commit ba6e31af2be96c4d0536f2152ed6f7b6c11bca47 upstream.
RSB fill sequence does not have any protection for miss-prediction of
conditional branch at the end of the sequence. CPU can speculatively
execute code immediately after the sequence, while RSB filling hasn't
completed yet.
#define __FILL_RETURN_BUFFER(reg, nr, sp) \
mov $(nr/2), reg; \
771: \
ANNOTATE_INTRA_FUNCTION_CALL; \
call 772f; \
773: /* speculation trap */ \
UNWIND_HINT_EMPTY; \
pause; \
lfence; \
jmp 773b; \
772: \
ANNOTATE_INTRA_FUNCTION_CALL; \
call 774f; \
775: /* speculation trap */ \
UNWIND_HINT_EMPTY; \
pause; \
lfence; \
jmp 775b; \
774: \
add $(BITS_PER_LONG/8) * 2, sp; \
dec reg; \
jnz 771b; <----- CPU can miss-predict here.
Before RSB is filled, RETs that come in program order after this macro
can be executed speculatively, making them vulnerable to RSB-based
attacks.
Mitigate it by adding an LFENCE after the conditional branch to prevent
speculation while RSB is being filled.
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2b1299322016731d56807aa49254a5ea3080b6b3 upstream.
tl;dr: The Enhanced IBRS mitigation for Spectre v2 does not work as
documented for RET instructions after VM exits. Mitigate it with a new
one-entry RSB stuffing mechanism and a new LFENCE.
== Background ==
Indirect Branch Restricted Speculation (IBRS) was designed to help
mitigate Branch Target Injection and Speculative Store Bypass, i.e.
Spectre, attacks. IBRS prevents software run in less privileged modes
from affecting branch prediction in more privileged modes. IBRS requires
the MSR to be written on every privilege level change.
To overcome some of the performance issues of IBRS, Enhanced IBRS was
introduced. eIBRS is an "always on" IBRS, in other words, just turn
it on once instead of writing the MSR on every privilege level change.
When eIBRS is enabled, more privileged modes should be protected from
less privileged modes, including protecting VMMs from guests.
== Problem ==
Here's a simplification of how guests are run on Linux' KVM:
void run_kvm_guest(void)
{
// Prepare to run guest
VMRESUME();
// Clean up after guest runs
}
The execution flow for that would look something like this to the
processor:
1. Host-side: call run_kvm_guest()
2. Host-side: VMRESUME
3. Guest runs, does "CALL guest_function"
4. VM exit, host runs again
5. Host might make some "cleanup" function calls
6. Host-side: RET from run_kvm_guest()
Now, when back on the host, there are a couple of possible scenarios of
post-guest activity the host needs to do before executing host code:
* on pre-eIBRS hardware (legacy IBRS, or nothing at all), the RSB is not
touched and Linux has to do a 32-entry stuffing.
* on eIBRS hardware, VM exit with IBRS enabled, or restoring the host
IBRS=1 shortly after VM exit, has a documented side effect of flushing
the RSB except in this PBRSB situation where the software needs to stuff
the last RSB entry "by hand".
IOW, with eIBRS supported, host RET instructions should no longer be
influenced by guest behavior after the host retires a single CALL
instruction.
However, if the RET instructions are "unbalanced" with CALLs after a VM
exit as is the RET in #6, it might speculatively use the address for the
instruction after the CALL in #3 as an RSB prediction. This is a problem
since the (untrusted) guest controls this address.
Balanced CALL/RET instruction pairs such as in step #5 are not affected.
== Solution ==
The PBRSB issue affects a wide variety of Intel processors which
support eIBRS. But not all of them need mitigation. Today,
X86_FEATURE_RSB_VMEXIT triggers an RSB filling sequence that mitigates
PBRSB. Systems setting RSB_VMEXIT need no further mitigation - i.e.,
eIBRS systems which enable legacy IBRS explicitly.
However, such systems (X86_FEATURE_IBRS_ENHANCED) do not set RSB_VMEXIT
and most of them need a new mitigation.
Therefore, introduce a new feature flag X86_FEATURE_RSB_VMEXIT_LITE
which triggers a lighter-weight PBRSB mitigation versus RSB_VMEXIT.
