err = check_path(map->pin_path);
if (err)
return err;
if (bpf_obj_pin(map->fd, map->pin_path)) {
err = -errno;
goto out_err;
}
map->pinned = true;
pr_debug("pinned map '%s'\n", map->pin_path);
return 0;
out_err:
cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg));
pr_warn("failed to pin map: %s\n", cp);
return err;
}
int bpf_map__unpin(struct bpf_map *map, const char *path)
{
int err;
err = check_path(path);
if (err)
return err;
if (map == NULL) {
pr_warn("invalid map pointer\n");
return -EINVAL;
}
if (map->pin_path) {
if (path && strcmp(path, map->pin_path)) {
pr_warn("map '%s' already has pin path '%s' different from '%s'\n",
bpf_map__name(map), map->pin_path, path);
return -EINVAL;
}
path = map->pin_path;
} else if (!path) {
pr_warn("no path to unpin map '%s' from\n",
bpf_map__name(map));
return -EINVAL;
}
err = check_path(path);
if (err)
return err;
err = unlink(path);
if (err != 0)
return -errno;
pr_debug("unpinned map '%s'\n", path);
map->pinned = false;
pr_debug("unpinned map '%s' from '%s'\n", bpf_map__name(map), path);
return 0;
}
int bpf_map__set_pin_path(struct bpf_map *map, const char *path)
{
char *new = NULL;
if (path) {
new = strdup(path);
if (!new)
return -errno;
}
free(map->pin_path);
map->pin_path = new;
return 0;
}
const char *bpf_map__get_pin_path(const struct bpf_map *map)
{
return map->pin_path;
}
bool bpf_map__is_pinned(const struct bpf_map *map)
{
return map->pinned;
}
int bpf_object__pin_maps(struct bpf_object *obj, const char *path)
{
struct bpf_map *map;
@ -4073,12 +4309,11 @@ int bpf_object__pin_maps(struct bpf_object *obj, const char *path)
return -ENOENT;
}
err = make_dir(path);
if (err)
return err;
bpf_object__for_each_map(map, obj) {
char *pin_path = NULL;
char buf[PATH_MAX];
if (path) {
int len;
len = snprintf(buf, PATH_MAX, "%s/%s", path,
@ -4090,8 +4325,12 @@ int bpf_object__pin_maps(struct bpf_object *obj, const char *path)
err = -ENAMETOOLONG;
goto err_unpin_maps;
}
pin_path = buf;
} else if (!map->pin_path) {
continue;
}
err = bpf_map__pin(map, buf);
err = bpf_map__pin(map, pin_path);
if (err)
goto err_unpin_maps;
}
@ -4100,17 +4339,10 @@ int bpf_object__pin_maps(struct bpf_object *obj, const char *path)
err_unpin_maps:
while ((map = bpf_map__prev(map, obj))) {
char buf[PATH_MAX];
int len;
len = snprintf(buf, PATH_MAX, "%s/%s", path,
bpf_map__name(map));
if (len < 0)
continue;
else if (len >= PATH_MAX)
if (!map->pin_path)
continue;
bpf_map__unpin(map, buf);
bpf_map__unpin(map, NULL);
}
return err;
@ -4125,7 +4357,10 @@ int bpf_object__unpin_maps(struct bpf_object *obj, const char *path)
return -ENOENT;
bpf_object__for_each_map(map, obj) {
char *pin_path = NULL;
char buf[PATH_MAX];
if (path) {
int len;
len = snprintf(buf, PATH_MAX, "%s/%s", path,
@ -4134,8 +4369,12 @@ int bpf_object__unpin_maps(struct bpf_object *obj, const char *path)
return -EINVAL;
else if (len >= PATH_MAX)
return -ENAMETOOLONG;
pin_path = buf;
} else if (!map->pin_path) {
continue;
}
err = bpf_map__unpin(map, buf);
err = bpf_map__unpin(map, pin_path);
if (err)
return err;
}
@ -4156,10 +4395,6 @@ int bpf_object__pin_programs(struct bpf_object *obj, const char *path)
return -ENOENT;
}
err = make_dir(path);
if (err)
return err;
bpf_object__for_each_program(prog, obj) {
char buf[PATH_MAX];
int len;
@ -4260,6 +4495,7 @@ void bpf_object__close(struct bpf_object *obj)
for (i = 0; i < obj->nr_maps; i++) {
zfree(&obj->maps[i].name);
zfree(&obj->maps[i].pin_path);
if (obj->maps[i].clear_priv)
obj->maps[i].clear_priv(&obj->maps[i],
obj->maps[i].priv);
@ -4518,6 +4754,7 @@ BPF_PROG_TYPE_FNS(tracepoint, BPF_PROG_TYPE_TRACEPOINT);
BPF_PROG_TYPE_FNS(raw_tracepoint, BPF_PROG_TYPE_RAW_TRACEPOINT);
BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP);
BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT);
BPF_PROG_TYPE_FNS(tracing, BPF_PROG_TYPE_TRACING);
enum bpf_attach_type
bpf_program__get_expected_attach_type(struct bpf_program *prog)
@ -4546,7 +4783,8 @@ void bpf_program__set_expected_attach_type(struct bpf_program *prog,
BPF_PROG_SEC_IMPL(string, ptype, eatype, 1, 0, eatype)
/* Programs that use BTF to identify attach point */
#define BPF_PROG_BTF(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, 0, 1, 0)
#define BPF_PROG_BTF(string, ptype, eatype) \
BPF_PROG_SEC_IMPL(string, ptype, eatype, 0, 1, 0)
/* Programs that can be attached but attach type can't be identified by section
* name. Kept for backward compatibility.
@ -4573,7 +4811,8 @@ static const struct {
BPF_PROG_SEC("tp/", BPF_PROG_TYPE_TRACEPOINT),
BPF_PROG_SEC("raw_tracepoint/", BPF_PROG_TYPE_RAW_TRACEPOINT),
BPF_PROG_SEC("raw_tp/", BPF_PROG_TYPE_RAW_TRACEPOINT),
BPF_PROG_BTF("tp_btf/", BPF_PROG_TYPE_RAW_TRACEPOINT),
BPF_PROG_BTF("tp_btf/", BPF_PROG_TYPE_TRACING,
BPF_TRACE_RAW_TP),
BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP),
BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT),
BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN),
@ -4678,27 +4917,6 @@ int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
continue;
*prog_type = section_names[i].prog_type;
*expected_attach_type = section_names[i].expected_attach_type;
if (section_names[i].is_attach_btf) {
struct btf *btf = bpf_core_find_kernel_btf();
char raw_tp_btf_name[128] = "btf_trace_";
char *dst = raw_tp_btf_name + sizeof("btf_trace_") - 1;
int ret;
if (IS_ERR(btf)) {
pr_warn("vmlinux BTF is not found\n");
return -EINVAL;
}
/* prepend "btf_trace_" prefix per kernel convention */
strncat(dst, name + section_names[i].len,
sizeof(raw_tp_btf_name) - sizeof("btf_trace_"));
ret = btf__find_by_name(btf, raw_tp_btf_name);
btf__free(btf);
if (ret <= 0) {
pr_warn("%s is not found in vmlinux BTF\n", dst);
return -EINVAL;
}
*expected_attach_type = ret;
}
return 0;
}
pr_warn("failed to guess program type based on ELF section name '%s'\n", name);
@ -4711,6 +4929,46 @@ int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
return -ESRCH;
}
#define BTF_PREFIX "btf_trace_"
static int libbpf_attach_btf_id_by_name(const char *name, __u32 *btf_id)
{
struct btf *btf = bpf_core_find_kernel_btf();
char raw_tp_btf_name[128] = BTF_PREFIX;
char *dst = raw_tp_btf_name + sizeof(BTF_PREFIX) - 1;
int ret, i, err = -EINVAL;
if (IS_ERR(btf)) {
pr_warn("vmlinux BTF is not found\n");
return -EINVAL;
}
if (!name)
goto out;
for (i = 0; i < ARRAY_SIZE(section_names); i++) {
if (!section_names[i].is_attach_btf)
continue;
if (strncmp(name, section_names[i].sec, section_names[i].len))
continue;
/* prepend "btf_trace_" prefix per kernel convention */
strncat(dst, name + section_names[i].len,
sizeof(raw_tp_btf_name) - sizeof(BTF_PREFIX));
ret = btf__find_by_name(btf, raw_tp_btf_name);
if (ret <= 0) {
pr_warn("%s is not found in vmlinux BTF\n", dst);
goto out;
}
*btf_id = ret;
err = 0;
goto out;
}
pr_warn("failed to identify btf_id based on ELF section name '%s'\n", name);
err = -ESRCH;
out:
btf__free(btf);
return err;
}
int libbpf_attach_type_by_name(const char *name,
enum bpf_attach_type *attach_type)
{

