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KCSAN: data-race in do_sendfile / ksys_write (13)

Status: auto-obsoleted due to no activity on 2023/11/07 08:57
Subsystems: fs
[Documentation on labels]
First crash: 932d, last: 875d
▶ ▼ 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 1d09h 1d09h 0/29 moderation: reported on 2026/02/23 09:50
upstream KCSAN: data-race in do_sendfile / ksys_write (16) fs 6 1 672d 672d 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 1862d 1862d 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 1493d 1517d 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 1453d 1453d 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 982d 995d 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 732d 732d 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 2305d 2305d 0/29 closed as invalid on 2019/11/19 13:24
upstream KCSAN: data-race in do_sendfile / ksys_write (14) fs 6 2 807d 806d 0/29 auto-obsoleted due to no activity on 2024/01/14 07:58
upstream KCSAN: data-race in do_sendfile / ksys_write (2) fs 6 2 2188d 2251d 0/29 auto-closed as invalid on 2020/05/08 04:57
upstream KCSAN: data-race in do_sendfile / ksys_write (6) fs 6 1 1794d 1794d 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 1897d 1897d 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 1312d 1312d 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 1971d 1971d 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 1394d 1397d 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 1245d 1245d 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 0xffff88813749c740 of 8 bytes by task 6227 on cpu 1:
 ksys_write+0x11e/0x1a0 fs/read_write.c:639
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813749c740 of 8 bytes by task 6234 on cpu 0:
 do_sendfile+0x26c/0x9a0 fs/read_write.c:1225
 __do_sys_sendfile64 fs/read_write.c:1316 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0xbd/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000000 -> 0x00000000000000bf

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6234 Comm: syz-executor.1 Not tainted 6.6.0-rc4-syzkaller-00012-gce36c8b14987 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/10/03 08:48 upstream ce36c8b14987 65faba36 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / ksys_write
2023/09/30 11:39 upstream 9f3ebbef746f 8e26a358 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / ksys_write
2023/09/05 21:43 upstream 7733171926cc 0b6286dc .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / ksys_write
2023/08/30 16:53 upstream 6c1b980a7e79 84803932 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / ksys_write
2023/08/07 10:12 upstream 52a93d39b17d 4ffcc9ef .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / ksys_write
* Struck through repros no longer work on HEAD.