The lighter-weight mitigation performs a CALL instruction which is
immediately followed by a speculative execution barrier (INT3). This
steers speculative execution to the barrier -- just like a retpoline
-- which ensures that speculation can never reach an unbalanced RET.
Then, ensure this CALL is retired before continuing execution with an
LFENCE.
In other words, the window of exposure is opened at VM exit where RET
behavior is troublesome. While the window is open, force RSB predictions
sampling for RET targets to a dead end at the INT3. Close the window
with the LFENCE.
There is a subset of eIBRS systems which are not vulnerable to PBRSB.
Add these systems to the cpu_vuln_whitelist[] as NO_EIBRS_PBRSB.
Future systems that aren't vulnerable will set ARCH_CAP_PBRSB_NO.
[ bp: Massage, incorporate review comments from Andy Cooper. ]
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Co-developed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fd97e4ad6d3b0c9fce3bca8ea8e6969d9ce7423b upstream.
In do_adb_query() function of drivers/macintosh/adb.c, req->data is copied
form userland. The parameter "req->data[2]" is missing check, the array
size of adb_handler[] is 16, so adb_handler[req->data[2]].original_address and
adb_handler[req->data[2]].handler_id will lead to oob read.
Cc: stable <stable@kernel.org>
Signed-off-by: Ning Qiang <sohu0106@126.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220713153734.2248-1-sohu0106@126.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4f17c2b6694d0c4098f33b07ee3a696976940aa5 upstream.
The BCM4349B1, aka CYW/BCM89359, is a WiFi+BT chip and its Bluetooth
portion can be controlled over serial.
Two subversions are added for the chip, because ROM firmware reports
002.002.013 (at least for the chips I have here), while depending on
patchram firmware revision, either 002.002.013 or 002.002.014 is
reported.
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9e2f6498efbbc880d7caa7935839e682b64fe5a6 ]
The selftests, when built with newer versions of clang, is found
to have over optimized guests' ucall() function, and eliminating
the stores for uc.cmd (perhaps due to no immediate readers). This
resulted in the userspace side always reading a value of '0', and
causing multiple test failures.
As a result, prevent the compiler from optimizing the stores in
ucall() with WRITE_ONCE().
Suggested-by: Ricardo Koller <ricarkol@google.com>
Suggested-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Message-Id: <20220615185706.1099208-1-rananta@google.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 933b5f9f98da29af646b51b36a0753692908ef64 ]
Instead of printing an error message, kvm_stat script fails when we
restrict statistics to a guest by its name and there are multiple guests
with such name:
# kvm_stat -g my_vm
Traceback (most recent call last):
File "/usr/bin/kvm_stat", line 1819, in <module>
main()
File "/usr/bin/kvm_stat", line 1779, in main
options = get_options()
File "/usr/bin/kvm_stat", line 1718, in get_options
options = argparser.parse_args()
File "/usr/lib64/python3.10/argparse.py", line 1825, in parse_args
args, argv = self.parse_known_args(args, namespace)
File "/usr/lib64/python3.10/argparse.py", line 1858, in parse_known_args
namespace, args = self._parse_known_args(args, namespace)
File "/usr/lib64/python3.10/argparse.py", line 2067, in _parse_known_args
start_index = consume_optional(start_index)
File "/usr/lib64/python3.10/argparse.py", line 2007, in consume_optional
take_action(action, args, option_string)
File "/usr/lib64/python3.10/argparse.py", line 1935, in take_action
action(self, namespace, argument_values, option_string)
File "/usr/bin/kvm_stat", line 1649, in __call__
' to specify the desired pid'.format(" ".join(pids)))
TypeError: sequence item 0: expected str instance, int found
To avoid this, it's needed to convert pids int values to strings before
pass them to join().
Signed-off-by: Dmitry Klochkov <kdmitry556@gmail.com>
Message-Id: <20220614121141.160689-1-kdmitry556@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7ae19d422c7da84b5f13bc08b98bd737a08d3a53 upstream.
