Schspa Shi 755eb08792 mrp: introduce active flags to prevent UAF when applicant uninit ... [ Upstream commit ab0377803d ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-01-14 10:16:18 +01:00
..
fc.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
fddi.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
garp.c	net/802/garp: fix memleak in garp_request_join()	2021-07-31 08:16:11 +02:00
hippi.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mrp.c	mrp: introduce active flags to prevent UAF when applicant uninit	2023-01-14 10:16:18 +01:00
p8022.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
p8023.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
psnap.c	net: 802: psnap.c: Use built-in RCU list checking	2020-02-24 13:02:53 -08:00
stp.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00