View File

@ -103,8 +103,13 @@ struct bpf_object_open_opts {
bool relaxed_maps;
/* process CO-RE relocations non-strictly, allowing them to fail */
bool relaxed_core_relocs;
/* maps that set the 'pinning' attribute in their definition will have
* their pin_path attribute set to a file in this directory, and be
* auto-pinned to that path on load; defaults to "/sys/fs/bpf".
*/
const char *pin_root_path;
};
#define bpf_object_open_opts__last_field relaxed_core_relocs
#define bpf_object_open_opts__last_field pin_root_path
LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
LIBBPF_API struct bpf_object *
@ -124,6 +129,17 @@ int bpf_object__section_size(const struct bpf_object *obj, const char *name,
__u32 *size);
int bpf_object__variable_offset(const struct bpf_object *obj, const char *name,
__u32 *off);
enum libbpf_pin_type {
LIBBPF_PIN_NONE,
/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
LIBBPF_PIN_BY_NAME,
};
/* pin_maps and unpin_maps can both be called with a NULL path, in which case
* they will use the pin_path attribute of each map (and ignore all maps that
* don't have a pin_path set).
*/
LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
const char *path);
@ -307,6 +323,7 @@ LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
@ -326,6 +343,7 @@ LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
/*
* No need for __attribute__((packed)), all members of 'bpf_map_def'
@ -385,6 +403,9 @@ LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);

