==================================================================
BUG: KCSAN: data-race in userfaultfd_ioctl / userfaultfd_ioctl
write to 0xffff888124beeff0 of 4 bytes by task 16432 on cpu 0:
userfaultfd_api fs/userfaultfd.c:1868 [inline]
userfaultfd_ioctl+0x718/0x2530 fs/userfaultfd.c:1892
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739
__x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
read to 0xffff888124beeff0 of 4 bytes by task 16440 on cpu 1:
userfaultfd_ioctl+0x8f/0x2530 fs/userfaultfd.c:1887
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739
__x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16440 Comm: syz-executor.1 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 16440 Comm: syz-executor.1 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x10f/0x19d lib/dump_stack.c:118
panic+0x207/0x64a kernel/panic.c:231
kcsan_report+0x684/0x690 kernel/kcsan/report.c:630
kcsan_setup_watchpoint+0x41e/0x4a0 kernel/kcsan/core.c:540
userfaultfd_ioctl+0x8f/0x2530 fs/userfaultfd.c:1887
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739
__x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d5b9
Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f02954a4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000001a380 RCX: 000000000045d5b9
RDX: 00000000200000c0 RSI: 00000000c020aa00 RDI: 0000000000000003
RBP: 000000000118d020 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cfec
R13: 00007ffddce6439f R14: 00007f02954a59c0 R15: 000000000118cfec
Kernel Offset: disabled
Rebooting in 86400 seconds..