A kasan error was reported during fuzzing:
BUG: KASAN: slab-out-of-bounds in neon_poly1305_blocks.constprop.0+0x1b4/0x250 [poly1305_neon]
Read of size 4 at addr ffff0010e293f010 by task syz-executor.5/1646715
CPU: 4 PID: 1646715 Comm: syz-executor.5 Kdump: loaded Not tainted 5.10.0.aarch64 #1
Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.59 01/31/2019
Call trace:
dump_backtrace+0x0/0x394
show_stack+0x34/0x4c arch/arm64/kernel/stacktrace.c:196
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x158/0x1e4 lib/dump_stack.c:118
print_address_description.constprop.0+0x68/0x204 mm/kasan/report.c:387
__kasan_report+0xe0/0x140 mm/kasan/report.c:547
kasan_report+0x44/0xe0 mm/kasan/report.c:564
check_memory_region_inline mm/kasan/generic.c:187 [inline]
__asan_load4+0x94/0xd0 mm/kasan/generic.c:252
neon_poly1305_blocks.constprop.0+0x1b4/0x250 [poly1305_neon]
neon_poly1305_do_update+0x6c/0x15c [poly1305_neon]
neon_poly1305_update+0x9c/0x1c4 [poly1305_neon]
crypto_shash_update crypto/shash.c:131 [inline]
shash_finup_unaligned+0x84/0x15c crypto/shash.c:179
crypto_shash_finup+0x8c/0x140 crypto/shash.c:193
shash_digest_unaligned+0xb8/0xe4 crypto/shash.c:201
crypto_shash_digest+0xa4/0xfc crypto/shash.c:217
crypto_shash_tfm_digest+0xb4/0x150 crypto/shash.c:229
essiv_skcipher_setkey+0x164/0x200 [essiv]
crypto_skcipher_setkey+0xb0/0x160 crypto/skcipher.c:612
skcipher_setkey+0x3c/0x50 crypto/algif_skcipher.c:305
alg_setkey+0x114/0x2a0 crypto/af_alg.c:220
alg_setsockopt+0x19c/0x210 crypto/af_alg.c:253
__sys_setsockopt+0x190/0x2e0 net/socket.c:2123
__do_sys_setsockopt net/socket.c:2134 [inline]
__se_sys_setsockopt net/socket.c:2131 [inline]
__arm64_sys_setsockopt+0x78/0x94 net/socket.c:2131
__invoke_syscall arch/arm64/kernel/syscall.c:36 [inline]
invoke_syscall+0x64/0x100 arch/arm64/kernel/syscall.c:48
el0_svc_common.constprop.0+0x220/0x230 arch/arm64/kernel/syscall.c:155
do_el0_svc+0xb4/0xd4 arch/arm64/kernel/syscall.c:217
el0_svc+0x24/0x3c arch/arm64/kernel/entry-common.c:353
el0_sync_handler+0x160/0x164 arch/arm64/kernel/entry-common.c:369
el0_sync+0x160/0x180 arch/arm64/kernel/entry.S:683
This error can be reproduced by the following code compiled as ko on a
system with kasan enabled:
#include <linux/module.h>
#include <linux/crypto.h>
#include <crypto/hash.h>
#include <crypto/poly1305.h>
char test_data[] = "\x00\x01\x02\x03\x04\x05\x06\x07"
"\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
"\x10\x11\x12\x13\x14\x15\x16\x17"
"\x18\x19\x1a\x1b\x1c\x1d\x1e";
int init(void)
{
struct crypto_shash *tfm = NULL;
char *data = NULL, *out = NULL;
tfm = crypto_alloc_shash("poly1305", 0, 0);
data = kmalloc(POLY1305_KEY_SIZE - 1, GFP_KERNEL);
out = kmalloc(POLY1305_DIGEST_SIZE, GFP_KERNEL);
memcpy(data, test_data, POLY1305_KEY_SIZE - 1);
crypto_shash_tfm_digest(tfm, data, POLY1305_KEY_SIZE - 1, out);
kfree(data);
kfree(out);
return 0;
}
void deinit(void)
{
}
module_init(init)
module_exit(deinit)
MODULE_LICENSE("GPL");
The root cause of the bug sits in neon_poly1305_blocks. The logic
neon_poly1305_blocks() performed is that if it was called with both s[]
and r[] uninitialized, it will first try to initialize them with the
data from the first "block" that it believed to be 32 bytes in length.
First 16 bytes are used as the key and the next 16 bytes for s[]. This
would lead to the aforementioned read out-of-bound. However, after
calling poly1305_init_arch(), only 16 bytes were deducted from the input
and s[] is initialized yet again with the following 16 bytes. The second
initialization of s[] is certainly redundent which indicates that the
first initialization should be for r[] only.
