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KCSAN: data-race in do_mq_timedreceive / msg_insert (3)

Status: moderation: reported on 2024/06/10 19:40
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+7be8a4c4e396875590b0@syzkaller.appspotmail.com
First crash: 4d22h, last: 4d22h
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_mq_timedreceive / msg_insert kernel 1 997d 997d 0/27 auto-closed as invalid on 2021/10/27 14:36
upstream KCSAN: data-race in do_mq_timedreceive / msg_insert (2) kernel 1 47d 47d 0/27 auto-obsoleted due to no activity on 2024/06/03 00:46

Sample crash report:
ext3: Bad value for 'stripe'
==================================================================
BUG: KCSAN: data-race in do_mq_timedreceive / msg_insert

write to 0xffff88810117d918 of 8 bytes by task 5482 on cpu 0:
 msg_insert+0x10a/0x2e0 ipc/mqueue.c:212
 do_mq_timedsend+0x471/0xa10 ipc/mqueue.c:1161
 __do_sys_mq_timedsend ipc/mqueue.c:1294 [inline]
 __se_sys_mq_timedsend ipc/mqueue.c:1283 [inline]
 __x64_sys_mq_timedsend+0xca/0x150 ipc/mqueue.c:1283
 x64_sys_call+0xd0d/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:243
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810117d918 of 8 bytes by task 5477 on cpu 1:
 do_mq_timedreceive+0x207/0x6e0 ipc/mqueue.c:1230
 __do_sys_mq_timedreceive ipc/mqueue.c:1308 [inline]
 __se_sys_mq_timedreceive ipc/mqueue.c:1297 [inline]
 __x64_sys_mq_timedreceive+0xca/0x150 ipc/mqueue.c:1297
 x64_sys_call+0x2c77/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:244
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888111a26b00 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5477 Comm: syz-executor.3 Not tainted 6.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/10 19:39 upstream 83a7eefedc9b 048c640a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_mq_timedreceive / msg_insert
* Struck through repros no longer work on HEAD.