Hello,
syzbot found the following crash on:
HEAD commit: 7cc2a8ea Merge tag 'block-5.8-2020-07-01' of git://git.ker..
git tree: upstream
console output:
https://syzkaller.appspot.com/x/log.txt?x=15363ccb100000
kernel config:
https://syzkaller.appspot.com/x/.config?x=ef2c2e4f6006998c
dashboard link:
https://syzkaller.appspot.com/bug?extid=ba0342a3c9409763fa94
compiler: clang version 11.0.0 (
https://github.com/llvm/llvm-project.git ca2dcbd030eadbf0aa9b660efe864ff08af6e18b)
CC: [
chri...@brauner.io ebie...@xmission.com linux-...@vger.kernel.org ol...@redhat.com]
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by:
syzbot+ba0342...@syzkaller.appspotmail.com
==================================================================
BUG: KCSAN: data-race in do_signal_stop / do_signal_stop
write to 0xffff888097178024 of 4 bytes by task 25965 on cpu 1:
freezer_count include/linux/freezer.h:121 [inline]
freezable_schedule include/linux/freezer.h:173 [inline]
do_signal_stop+0x562/0x6d0 kernel/signal.c:2395
get_signal+0xb9a/0x1650 kernel/signal.c:2601
do_signal+0x25/0x270 arch/x86/kernel/signal.c:810
exit_to_usermode_loop arch/x86/entry/common.c:212 [inline]
__prepare_exit_to_usermode+0x127/0x230 arch/x86/entry/common.c:246
__syscall_return_slowpath+0x47/0x60 arch/x86/entry/common.c:329
do_syscall_64+0x5d/0xb0 arch/x86/entry/common.c:368
entry_SYSCALL_64_after_hwframe+0x44/0xa9
read to 0xffff888097178024 of 4 bytes by task 25915 on cpu 0:
task_set_jobctl_pending kernel/signal.c:291 [inline]
do_signal_stop+0x32e/0x6d0 kernel/signal.c:2354
get_signal+0x10c8/0x1650 kernel/signal.c:2703
do_signal+0x25/0x270 arch/x86/kernel/signal.c:810
exit_to_usermode_loop arch/x86/entry/common.c:212 [inline]
__prepare_exit_to_usermode+0x127/0x230 arch/x86/entry/common.c:246
prepare_exit_to_usermode+0x5/0x20 arch/x86/entry/common.c:277
idtentry_exit_cond_rcu+0xe/0x30 arch/x86/entry/common.c:649
asm_sysvec_reschedule_ipi+0x12/0x20 arch/x86/include/asm/idtentry.h:601
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25915 Comm: syz-executor.4 Not tainted 5.8.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
---
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