110a40dfb7
Before accessing various fields in IPV4 network header
and TCP header, make sure the packet :
- Has IP version 4 (ip->version == 4)
- Has not a silly network length (ip->ihl >= 5)
- Is big enough to hold network and transport headers
- Has not a silly TCP header size (th->doff >= sizeof(struct tcphdr) / 4)
syzbot reported :
BUG: KMSAN: uninit-value in slhc_compress+0x5b9/0x2e60 drivers/net/slip/slhc.c:270
CPU: 0 PID: 11728 Comm: syz-executor231 Not tainted 5.6.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1c9/0x220 lib/dump_stack.c:118
kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
__msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
slhc_compress+0x5b9/0x2e60 drivers/net/slip/slhc.c:270
ppp_send_frame drivers/net/ppp/ppp_generic.c:1637 [inline]
__ppp_xmit_process+0x1902/0x2970 drivers/net/ppp/ppp_generic.c:1495
ppp_xmit_process+0x147/0x2f0 drivers/net/ppp/ppp_generic.c:1516
ppp_write+0x6bb/0x790 drivers/net/ppp/ppp_generic.c:512
do_loop_readv_writev fs/read_write.c:717 [inline]
do_iter_write+0x812/0xdc0 fs/read_write.c:1000
compat_writev+0x2df/0x5a0 fs/read_write.c:1351
do_compat_pwritev64 fs/read_write.c:1400 [inline]
__do_compat_sys_pwritev fs/read_write.c:1420 [inline]
__se_compat_sys_pwritev fs/read_write.c:1414 [inline]
__ia32_compat_sys_pwritev+0x349/0x3f0 fs/read_write.c:1414
do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline]
do_fast_syscall_32+0x3c7/0x6e0 arch/x86/entry/common.c:410
entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f7cd99
Code: 90 e8 0b 00 00 00 f3 90 0f ae e8 eb f9 8d 74 26 00 89 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000ffdb84ac EFLAGS: 00000217 ORIG_RAX: 000000000000014e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000200001c0
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000040047459 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Uninit was created at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:82
slab_alloc_node mm/slub.c:2793 [inline]
__kmalloc_node_track_caller+0xb40/0x1200 mm/slub.c:4401
__kmalloc_reserve net/core/skbuff.c:142 [inline]
__alloc_skb+0x2fd/0xac0 net/core/skbuff.c:210
alloc_skb include/linux/skbuff.h:1051 [inline]
ppp_write+0x115/0x790 drivers/net/ppp/ppp_generic.c:500
do_loop_readv_writev fs/read_write.c:717 [inline]
do_iter_write+0x812/0xdc0 fs/read_write.c:1000
compat_writev+0x2df/0x5a0 fs/read_write.c:1351
do_compat_pwritev64 fs/read_write.c:1400 [inline]
__do_compat_sys_pwritev fs/read_write.c:1420 [inline]
__se_compat_sys_pwritev fs/read_write.c:1414 [inline]
__ia32_compat_sys_pwritev+0x349/0x3f0 fs/read_write.c:1414
do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline]
do_fast_syscall_32+0x3c7/0x6e0 arch/x86/entry/common.c:410
entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.