This patch fixes the issue by calling poly1305_init_arm64() instead of
poly1305_init_arch(). This is also the implementation for the same
algorithm on arm platform.
Fixes: f569ca1647 ("crypto: arm64/poly1305 - incorporate OpenSSL/CRYPTOGAMS NEON implementation")
Cc: stable@vger.kernel.org
Signed-off-by: GUO Zihua <guozihua@huawei.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c3481b6b75b4797657838f44028fd28226ab48e0 upstream.
The fix in commit 3f8dec116210 ("ACPI/APEI: Limit printable size of BERT
table data") does not work as intended on systems where the BIOS has a
fixed size block of memory for the BERT table, relying on s/w to quit
when it finds a record with estatus->block_status == 0. On these systems
all errors are suppressed because the check:
if (region_len < ACPI_BERT_PRINT_MAX_LEN)
always fails.
New scheme skips individual CPER records that are too large, and also
limits the total number of records that will be printed to 5.
Fixes: 3f8dec116210 ("ACPI/APEI: Limit printable size of BERT table data")
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f0341e67b3782603737f7788e71bd3530012a4f4 upstream.
Taking a recent change in the i8042 quirklist to this one: Clevo
board_names are somewhat unique, and if not: The generic Board_-/Sys_Vendor
string "Notebook" doesn't help much anyway. So identifying the devices just
by the board_name helps keeping the list significantly shorter and might
even hit more devices requiring the fix.
Signed-off-by: Werner Sembach <wse@tuxedocomputers.com>
Fixes: c844d22fe0c0 ("ACPI: video: Force backlight native for Clevo NL5xRU and NL5xNU")
Cc: All applicable <stable@vger.kernel.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c752089f7cf5b5800c6ace4cdd1a8351ee78a598 upstream.
The TongFang PF5PU1G, PF4NU1F, PF5NU1G, and PF5LUXG/TUXEDO BA15 Gen10,
Pulse 14/15 Gen1, and Pulse 15 Gen2 have the same problem as the Clevo
NL5xRU and NL5xNU/TUXEDO Aura 15 Gen1 and Gen2:
They have a working native and video interface. However the default
detection mechanism first registers the video interface before
unregistering it again and switching to the native interface during boot.
This results in a dangling SBIOS request for backlight change for some
reason, causing the backlight to switch to ~2% once per boot on the first
power cord connect or disconnect event. Setting the native interface
explicitly circumvents this buggy behaviour by avoiding the unregistering
process.
Signed-off-by: Werner Sembach <wse@tuxedocomputers.com>
Cc: All applicable <stable@vger.kernel.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2d2202ba858c112b03f84d546e260c61425831a1 upstream.
cgroup_skb/egress programs which sock_fields test installs process packets
flying in both directions, from the client to the server, and in reverse
direction.
Recently added dst_port check relies on the fact that destination
port (remote peer port) of the socket which sends the packet is known ahead
of time. This holds true only for the client socket, which connects to the
known server port.
Filter out any traffic that is not egressing from the client socket in the
BPF program that tests reading the dst_port.
Fixes: 8f50f16ff39d ("selftests/bpf: Extend verifier and bpf_sock tests for dst_port loads")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220317113920.1068535-3-jakub@cloudflare.com
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8f50f16ff39dd4e2d43d1548ca66925652f8aff7 upstream.
Add coverage to the verifier tests and tests for reading bpf_sock fields to
ensure that 32-bit, 16-bit, and 8-bit loads from dst_port field are allowed
only at intended offsets and produce expected values.
While 16-bit and 8-bit access to dst_port field is straight-forward, 32-bit
wide loads need be allowed and produce a zero-padded 16-bit value for
backward compatibility.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/r/20220130115518.213259-3-jakub@cloudflare.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
[OP: backport to 5.10: adjusted context in sock_fields.c]
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8b3046abc99eefe11438090bcc4ec3a3994b55d0 upstream.
syzbot is reporting lockdep warning at ath9k_wmi_event_tasklet() followed
by kernel panic at get_htc_epid_queue() from ath9k_htc_tx_get_packet() from
ath9k_htc_txstatus() [1], for ath9k_wmi_event_tasklet(WMI_TXSTATUS_EVENTID)
depends on spin_lock_init() from ath9k_init_priv() being already completed.