View File

@ -193,8 +193,13 @@ LIBBPF_0.0.5 {
LIBBPF_0.0.6 {
global:
bpf_map__get_pin_path;
bpf_map__is_pinned;
bpf_map__set_pin_path;
bpf_object__open_file;
bpf_object__open_mem;
bpf_program__get_expected_attach_type;
bpf_program__get_type;
bpf_program__is_tracing;
bpf_program__set_tracing;
} LIBBPF_0.0.5;

View File

@ -102,6 +102,7 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns,
case BPF_PROG_TYPE_FLOW_DISSECTOR:
case BPF_PROG_TYPE_CGROUP_SYSCTL:
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
case BPF_PROG_TYPE_TRACING:
default:
break;
}

View File

@ -73,6 +73,21 @@ struct xsk_nl_info {
int fd;
};
/* Up until and including Linux 5.3 */
struct xdp_ring_offset_v1 {
__u64 producer;
__u64 consumer;
__u64 desc;
};
/* Up until and including Linux 5.3 */
struct xdp_mmap_offsets_v1 {
struct xdp_ring_offset_v1 rx;
struct xdp_ring_offset_v1 tx;
struct xdp_ring_offset_v1 fr;
struct xdp_ring_offset_v1 cr;
};
int xsk_umem__fd(const struct xsk_umem *umem)
{
return umem ? umem->fd : -EINVAL;
@ -133,6 +148,58 @@ static int xsk_set_xdp_socket_config(struct xsk_socket_config *cfg,
return 0;
}
static void xsk_mmap_offsets_v1(struct xdp_mmap_offsets *off)
{
struct xdp_mmap_offsets_v1 off_v1;
/* getsockopt on a kernel <= 5.3 has no flags fields.
* Copy over the offsets to the correct places in the >=5.4 format
* and put the flags where they would have been on that kernel.
*/
memcpy(&off_v1, off, sizeof(off_v1));
off->rx.producer = off_v1.rx.producer;
off->rx.consumer = off_v1.rx.consumer;
off->rx.desc = off_v1.rx.desc;
off->rx.flags = off_v1.rx.consumer + sizeof(__u32);
off->tx.producer = off_v1.tx.producer;
off->tx.consumer = off_v1.tx.consumer;
off->tx.desc = off_v1.tx.desc;
off->tx.flags = off_v1.tx.consumer + sizeof(__u32);
off->fr.producer = off_v1.fr.producer;
off->fr.consumer = off_v1.fr.consumer;
off->fr.desc = off_v1.fr.desc;
off->fr.flags = off_v1.fr.consumer + sizeof(__u32);
off->cr.producer = off_v1.cr.producer;
off->cr.consumer = off_v1.cr.consumer;
off->cr.desc = off_v1.cr.desc;
off->cr.flags = off_v1.cr.consumer + sizeof(__u32);
}
static int xsk_get_mmap_offsets(int fd, struct xdp_mmap_offsets *off)
{
socklen_t optlen;
int err;
optlen = sizeof(*off);
err = getsockopt(fd, SOL_XDP, XDP_MMAP_OFFSETS, off, &optlen);
if (err)
return err;
if (optlen == sizeof(*off))
return 0;
if (optlen == sizeof(struct xdp_mmap_offsets_v1)) {
xsk_mmap_offsets_v1(off);
return 0;
}
return -EINVAL;
}
int xsk_umem__create_v0_0_4(struct xsk_umem **umem_ptr, void *umem_area,
__u64 size, struct xsk_ring_prod *fill,
struct xsk_ring_cons *comp,
@ -141,7 +208,6 @@ int xsk_umem__create_v0_0_4(struct xsk_umem **umem_ptr, void *umem_area,
struct xdp_mmap_offsets off;
struct xdp_umem_reg mr;
struct xsk_umem *umem;
socklen_t optlen;
void *map;
int err;
@ -190,8 +256,7 @@ int xsk_umem__create_v0_0_4(struct xsk_umem **umem_ptr, void *umem_area,
goto out_socket;
}
optlen = sizeof(off);
err = getsockopt(umem->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen);
err = xsk_get_mmap_offsets(umem->fd, &off);
if (err) {
err = -errno;
goto out_socket;
@ -514,7 +579,6 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
struct sockaddr_xdp sxdp = {};
struct xdp_mmap_offsets off;
struct xsk_socket *xsk;
socklen_t optlen;
int err;
if (!umem || !xsk_ptr || !rx || !tx)
@ -573,8 +637,7 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
}
}
optlen = sizeof(off);
err = getsockopt(xsk->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen);
err = xsk_get_mmap_offsets(xsk->fd, &off);
if (err) {
err = -errno;
goto out_socket;
@ -660,7 +723,6 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
int xsk_umem__delete(struct xsk_umem *umem)
{
struct xdp_mmap_offsets off;
socklen_t optlen;
int err;
if (!umem)
@ -669,8 +731,7 @@ int xsk_umem__delete(struct xsk_umem *umem)
if (umem->refcount)
return -EBUSY;
optlen = sizeof(off);
err = getsockopt(umem->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen);
err = xsk_get_mmap_offsets(umem->fd, &off);
if (!err) {
munmap(umem->fill->ring - off.fr.desc,
off.fr.desc + umem->config.fill_size * sizeof(__u64));
@ -688,7 +749,6 @@ void xsk_socket__delete(struct xsk_socket *xsk)
{
size_t desc_sz = sizeof(struct xdp_desc);
struct xdp_mmap_offsets off;
socklen_t optlen;
int err;
if (!xsk)
@ -699,8 +759,7 @@ void xsk_socket__delete(struct xsk_socket *xsk)
close(xsk->prog_fd);
}
optlen = sizeof(off);
err = getsockopt(xsk->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen);
err = xsk_get_mmap_offsets(xsk->fd, &off);
if (!err) {
if (xsk->rx) {
munmap(xsk->rx->ring - off.rx.desc,

