syzbot


KCSAN: data-race in flush_old_exec / mm_update_next_owner (2)

Status: auto-closed as invalid on 2020/06/18 14:03
Subsystems: fs mm
[Documentation on labels]
First crash: 1469d, last: 1466d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in flush_old_exec / mm_update_next_owner fs mm 1 1595d 1595d 0/26 auto-closed as invalid on 2020/02/15 23:36

Sample crash report:
==================================================================
BUG: KCSAN: data-race in flush_old_exec / mm_update_next_owner

write to 0xffff8880a1f0c024 of 4 bytes by task 8767 on cpu 0:
 flush_old_exec fs/exec.c:1297 [inline]
 flush_old_exec+0x640/0xf50 fs/exec.c:1261
 load_elf_binary+0x5e1/0x2c60 fs/binfmt_elf.c:848
 search_binary_handler fs/exec.c:1662 [inline]
 search_binary_handler+0x11c/0x3e0 fs/exec.c:1639
 exec_binprm fs/exec.c:1705 [inline]
 __do_execve_file.isra.0+0xb53/0x1120 fs/exec.c:1825
 do_execveat_common fs/exec.c:1871 [inline]
 do_execve fs/exec.c:1888 [inline]
 __do_sys_execve fs/exec.c:1964 [inline]
 __se_sys_execve fs/exec.c:1959 [inline]
 __x64_sys_execve+0x5e/0x70 fs/exec.c:1959
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880a1f0c024 of 4 bytes by task 8769 on cpu 1:
 mm_update_next_owner+0x376/0x5a0 kernel/exit.c:389
 exit_mm kernel/exit.c:484 [inline]
 do_exit+0x638/0x1880 kernel/exit.c:788
 do_group_exit+0xae/0x1a0 kernel/exit.c:899
 __do_sys_exit_group kernel/exit.c:910 [inline]
 __se_sys_exit_group kernel/exit.c:908 [inline]
 __x64_sys_exit_group+0x2b/0x30 kernel/exit.c:908
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8769 Comm: syz-executor.5 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/04/15 09:12 https://github.com/google/ktsan.git kcsan 40959e34d670 3f3c5574 .config console log report ci2-upstream-kcsan-gce
2020/04/11 20:09 https://github.com/google/ktsan.git kcsan 40959e34d670 a8c6a3f8 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.