Since ath9k_wmi_event_tasklet() is set by ath9k_init_wmi() from
ath9k_htc_probe_device(), it is possible that ath9k_wmi_event_tasklet() is
called via tasklet interrupt before spin_lock_init() from ath9k_init_priv()
from ath9k_init_device() from ath9k_htc_probe_device() is called.
Let's hold ath9k_wmi_event_tasklet(WMI_TXSTATUS_EVENTID) no-op until
ath9k_tx_init() completes.
Link: https://syzkaller.appspot.com/bug?extid=31d54c60c5b254d6f75b [1]
Reported-by: syzbot <syzbot+31d54c60c5b254d6f75b@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+31d54c60c5b254d6f75b@syzkaller.appspotmail.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/77b76ac8-2bee-6444-d26c-8c30858b8daa@i-love.sakura.ne.jp
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b0ec7e55fce65f125bd1d7f02e2dc4de62abee34 upstream.
syzbot is reporting lockdep warning followed by kernel panic at
ath9k_htc_rxep() [1], for ath9k_htc_rxep() depends on ath9k_rx_init()
being already completed.
Since ath9k_htc_rxep() is set by ath9k_htc_connect_svc(WMI_BEACON_SVC)
from ath9k_init_htc_services(), it is possible that ath9k_htc_rxep() is
called via timer interrupt before ath9k_rx_init() from ath9k_init_device()
is called.
Since we can't call ath9k_init_device() before ath9k_init_htc_services(),
let's hold ath9k_htc_rxep() no-op until ath9k_rx_init() completes.
Link: https://syzkaller.appspot.com/bug?extid=4d2d56175b934b9a7bf9 [1]
Reported-by: syzbot <syzbot+4d2d56175b934b9a7bf9@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+4d2d56175b934b9a7bf9@syzkaller.appspotmail.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/2b88f416-b2cb-7a18-d688-951e6dc3fe92@i-love.sakura.ne.jp
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b648ab487f31bc4c38941bc770ea97fe394304bb upstream.
The mitigations for RETBleed are currently ineffective on x86_32 since
entry_32.S does not use the required macros. However, for an x86_32
target, the kconfig symbols for them are still enabled by default and
/sys/devices/system/cpu/vulnerabilities/retbleed will wrongly report
that mitigations are in place.
Make all of these symbols depend on X86_64, and only enable RETHUNK by
default on X86_64.
Fixes: f43b9876e857 ("x86/retbleed: Add fine grained Kconfig knobs")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/YtwSR3NNsWp1ohfV@decadent.org.uk
[bwh: Backported to 5.10/5.15/5.18: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b4f894633fa14d7d46ba7676f950b90a401504bb upstream.
sk_lookup doesn't allow setting data_in for bpf_prog_run. This doesn't
play well with the verifier tests, since they always set a 64 byte
input buffer. Allow not running verifier tests by setting
bpf_test.runs to a negative value and don't run the ctx access case
for sk_lookup. We have dedicated ctx access tests so skipping here
doesn't reduce coverage.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210303101816.36774-6-lmb@cloudflare.com
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7c32e8f8bc33a5f4b113a630857e46634e3e143b upstream.
Allow to pass sk_lookup programs to PROG_TEST_RUN. User space
provides the full bpf_sk_lookup struct as context. Since the
context includes a socket pointer that can't be exposed
to user space we define that PROG_TEST_RUN returns the cookie
of the selected socket or zero in place of the socket pointer.
We don't support testing programs that select a reuseport socket,
since this would mean running another (unrelated) BPF program
from the sk_lookup test handler.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210303101816.36774-3-lmb@cloudflare.com
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 607b9cc92bd7208338d714a22b8082fe83bcb177 upstream.
Share the timing / signal interruption logic between different
implementations of PROG_TEST_RUN. There is a change in behaviour
as well. We check the loop exit condition before checking for
pending signals. This resolves an edge case where a signal
arrives during the last iteration. Instead of aborting with
EINTR we return the successful result to user space.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210303101816.36774-2-lmb@cloudflare.com
[dtcccc: fix conflicts in bpf_test_run()]
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d8f4c2d0398fa1d92cacf854daf80d21a46bfefc upstream.
>From the department of "WTAF? How did we miss that!?"...