View File

@ -89,6 +89,9 @@ $(notdir $(TEST_GEN_PROGS) \
$(OUTPUT)/urandom_read: urandom_read.c
$(CC) -o $@ $< -Wl,--build-id
$(OUTPUT)/test_stub.o: test_stub.c
$(CC) -c $(CFLAGS) -o $@ $<
BPFOBJ := $(OUTPUT)/libbpf.a
$(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED): $(OUTPUT)/test_stub.o $(BPFOBJ)
@ -131,8 +134,13 @@ $(shell $(1) -v -E - </dev/null 2>&1 \
| sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }')
endef
# Determine target endianness.
IS_LITTLE_ENDIAN = $(shell $(CC) -dM -E - </dev/null | \
grep 'define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__')
MENDIAN=$(if $(IS_LITTLE_ENDIAN),-mlittle-endian,-mbig-endian)
CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
BPF_CFLAGS = -g -D__TARGET_ARCH_$(SRCARCH) \
BPF_CFLAGS = -g -D__TARGET_ARCH_$(SRCARCH) $(MENDIAN) \
-I. -I./include/uapi -I$(APIDIR) \
-I$(BPFDIR) -I$(abspath $(OUTPUT)/../usr/include)
@ -271,12 +279,8 @@ $(eval $(call DEFINE_TEST_RUNNER,test_progs,no_alu32))
# Define test_progs BPF-GCC-flavored test runner.
ifneq ($(BPF_GCC),)
IS_LITTLE_ENDIAN = $(shell $(CC) -dM -E - </dev/null | \
grep 'define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__')
MENDIAN=$(if $(IS_LITTLE_ENDIAN),-mlittle-endian,-mbig-endian)
TRUNNER_BPF_BUILD_RULE := GCC_BPF_BUILD_RULE
TRUNNER_BPF_CFLAGS := $(BPF_CFLAGS) $(call get_sys_includes,gcc) $(MENDIAN)
TRUNNER_BPF_CFLAGS := $(BPF_CFLAGS) $(call get_sys_includes,gcc)
TRUNNER_BPF_LDFLAGS :=
$(eval $(call DEFINE_TEST_RUNNER,test_progs,bpf_gcc))
endif

