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KCSAN: data-race in do_sendfile / ksys_write

Status: closed as invalid on 2019/11/19 13:24
Subsystems: fs
[Documentation on labels]
First crash: 1862d, last: 1862d
Similar bugs (15)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_sendfile / ksys_write (16) fs 1 228d 228d 0/28 auto-obsoleted due to no activity on 2024/05/28 12:59
upstream KCSAN: data-race in do_sendfile / ksys_write (5) fs 1 1419d 1419d 0/28 auto-closed as invalid on 2021/02/23 08:15
upstream KCSAN: data-race in do_sendfile / ksys_write (7) fs 3 1050d 1074d 0/28 auto-closed as invalid on 2022/02/27 04:59
upstream KCSAN: data-race in do_sendfile / ksys_write (8) fs 1 1009d 1009d 0/28 auto-closed as invalid on 2022/04/08 18:00
upstream KCSAN: data-race in do_sendfile / ksys_write (12) fs 2 539d 552d 0/28 auto-obsoleted due to no activity on 2023/07/23 08:25
upstream KCSAN: data-race in do_sendfile / ksys_write (15) fs 1 288d 288d 0/28 auto-obsoleted due to no activity on 2024/03/29 14:30
upstream KCSAN: data-race in do_sendfile / ksys_write (14) fs 2 364d 363d 0/28 auto-obsoleted due to no activity on 2024/01/14 07:58
upstream KCSAN: data-race in do_sendfile / ksys_write (13) fs 5 432d 489d 0/28 auto-obsoleted due to no activity on 2023/11/07 08:57
upstream KCSAN: data-race in do_sendfile / ksys_write (2) fs 2 1745d 1807d 0/28 auto-closed as invalid on 2020/05/08 04:57
upstream KCSAN: data-race in do_sendfile / ksys_write (6) fs 1 1351d 1351d 0/28 auto-closed as invalid on 2021/05/17 10:56
upstream KCSAN: data-race in do_sendfile / ksys_write (4) fs 1 1454d 1454d 0/28 auto-closed as invalid on 2021/01/18 19:47
upstream KCSAN: data-race in do_sendfile / ksys_write (10) fs 1 868d 868d 0/28 auto-closed as invalid on 2022/08/27 13:39
upstream KCSAN: data-race in do_sendfile / ksys_write (3) fs 1 1528d 1528d 0/28 auto-closed as invalid on 2020/11/06 02:13
upstream KCSAN: data-race in do_sendfile / ksys_write (9) fs 2 950d 953d 0/28 auto-closed as invalid on 2022/06/06 18:20
upstream KCSAN: data-race in do_sendfile / ksys_write (11) fs 1 801d 801d 0/28 auto-obsoleted due to no activity on 2022/11/02 18:18

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

write to 0xffff888120e85e68 of 8 bytes by task 25446 on cpu 1:
 ksys_write+0x101/0x1b0 fs/read_write.c:613
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x4c/0x60 fs/read_write.c:620
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888120e85e68 of 8 bytes by task 25459 on cpu 0:
 do_sendfile+0x299/0x7f0 fs/read_write.c:1437
 __do_sys_sendfile64 fs/read_write.c:1519 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0xbe/0x140 fs/read_write.c:1511
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25459 Comm: syz-executor.2 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 25459 Comm: syz-executor.2 Not tainted 5.4.0-rc3+ #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+0xf5/0x159 lib/dump_stack.c:113
 panic+0x210/0x640 kernel/panic.c:221
 kcsan_report.cold+0xc/0x10 kernel/kcsan/report.c:302
 __kcsan_setup_watchpoint+0x32e/0x4a0 kernel/kcsan/core.c:411
 __tsan_read8 kernel/kcsan/kcsan.c:36 [inline]
 __tsan_read8+0x2c/0x30 kernel/kcsan/kcsan.c:36
 do_sendfile+0x299/0x7f0 fs/read_write.c:1437
 __do_sys_sendfile64 fs/read_write.c:1519 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0xbe/0x140 fs/read_write.c:1511
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x459f49
Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ff15a616c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459f49
RDX: 0000000020001000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000ffff R11: 0000000000000246 R12: 00007ff15a6176d4
R13: 00000000004c7c7c R14: 00000000004de068 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/03 06:14 https://github.com/google/ktsan.git kcsan 05f2236801fe d603afc9 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.