When we are recovering a buffer, the first thing we do is check the
buffer magic number and extract the LSN from the buffer. If the LSN
is older than the current LSN, we replay the modification to it. If
the metadata on disk is newer than the transaction in the log, we
skip it. This is a fundamental v5 filesystem metadata recovery
behaviour.
generic/482 failed with an attribute writeback failure during log
recovery. The write verifier caught the corruption before it got
written to disk, and the attr buffer dump looked like:
XFS (dm-3): Metadata corruption detected at xfs_attr3_leaf_verify+0x275/0x2e0, xfs_attr3_leaf block 0x19be8
XFS (dm-3): Unmount and run xfs_repair
XFS (dm-3): First 128 bytes of corrupted metadata buffer:
00000000: 00 00 00 00 00 00 00 00 3b ee 00 00 4d 2a 01 e1 ........;...M*..
00000010: 00 00 00 00 00 01 9b e8 00 00 00 01 00 00 05 38 ...............8
^^^^^^^^^^^^^^^^^^^^^^^
00000020: df 39 5e 51 58 ac 44 b6 8d c5 e7 10 44 09 bc 17 .9^QX.D.....D...
00000030: 00 00 00 00 00 02 00 83 00 03 00 cc 0f 24 01 00 .............$..
00000040: 00 68 0e bc 0f c8 00 10 00 00 00 00 00 00 00 00 .h..............
00000050: 00 00 3c 31 0f 24 01 00 00 00 3c 32 0f 88 01 00 ..<1.$....<2....
00000060: 00 00 3c 33 0f d8 01 00 00 00 00 00 00 00 00 00 ..<3............
00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
.....
The highlighted bytes are the LSN that was replayed into the
buffer: 0x100000538. This is cycle 1, block 0x538. Prior to replay,
that block on disk looks like this:
$ sudo xfs_db -c "fsb 0x417d" -c "type attr3" -c p /dev/mapper/thin-vol
hdr.info.hdr.forw = 0
hdr.info.hdr.back = 0
hdr.info.hdr.magic = 0x3bee
hdr.info.crc = 0xb5af0bc6 (correct)
hdr.info.bno = 105448
hdr.info.lsn = 0x100000900
^^^^^^^^^^^
hdr.info.uuid = df395e51-58ac-44b6-8dc5-e7104409bc17
hdr.info.owner = 131203
hdr.count = 2
hdr.usedbytes = 120
hdr.firstused = 3796
hdr.holes = 1
hdr.freemap[0-2] = [base,size]
Note the LSN stamped into the buffer on disk: 1/0x900. The version
on disk is much newer than the log transaction that was being
replayed. That's a bug, and should -never- happen.
So I immediately went to look at xlog_recover_get_buf_lsn() to check
that we handled the LSN correctly. I was wondering if there was a
similar "two commits with the same start LSN skips the second
replay" problem with buffers. I didn't get that far, because I found
a much more basic, rudimentary bug: xlog_recover_get_buf_lsn()
doesn't recognise buffers with XFS_ATTR3_LEAF_MAGIC set in them!!!
IOWs, attr3 leaf buffers fall through the magic number checks
unrecognised, so trigger the "recover immediately" behaviour instead
of undergoing an LSN check. IOWs, we incorrectly replay ATTR3 leaf
buffers and that causes silent on disk corruption of inode attribute
forks and potentially other things....
Git history shows this is *another* zero day bug, this time
introduced in commit 50d5c8d8e9 ("xfs: check LSN ordering for v5
superblocks during recovery") which failed to handle the attr3 leaf
buffers in recovery. And we've failed to handle them ever since...
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 32baa63d82ee3f5ab3bd51bae6bf7d1c15aed8c7 upstream.
When we log an inode, we format the "log inode" core and set an LSN
in that inode core. We do that via xfs_inode_item_format_core(),
which calls:
xfs_inode_to_log_dinode(ip, dic, ip->i_itemp->ili_item.li_lsn);
to format the log inode. It writes the LSN from the inode item into
the log inode, and if recovery decides the inode item needs to be
replayed, it recovers the log inode LSN field and writes it into the
on disk inode LSN field.
Now this might seem like a reasonable thing to do, but it is wrong
on multiple levels. Firstly, if the item is not yet in the AIL,
item->li_lsn is zero. i.e. the first time the inode it is logged and
formatted, the LSN we write into the log inode will be zero. If we
only log it once, recovery will run and can write this zero LSN into
the inode.