View File

@ -0,0 +1,210 @@
// SPDX-License-Identifier: GPL-2.0
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <test_progs.h>
__u32 get_map_id(struct bpf_object *obj, const char *name)
{
struct bpf_map_info map_info = {};
__u32 map_info_len, duration = 0;
struct bpf_map *map;
int err;
map_info_len = sizeof(map_info);
map = bpf_object__find_map_by_name(obj, name);
if (CHECK(!map, "find map", "NULL map"))
return 0;
err = bpf_obj_get_info_by_fd(bpf_map__fd(map),
&map_info, &map_info_len);
CHECK(err, "get map info", "err %d errno %d", err, errno);
return map_info.id;
}
void test_pinning(void)
{
const char *file_invalid = "./test_pinning_invalid.o";
const char *custpinpath = "/sys/fs/bpf/custom/pinmap";
const char *nopinpath = "/sys/fs/bpf/nopinmap";
const char *nopinpath2 = "/sys/fs/bpf/nopinmap2";
const char *custpath = "/sys/fs/bpf/custom";
const char *pinpath = "/sys/fs/bpf/pinmap";
const char *file = "./test_pinning.o";
__u32 map_id, map_id2, duration = 0;
struct stat statbuf = {};
struct bpf_object *obj;
struct bpf_map *map;
int err;
DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts,
.pin_root_path = custpath,
);
/* check that opening fails with invalid pinning value in map def */
obj = bpf_object__open_file(file_invalid, NULL);
err = libbpf_get_error(obj);
if (CHECK(err != -EINVAL, "invalid open", "err %d errno %d\n", err, errno)) {
obj = NULL;
goto out;
}
/* open the valid object file */
obj = bpf_object__open_file(file, NULL);
err = libbpf_get_error(obj);
if (CHECK(err, "default open", "err %d errno %d\n", err, errno)) {
obj = NULL;
goto out;
}
err = bpf_object__load(obj);
if (CHECK(err, "default load", "err %d errno %d\n", err, errno))
goto out;
/* check that pinmap was pinned */
err = stat(pinpath, &statbuf);
if (CHECK(err, "stat pinpath", "err %d errno %d\n", err, errno))
goto out;
/* check that nopinmap was *not* pinned */
err = stat(nopinpath, &statbuf);
if (CHECK(!err || errno != ENOENT, "stat nopinpath",
"err %d errno %d\n", err, errno))
goto out;
/* check that nopinmap2 was *not* pinned */
err = stat(nopinpath2, &statbuf);
if (CHECK(!err || errno != ENOENT, "stat nopinpath2",
"err %d errno %d\n", err, errno))
goto out;
map_id = get_map_id(obj, "pinmap");
if (!map_id)
goto out;
bpf_object__close(obj);
obj = bpf_object__open_file(file, NULL);
if (CHECK_FAIL(libbpf_get_error(obj))) {
obj = NULL;
goto out;
}
err = bpf_object__load(obj);
if (CHECK(err, "default load", "err %d errno %d\n", err, errno))
goto out;
/* check that same map ID was reused for second load */
map_id2 = get_map_id(obj, "pinmap");
if (CHECK(map_id != map_id2, "check reuse",
"err %d errno %d id %d id2 %d\n", err, errno, map_id, map_id2))
goto out;
/* should be no-op to re-pin same map */
map = bpf_object__find_map_by_name(obj, "pinmap");
if (CHECK(!map, "find map", "NULL map"))
goto out;
err = bpf_map__pin(map, NULL);
if (CHECK(err, "re-pin map", "err %d errno %d\n", err, errno))
goto out;
/* but error to pin at different location */
err = bpf_map__pin(map, "/sys/fs/bpf/other");
if (CHECK(!err, "pin map different", "err %d errno %d\n", err, errno))
goto out;
/* unpin maps with a pin_path set */
err = bpf_object__unpin_maps(obj, NULL);
if (CHECK(err, "unpin maps", "err %d errno %d\n", err, errno))
goto out;
/* and re-pin them... */
err = bpf_object__pin_maps(obj, NULL);
if (CHECK(err, "pin maps", "err %d errno %d\n", err, errno))
goto out;
/* set pinning path of other map and re-pin all */
map = bpf_object__find_map_by_name(obj, "nopinmap");
if (CHECK(!map, "find map", "NULL map"))
goto out;
err = bpf_map__set_pin_path(map, custpinpath);
if (CHECK(err, "set pin path", "err %d errno %d\n", err, errno))
goto out;
/* should only pin the one unpinned map */
err = bpf_object__pin_maps(obj, NULL);
if (CHECK(err, "pin maps", "err %d errno %d\n", err, errno))
goto out;
/* check that nopinmap was pinned at the custom path */
err = stat(custpinpath, &statbuf);
if (CHECK(err, "stat custpinpath", "err %d errno %d\n", err, errno))
goto out;
/* remove the custom pin path to re-test it with auto-pinning below */
err = unlink(custpinpath);
if (CHECK(err, "unlink custpinpath", "err %d errno %d\n", err, errno))
goto out;
err = rmdir(custpath);
if (CHECK(err, "rmdir custpindir", "err %d errno %d\n", err, errno))
goto out;
bpf_object__close(obj);
/* open the valid object file again */
obj = bpf_object__open_file(file, NULL);
err = libbpf_get_error(obj);
if (CHECK(err, "default open", "err %d errno %d\n", err, errno)) {
obj = NULL;
goto out;
}
/* swap pin paths of the two maps */
bpf_object__for_each_map(map, obj) {
if (!strcmp(bpf_map__name(map), "nopinmap"))
err = bpf_map__set_pin_path(map, pinpath);
else if (!strcmp(bpf_map__name(map), "pinmap"))
err = bpf_map__set_pin_path(map, NULL);
else
continue;
if (CHECK(err, "set pin path", "err %d errno %d\n", err, errno))
goto out;
}
/* should fail because of map parameter mismatch */
err = bpf_object__load(obj);
if (CHECK(err != -EINVAL, "param mismatch load", "err %d errno %d\n", err, errno))
goto out;
bpf_object__close(obj);
/* test auto-pinning at custom path with open opt */
obj = bpf_object__open_file(file, &opts);
if (CHECK_FAIL(libbpf_get_error(obj))) {
obj = NULL;
goto out;
}
err = bpf_object__load(obj);
if (CHECK(err, "custom load", "err %d errno %d\n", err, errno))
goto out;
/* check that pinmap was pinned at the custom path */
err = stat(custpinpath, &statbuf);
if (CHECK(err, "stat custpinpath", "err %d errno %d\n", err, errno))
goto out;
out:
unlink(pinpath);
unlink(nopinpath);
unlink(nopinpath2);
unlink(custpinpath);
rmdir(custpath);
if (obj)
bpf_object__close(obj);
}

