syzbot


KCSAN: data-race in do_sendfile / do_sendfile (7)

Status: moderation: reported on 2023/12/11 00:05
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+6a6c4c031c65cb4a0704@syzkaller.appspotmail.com
First crash: 118d, last: 32d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_sendfile / do_sendfile (3) fs 1 419d 419d 0/26 auto-obsoleted due to no activity on 2023/03/17 22:50
upstream KCSAN: data-race in do_sendfile / do_sendfile (4) fs 4 307d 330d 0/26 auto-obsoleted due to no activity on 2023/06/02 10:13
upstream KCSAN: data-race in do_sendfile / do_sendfile fs 2 742d 757d 0/26 auto-closed as invalid on 2022/03/24 16:27
upstream KCSAN: data-race in do_sendfile / do_sendfile (6) fs 1 177d 177d 0/26 auto-obsoleted due to no activity on 2023/10/10 12:26
upstream KCSAN: data-race in do_sendfile / do_sendfile (5) fs 3 218d 239d 0/26 auto-obsoleted due to no activity on 2023/08/30 17:21
upstream KCSAN: data-race in do_sendfile / do_sendfile (2) fs 1 558d 558d 0/26 auto-closed as invalid on 2022/09/24 23:59

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

write to 0xffff888151f82e40 of 8 bytes by task 4326 on cpu 1:
 do_sendfile+0x758/0x960 fs/read_write.c:1309
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

write to 0xffff888151f82e40 of 8 bytes by task 4328 on cpu 0:
 do_sendfile+0x758/0x960 fs/read_write.c:1309
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000000 -> 0x0000000000208200

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4328 Comm: syz-executor.4 Not tainted 6.8.0-rc1-syzkaller-00356-g8a696a29c690 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/28 18:17 upstream 8a696a29c690 cc4a4020 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2023/12/30 22:59 upstream 453f5db0619e fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2023/12/13 15:46 upstream 88035e5694a8 ebcad15c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2023/12/11 20:32 upstream a39b6ac3781d 28b24332 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2023/11/03 13:15 upstream 8f6f76a6a29f c4ac074c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
* Struck through repros no longer work on HEAD.