Hello,
syzbot found the following crash on:
HEAD commit: 35e884f8 Merge tag 'for-linus-5.8b-rc4-tag' of git://git.k..
git tree: upstream
console output:
https://syzkaller.appspot.com/x/log.txt?x=136787e5100000
kernel config:
https://syzkaller.appspot.com/x/.config?x=ef2c2e4f6006998c
dashboard link:
https://syzkaller.appspot.com/bug?extid=dfcff47717996ec0ac40
compiler: clang version 11.0.0 (
https://github.com/llvm/llvm-project.git ca2dcbd030eadbf0aa9b660efe864ff08af6e18b)
CC: [
chri...@brauner.io ebie...@xmission.com ja...@google.com linux-...@vger.kernel.org mi...@kernel.org ol...@redhat.com pet...@infradead.org tg...@linutronix.de]
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+dfcff4...@syzkaller.appspotmail.com
==================================================================
BUG: KCSAN: data-race in exit_mm / mm_update_next_owner
write to 0xffff8880b2ba5428 of 8 bytes by task 16835 on cpu 0:
exit_mm+0x292/0x330 kernel/exit.c:477
do_exit+0x415/0x16e0 kernel/exit.c:792
do_group_exit+0xcb/0x180 kernel/exit.c:903
get_signal+0x106d/0x1650 kernel/signal.c:2743
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 0xffff8880b2ba5428 of 8 bytes by task 16830 on cpu 1:
mm_update_next_owner+0x233/0x4a0 kernel/exit.c:389
exit_mm+0x2c0/0x330 kernel/exit.c:481
do_exit+0x415/0x16e0 kernel/exit.c:792
do_group_exit+0x17a/0x180 kernel/exit.c:903
__do_sys_exit_group+0xb/0x10 kernel/exit.c:914
__se_sys_exit_group+0x5/0x10 kernel/exit.c:912
__x64_sys_exit_group+0x16/0x20 kernel/exit.c:912
do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:359
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16830 Comm: syz-executor.3 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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