View File

@ -0,0 +1,78 @@
// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
void test_probe_user(void)
{
#define kprobe_name "__sys_connect"
const char *prog_name = "kprobe/" kprobe_name;
const char *obj_file = "./test_probe_user.o";
DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, );
int err, results_map_fd, sock_fd, duration = 0;
struct sockaddr curr, orig, tmp;
struct sockaddr_in *in = (struct sockaddr_in *)&curr;
struct bpf_link *kprobe_link = NULL;
struct bpf_program *kprobe_prog;
struct bpf_object *obj;
static const int zero = 0;
obj = bpf_object__open_file(obj_file, &opts);
if (CHECK(IS_ERR(obj), "obj_open_file", "err %ld\n", PTR_ERR(obj)))
return;
kprobe_prog = bpf_object__find_program_by_title(obj, prog_name);
if (CHECK(!kprobe_prog, "find_probe",
"prog '%s' not found\n", prog_name))
goto cleanup;
err = bpf_object__load(obj);
if (CHECK(err, "obj_load", "err %d\n", err))
goto cleanup;
results_map_fd = bpf_find_map(__func__, obj, "test_pro.bss");
if (CHECK(results_map_fd < 0, "find_bss_map",
"err %d\n", results_map_fd))
goto cleanup;
kprobe_link = bpf_program__attach_kprobe(kprobe_prog, false,
kprobe_name);
if (CHECK(IS_ERR(kprobe_link), "attach_kprobe",
"err %ld\n", PTR_ERR(kprobe_link))) {
kprobe_link = NULL;
goto cleanup;
}
memset(&curr, 0, sizeof(curr));
in->sin_family = AF_INET;
in->sin_port = htons(5555);
in->sin_addr.s_addr = inet_addr("255.255.255.255");
memcpy(&orig, &curr, sizeof(curr));
sock_fd = socket(AF_INET, SOCK_STREAM, 0);
if (CHECK(sock_fd < 0, "create_sock_fd", "err %d\n", sock_fd))
goto cleanup;
connect(sock_fd, &curr, sizeof(curr));
close(sock_fd);
err = bpf_map_lookup_elem(results_map_fd, &zero, &tmp);
if (CHECK(err, "get_kprobe_res",
"failed to get kprobe res: %d\n", err))
goto cleanup;
in = (struct sockaddr_in *)&tmp;
if (CHECK(memcmp(&tmp, &orig, sizeof(orig)), "check_kprobe_res",
"wrong kprobe res from probe read: %s:%u\n",
inet_ntoa(in->sin_addr), ntohs(in->sin_port)))
goto cleanup;
memset(&tmp, 0xab, sizeof(tmp));
in = (struct sockaddr_in *)&curr;
if (CHECK(memcmp(&curr, &tmp, sizeof(tmp)), "check_kprobe_res",
"wrong kprobe res from probe write: %s:%u\n",
inet_ntoa(in->sin_addr), ntohs(in->sin_port)))
goto cleanup;
cleanup:
bpf_link__destroy(kprobe_link);
bpf_object__close(obj);
}

View File

@ -79,11 +79,11 @@ int trace_kfree_skb(struct trace_kfree_skb *ctx)
func = ptr->func;
}));
bpf_probe_read(&pkt_type, sizeof(pkt_type), _(&skb->__pkt_type_offset));
bpf_probe_read_kernel(&pkt_type, sizeof(pkt_type), _(&skb->__pkt_type_offset));
pkt_type &= 7;
/* read eth proto */
bpf_probe_read(&pkt_data, sizeof(pkt_data), data + 12);
bpf_probe_read_kernel(&pkt_data, sizeof(pkt_data), data + 12);
bpf_printk("rcuhead.next %llx func %llx\n", ptr, func);
bpf_printk("skb->len %d users %d pkt_type %x\n",

