diff options
| author | Schspa Shi <schspa@gmail.com> | 2022-11-16 19:45:11 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-11-18 12:14:55 +0000 |
| commit | ab0377803dafc58f1e22296708c1c28e309414d6 (patch) | |
| tree | 5601c8970cfa5eae40892611a133acb88a5655f9 /include/net/mrp.h | |
| parent | 8cf4f8c7d99addb6c2c2273fac7c20ca7c50db45 (diff) | |
mrp: introduce active flags to prevent UAF when applicant uninit
The caller of del_timer_sync must prevent restarting of the timer, If
we have no this synchronization, there is a small probability that the
cancellation will not be successful.
And syzbot report the fellowing crash:
==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:929 [inline]
BUG: KASAN: use-after-free in enqueue_timer+0x18/0xa4 kernel/time/timer.c:605
Write at addr f9ff000024df6058 by task syz-fuzzer/2256
Pointer tag: [f9], memory tag: [fe]
CPU: 1 PID: 2256 Comm: syz-fuzzer Not tainted 6.1.0-rc5-syzkaller-00008-
ge01d50cbd6ee #0
Hardware name: linux,dummy-virt (DT)
Call trace:
dump_backtrace.part.0+0xe0/0xf0 arch/arm64/kernel/stacktrace.c:156
dump_backtrace arch/arm64/kernel/stacktrace.c:162 [inline]
show_stack+0x18/0x40 arch/arm64/kernel/stacktrace.c:163
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x68/0x84 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:284 [inline]
print_report+0x1a8/0x4a0 mm/kasan/report.c:395
kasan_report+0x94/0xb4 mm/kasan/report.c:495
__do_kernel_fault+0x164/0x1e0 arch/arm64/mm/fault.c:320
do_bad_area arch/arm64/mm/fault.c:473 [inline]
do_tag_check_fault+0x78/0x8c arch/arm64/mm/fault.c:749
do_mem_abort+0x44/0x94 arch/arm64/mm/fault.c:825
el1_abort+0x40/0x60 arch/arm64/kernel/entry-common.c:367
el1h_64_sync_handler+0xd8/0xe4 arch/arm64/kernel/entry-common.c:427
el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:576
hlist_add_head include/linux/list.h:929 [inline]
enqueue_timer+0x18/0xa4 kernel/time/timer.c:605
mod_timer+0x14/0x20 kernel/time/timer.c:1161
mrp_periodic_timer_arm net/802/mrp.c:614 [inline]
mrp_periodic_timer+0xa0/0xc0 net/802/mrp.c:627
call_timer_fn.constprop.0+0x24/0x80 kernel/time/timer.c:1474
expire_timers+0x98/0xc4 kernel/time/timer.c:1519
To fix it, we can introduce a new active flags to make sure the timer will
not restart.
Reported-by: syzbot+6fd64001c20aa99e34a4@syzkaller.appspotmail.com
Signed-off-by: Schspa Shi <schspa@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/mrp.h')
| -rw-r--r-- | include/net/mrp.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/net/mrp.h b/include/net/mrp.h index 92cd3fb6cf9d..b28915ffea28 100644 --- a/include/net/mrp.h +++ b/include/net/mrp.h @@ -124,6 +124,7 @@ struct mrp_applicant { struct sk_buff *pdu; struct rb_root mad; struct rcu_head rcu; + bool active; }; struct mrp_port { |