This means that the next time the inode is logged and log recovery
runs, it will *always* replay changes to the inode regardless of
whether the inode is newer on disk than the version in the log and
that violates the entire purpose of recording the LSN in the inode
at writeback time (i.e. to stop it going backwards in time on disk
during recovery).
Secondly, if we commit the CIL to the journal so the inode item
moves to the AIL, and then relog the inode, the LSN that gets
stamped into the log inode will be the LSN of the inode's current
location in the AIL, not it's age on disk. And it's not the LSN that
will be associated with the current change. That means when log
recovery replays this inode item, the LSN that ends up on disk is
the LSN for the previous changes in the log, not the current
changes being replayed. IOWs, after recovery the LSN on disk is not
in sync with the LSN of the modifications that were replayed into
the inode. This, again, violates the recovery ordering semantics
that on-disk writeback LSNs provide.
Hence the inode LSN in the log dinode is -always- invalid.
Thirdly, recovery actually has the LSN of the log transaction it is
replaying right at hand - it uses it to determine if it should
replay the inode by comparing it to the on-disk inode's LSN. But it
doesn't use that LSN to stamp the LSN into the inode which will be
written back when the transaction is fully replayed. It uses the one
in the log dinode, which we know is always going to be incorrect.
Looking back at the change history, the inode logging was broken by
commit 93f958f9c4 ("xfs: cull unnecessary icdinode fields") way
back in 2016 by a stupid idiot who thought he knew how this code
worked. i.e. me. That commit replaced an in memory di_lsn field that
was updated only at inode writeback time from the inode item.li_lsn
value - and hence always contained the same LSN that appeared in the
on-disk inode - with a read of the inode item LSN at inode format
time. CLearly these are not the same thing.
Before 93f958f9c4, the log recovery behaviour was irrelevant,
because the LSN in the log inode always matched the on-disk LSN at
the time the inode was logged, hence recovery of the transaction
would never make the on-disk LSN in the inode go backwards or get
out of sync.
A symptom of the problem is this, caught from a failure of
generic/482. Before log recovery, the inode has been allocated but
never used:
xfs_db> inode 393388
xfs_db> p
core.magic = 0x494e
core.mode = 0
....
v3.crc = 0x99126961 (correct)
v3.change_count = 0
v3.lsn = 0
v3.flags2 = 0
v3.cowextsize = 0
v3.crtime.sec = Thu Jan 1 10:00:00 1970
v3.crtime.nsec = 0
After log recovery:
xfs_db> p
core.magic = 0x494e
core.mode = 020444
....
v3.crc = 0x23e68f23 (correct)
v3.change_count = 2
v3.lsn = 0
v3.flags2 = 0
v3.cowextsize = 0
v3.crtime.sec = Thu Jul 22 17:03:03 2021
v3.crtime.nsec = 751000000
...
You can see that the LSN of the on-disk inode is 0, even though it
clearly has been written to disk. I point out this inode, because
the generic/482 failure occurred because several adjacent inodes in
this specific inode cluster were not replayed correctly and still
appeared to be zero on disk when all the other metadata (inobt,
finobt, directories, etc) indicated they should be allocated and
written back.
The fix for this is two-fold. The first is that we need to either
revert the LSN changes in 93f958f9c4 or stop logging the inode LSN
altogether. If we do the former, log recovery does not need to
change but we add 8 bytes of memory per inode to store what is
largely a write-only inode field. If we do the latter, log recovery
needs to stamp the on-disk inode in the same manner that inode
writeback does.
I prefer the latter, because we shouldn't really be trying to log
and replay changes to the on disk LSN as the on-disk value is the
canonical source of the on-disk version of the inode. It also
matches the way we recover buffer items - we create a buf_log_item
that carries the current recovery transaction LSN that gets stamped
into the buffer by the write verifier when it gets written back
when the transaction is fully recovered.
However, this might break log recovery on older kernels even more,
so I'm going to simply ignore the logged value in recovery and stamp
the on-disk inode with the LSN of the transaction being recovered
that will trigger writeback on transaction recovery completion. This
will ensure that the on-disk inode LSN always reflects the LSN of
the last change that was written to disk, regardless of whether it
comes from log recovery or runtime writeback.
Fixes: 93f958f9c4 ("xfs: cull unnecessary icdinode fields")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