View File

@ -72,8 +72,8 @@ static __always_inline void *get_thread_state(void *tls_base, PidData *pidData)
void* thread_state;
int key;
bpf_probe_read(&key, sizeof(key), (void*)(long)pidData->tls_key_addr);
bpf_probe_read(&thread_state, sizeof(thread_state),
bpf_probe_read_user(&key, sizeof(key), (void*)(long)pidData->tls_key_addr);
bpf_probe_read_user(&thread_state, sizeof(thread_state),
tls_base + 0x310 + key * 0x10 + 0x08);
return thread_state;
}
@ -82,31 +82,33 @@ static __always_inline bool get_frame_data(void *frame_ptr, PidData *pidData,
FrameData *frame, Symbol *symbol)
{
// read data from PyFrameObject
bpf_probe_read(&frame->f_back,
bpf_probe_read_user(&frame->f_back,
sizeof(frame->f_back),
frame_ptr + pidData->offsets.PyFrameObject_back);
bpf_probe_read(&frame->f_code,
bpf_probe_read_user(&frame->f_code,
sizeof(frame->f_code),
frame_ptr + pidData->offsets.PyFrameObject_code);
// read data from PyCodeObject
if (!frame->f_code)
return false;
bpf_probe_read(&frame->co_filename,
bpf_probe_read_user(&frame->co_filename,
sizeof(frame->co_filename),
frame->f_code + pidData->offsets.PyCodeObject_filename);
bpf_probe_read(&frame->co_name,
bpf_probe_read_user(&frame->co_name,
sizeof(frame->co_name),
frame->f_code + pidData->offsets.PyCodeObject_name);
// read actual names into symbol
if (frame->co_filename)
bpf_probe_read_str(&symbol->file,
bpf_probe_read_user_str(&symbol->file,
sizeof(symbol->file),
frame->co_filename + pidData->offsets.String_data);
frame->co_filename +
pidData->offsets.String_data);
if (frame->co_name)
bpf_probe_read_str(&symbol->name,
bpf_probe_read_user_str(&symbol->name,
sizeof(symbol->name),
frame->co_name + pidData->offsets.String_data);
frame->co_name +
pidData->offsets.String_data);
return true;
}
@ -174,7 +176,7 @@ static __always_inline int __on_event(struct pt_regs *ctx)
event->kernel_stack_id = bpf_get_stackid(ctx, &stackmap, 0);
void* thread_state_current = (void*)0;
bpf_probe_read(&thread_state_current,
bpf_probe_read_user(&thread_state_current,
sizeof(thread_state_current),
(void*)(long)pidData->current_state_addr);
@ -188,11 +190,13 @@ static __always_inline int __on_event(struct pt_regs *ctx)
if (pidData->use_tls) {
uint64_t pthread_created;
uint64_t pthread_self;
bpf_probe_read(&pthread_self, sizeof(pthread_self), tls_base + 0x10);
bpf_probe_read_user(&pthread_self, sizeof(pthread_self),
tls_base + 0x10);
bpf_probe_read(&pthread_created,
bpf_probe_read_user(&pthread_created,
sizeof(pthread_created),
thread_state + pidData->offsets.PyThreadState_thread);
thread_state +
pidData->offsets.PyThreadState_thread);
event->pthread_match = pthread_created == pthread_self;
} else {
event->pthread_match = 1;
@ -204,9 +208,10 @@ static __always_inline int __on_event(struct pt_regs *ctx)
Symbol sym = {};
int cur_cpu = bpf_get_smp_processor_id();
bpf_probe_read(&frame_ptr,
bpf_probe_read_user(&frame_ptr,
sizeof(frame_ptr),
thread_state + pidData->offsets.PyThreadState_frame);
thread_state +
pidData->offsets.PyThreadState_frame);
int32_t* symbol_counter = bpf_map_lookup_elem(&symbolmap, &sym);
if (symbol_counter == NULL)

View File

@ -98,7 +98,7 @@ struct strobe_map_raw {
/*
* having volatile doesn't change anything on BPF side, but clang
* emits warnings for passing `volatile const char *` into
* bpf_probe_read_str that expects just `const char *`
* bpf_probe_read_user_str that expects just `const char *`
*/
const char* tag;
/*
@ -309,18 +309,18 @@ static __always_inline void *calc_location(struct strobe_value_loc *loc,
dtv_t *dtv;
void *tls_ptr;
bpf_probe_read(&tls_index, sizeof(struct tls_index),
bpf_probe_read_user(&tls_index, sizeof(struct tls_index),
(void *)loc->offset);
/* valid module index is always positive */
if (tls_index.module > 0) {
/* dtv = ((struct tcbhead *)tls_base)->dtv[tls_index.module] */
bpf_probe_read(&dtv, sizeof(dtv),
bpf_probe_read_user(&dtv, sizeof(dtv),
&((struct tcbhead *)tls_base)->dtv);
dtv += tls_index.module;
} else {
dtv = NULL;
}
bpf_probe_read(&tls_ptr, sizeof(void *), dtv);
bpf_probe_read_user(&tls_ptr, sizeof(void *), dtv);
/* if pointer has (void *)-1 value, then TLS wasn't initialized yet */
return tls_ptr && tls_ptr != (void *)-1
? tls_ptr + tls_index.offset
@ -336,7 +336,7 @@ static __always_inline void read_int_var(struct strobemeta_cfg *cfg,
if (!location)
return;
bpf_probe_read(value, sizeof(struct strobe_value_generic), location);
bpf_probe_read_user(value, sizeof(struct strobe_value_generic), location);
data->int_vals[idx] = value->val;
if (value->header.len)
data->int_vals_set_mask |= (1 << idx);
@ -356,13 +356,13 @@ static __always_inline uint64_t read_str_var(struct strobemeta_cfg *cfg,
if (!location)
return 0;
bpf_probe_read(value, sizeof(struct strobe_value_generic), location);
len = bpf_probe_read_str(payload, STROBE_MAX_STR_LEN, value->ptr);
bpf_probe_read_user(value, sizeof(struct strobe_value_generic), location);
len = bpf_probe_read_user_str(payload, STROBE_MAX_STR_LEN, value->ptr);
/*
* if bpf_probe_read_str returns error (<0), due to casting to
* if bpf_probe_read_user_str returns error (<0), due to casting to
* unsinged int, it will become big number, so next check is
* sufficient to check for errors AND prove to BPF verifier, that
* bpf_probe_read_str won't return anything bigger than
* bpf_probe_read_user_str won't return anything bigger than
* STROBE_MAX_STR_LEN
*/
if (len > STROBE_MAX_STR_LEN)
@ -391,8 +391,8 @@ static __always_inline void *read_map_var(struct strobemeta_cfg *cfg,
if (!location)
return payload;
bpf_probe_read(value, sizeof(struct strobe_value_generic), location);
if (bpf_probe_read(&map, sizeof(struct strobe_map_raw), value->ptr))
bpf_probe_read_user(value, sizeof(struct strobe_value_generic), location);
if (bpf_probe_read_user(&map, sizeof(struct strobe_map_raw), value->ptr))
return payload;
descr->id = map.id;
@ -402,7 +402,7 @@ static __always_inline void *read_map_var(struct strobemeta_cfg *cfg,
data->req_meta_valid = 1;
}
len = bpf_probe_read_str(payload, STROBE_MAX_STR_LEN, map.tag);
len = bpf_probe_read_user_str(payload, STROBE_MAX_STR_LEN, map.tag);
if (len <= STROBE_MAX_STR_LEN) {
descr->tag_len = len;
payload += len;
@ -418,14 +418,14 @@ static __always_inline void *read_map_var(struct strobemeta_cfg *cfg,
break;
descr->key_lens[i] = 0;
len = bpf_probe_read_str(payload, STROBE_MAX_STR_LEN,
len = bpf_probe_read_user_str(payload, STROBE_MAX_STR_LEN,
map.entries[i].key);
if (len <= STROBE_MAX_STR_LEN) {
descr->key_lens[i] = len;
payload += len;
}
descr->val_lens[i] = 0;
len = bpf_probe_read_str(payload, STROBE_MAX_STR_LEN,
len = bpf_probe_read_user_str(payload, STROBE_MAX_STR_LEN,
map.entries[i].val);
if (len <= STROBE_MAX_STR_LEN) {
descr->val_lens[i] = len;

