66b3025202
commit 9cb7c013420f98fa6fd12fc6a5dc055170c108db upstream.
Reads and Writes to ip6_rt_gc_expire always have been racy,
as syzbot reported lately [1]
There is a possible risk of under-flow, leading
to unexpected high value passed to fib6_run_gc(),
although I have not observed this in the field.
Hosts hitting ip6_dst_gc() very hard are under pretty bad
state anyway.
[1]
BUG: KCSAN: data-race in ip6_dst_gc / ip6_dst_gc
read-write to 0xffff888102110744 of 4 bytes by task 13165 on cpu 1:
ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
dst_alloc+0x9b/0x160 net/core/dst.c:86
ip6_dst_alloc net/ipv6/route.c:344 [inline]
icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
mld_send_cr net/ipv6/mcast.c:2119 [inline]
mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
worker_thread+0x618/0xa70 kernel/workqueue.c:2436
kthread+0x1a9/0x1e0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30
read-write to 0xffff888102110744 of 4 bytes by task 11607 on cpu 0:
ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
dst_alloc+0x9b/0x160 net/core/dst.c:86
ip6_dst_alloc net/ipv6/route.c:344 [inline]
icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
mld_send_cr net/ipv6/mcast.c:2119 [inline]
mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
worker_thread+0x618/0xa70 kernel/workqueue.c:2436
kthread+0x1a9/0x1e0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30
value changed: 0x00000bb3 -> 0x00000ba9
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11607 Comm: kworker/0:21 Not tainted 5.18.0-rc1-syzkaller-00037-g42e7a03d3bad-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: mld mld_ifc_work
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.