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KCSAN: data-race in do_sendfile / ksys_write (2)

Status: auto-closed as invalid on 2020/05/08 04:57
Subsystems: fs
[Documentation on labels]
First crash: 2332d, last: 2270d
▶ ▼ Similar bugs (16)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_sendfile / ksys_write (17) fs 6 1 82d 82d 0/29 auto-obsoleted due to no activity on 2026/04/20 09:50
upstream KCSAN: data-race in do_sendfile / ksys_write (16) fs 6 1 753d 753d 0/29 auto-obsoleted due to no activity on 2024/05/28 12:59
upstream KCSAN: data-race in do_sendfile / ksys_write (5) fs 6 1 1944d 1944d 0/29 auto-closed as invalid on 2021/02/23 08:15
upstream KCSAN: data-race in do_sendfile / ksys_write (7) fs 6 3 1575d 1599d 0/29 auto-closed as invalid on 2022/02/27 04:59
upstream KCSAN: data-race in do_sendfile / ksys_write (8) fs 6 1 1534d 1534d 0/29 auto-closed as invalid on 2022/04/08 18:00
upstream KCSAN: data-race in do_sendfile / ksys_write (12) fs 6 2 1063d 1077d 0/29 auto-obsoleted due to no activity on 2023/07/23 08:25
upstream KCSAN: data-race in do_sendfile / ksys_write (15) fs 6 1 813d 813d 0/29 auto-obsoleted due to no activity on 2024/03/29 14:30
upstream KCSAN: data-race in do_sendfile / ksys_write fs 6 1 2387d 2387d 0/29 closed as invalid on 2019/11/19 13:24
upstream KCSAN: data-race in do_sendfile / ksys_write (14) fs 6 2 889d 888d 0/29 auto-obsoleted due to no activity on 2024/01/14 07:58
upstream KCSAN: data-race in do_sendfile / ksys_write (13) fs 6 5 956d 1013d 0/29 auto-obsoleted due to no activity on 2023/11/07 08:57
upstream KCSAN: data-race in do_sendfile / ksys_write (6) fs 6 1 1876d 1876d 0/29 auto-closed as invalid on 2021/05/17 10:56
upstream KCSAN: data-race in do_sendfile / ksys_write (4) fs 6 1 1979d 1979d 0/29 auto-closed as invalid on 2021/01/18 19:47
upstream KCSAN: data-race in do_sendfile / ksys_write (10) fs 6 1 1393d 1393d 0/29 auto-closed as invalid on 2022/08/27 13:39
upstream KCSAN: data-race in do_sendfile / ksys_write (3) fs 6 1 2053d 2053d 0/29 auto-closed as invalid on 2020/11/06 02:13
upstream KCSAN: data-race in do_sendfile / ksys_write (9) fs 6 2 1475d 1478d 0/29 auto-closed as invalid on 2022/06/06 18:20
upstream KCSAN: data-race in do_sendfile / ksys_write (11) fs 6 1 1326d 1326d 0/29 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 0xffff88811dcc8168 of 8 bytes by task 30281 on cpu 0:
 ksys_write+0xf0/0x1a0 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+0x49/0x60 fs/read_write.c:620
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88811dcc8168 of 8 bytes by task 30285 on cpu 1:
 do_sendfile+0x29a/0x810 fs/read_write.c:1493
 __do_sys_sendfile64 fs/read_write.c:1575 [inline]
 __se_sys_sendfile64 fs/read_write.c:1567 [inline]
 __x64_sys_sendfile64+0xb8/0x140 fs/read_write.c:1567
 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: 30285 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
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 30285 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
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x11d/0x187 lib/dump_stack.c:118
 panic+0x210/0x640 kernel/panic.c:221
 kcsan_report.cold+0xc/0x14 kernel/kcsan/report.c:556
 kcsan_setup_watchpoint+0x304/0x400 kernel/kcsan/core.c:495
 do_sendfile+0x29a/0x810 fs/read_write.c:1493
 __do_sys_sendfile64 fs/read_write.c:1575 [inline]
 __se_sys_sendfile64 fs/read_write.c:1567 [inline]
 __x64_sys_sendfile64+0xb8/0x140 fs/read_write.c:1567
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c479
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:00007fcd7e276c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fcd7e2776d4 RCX: 000000000045c479
RDX: 0000000020001000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 000000000076bfc0 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000ffff R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000008d1 R14: 00000000004cb364 R15: 000000000076bfcc
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/02/28 04:48 https://github.com/google/ktsan.git kcsan 766d004d1b85 c88c7b75 .config console log report ci2-upstream-kcsan-gce
2019/12/27 18:01 https://github.com/google/ktsan.git kcsan 245a43005292 be5c2c81 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.