View File

@ -0,0 +1,31 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include "bpf_helpers.h"
int _version SEC("version") = 1;
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
__uint(pinning, LIBBPF_PIN_BY_NAME);
} pinmap SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
} nopinmap SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
__uint(pinning, LIBBPF_PIN_NONE);
} nopinmap2 SEC(".maps");
char _license[] SEC("license") = "GPL";

View File

@ -0,0 +1,16 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include "bpf_helpers.h"
int _version SEC("version") = 1;
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
__uint(pinning, 2); /* invalid */
} nopinmap3 SEC(".maps");
char _license[] SEC("license") = "GPL";

View File

@ -0,0 +1,26 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/ptrace.h>
#include <linux/bpf.h>
#include <netinet/in.h>
#include "bpf_helpers.h"
#include "bpf_tracing.h"
static struct sockaddr_in old;
SEC("kprobe/__sys_connect")
int handle_sys_connect(struct pt_regs *ctx)
{
void *ptr = (void *)PT_REGS_PARM2(ctx);
struct sockaddr_in new;
bpf_probe_read_user(&old, sizeof(old), ptr);
__builtin_memset(&new, 0xab, sizeof(new));
bpf_probe_write_user(ptr, &new, sizeof(new));
return 0;
}
char _license[] SEC("license") = "GPL";

View File

@ -38,7 +38,7 @@
#include <sys/socket.h>
#include "bpf_helpers.h"
#define _(P) ({typeof(P) val = 0; bpf_probe_read(&val, sizeof(val), &P); val;})
#define _(P) ({typeof(P) val = 0; bpf_probe_read_kernel(&val, sizeof(val), &P); val;})
#define TCP_ESTATS_MAGIC 0xBAADBEEF
/* This test case needs "sock" and "pt_regs" data structure.

View File

@ -314,9 +314,6 @@ class DebugfsDir:
continue
p = os.path.join(path, f)
if not os.stat(p).st_mode & stat.S_IRUSR:
continue
if os.path.isfile(p) and os.access(p, os.R_OK):
_, out = cmd('cat %s/%s' % (path, f))
dfs[f] = out.strip()

View File

@ -120,6 +120,29 @@ static struct sysctl_test tests[] = {
.newval = "(none)", /* same as default, should fail anyway */
.result = OP_EPERM,
},
{
.descr = "ctx:write sysctl:write read ok narrow",
.insns = {
/* u64 w = (u16)write & 1; */
#if __BYTE_ORDER == __LITTLE_ENDIAN
BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_1,
offsetof(struct bpf_sysctl, write)),
#else
BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_1,
offsetof(struct bpf_sysctl, write) + 2),
#endif
BPF_ALU64_IMM(BPF_AND, BPF_REG_7, 1),
/* return 1 - w; */
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_7),
BPF_EXIT_INSN(),
},
.attach_type = BPF_CGROUP_SYSCTL,
.sysctl = "kernel/domainname",
.open_flags = O_WRONLY,
.newval = "(none)", /* same as default, should fail anyway */
.result = OP_EPERM,
},
{
.descr = "ctx:write sysctl:read write reject",
.insns = {