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KCSAN: data-race in do_sendfile / do_sendfile (10)

Status: moderation: reported on 2024/11/13 18:24
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+be39254b0cdfa55a2579@syzkaller.appspotmail.com
First crash: 265d, last: 3d23h
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_sendfile / do_sendfile (3) fs 6 1 942d 942d 0/29 auto-obsoleted due to no activity on 2023/03/17 22:50
upstream KCSAN: data-race in do_sendfile / do_sendfile (4) fs 6 4 830d 853d 0/29 auto-obsoleted due to no activity on 2023/06/02 10:13
upstream KCSAN: data-race in do_sendfile / do_sendfile fs 6 2 1265d 1280d 0/29 auto-closed as invalid on 2022/03/24 16:27
upstream KCSAN: data-race in do_sendfile / do_sendfile (9) fs 6 1 324d 324d 0/29 auto-obsoleted due to no activity on 2024/10/20 07:46
upstream KCSAN: data-race in do_sendfile / do_sendfile (7) fs 6 5 555d 604d 0/29 auto-obsoleted due to no activity on 2024/03/03 18:17
upstream KCSAN: data-race in do_sendfile / do_sendfile (6) fs 6 1 700d 700d 0/29 auto-obsoleted due to no activity on 2023/10/10 12:26
upstream KCSAN: data-race in do_sendfile / do_sendfile (5) fs 6 3 741d 762d 0/29 auto-obsoleted due to no activity on 2023/08/30 17:21
upstream KCSAN: data-race in do_sendfile / do_sendfile (8) fs 6 2 380d 404d 0/29 auto-obsoleted due to no activity on 2024/08/25 22:44
upstream KCSAN: data-race in do_sendfile / do_sendfile (2) fs 6 1 1081d 1081d 0/29 auto-closed as invalid on 2022/09/24 23:59

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

write to 0xffff88810461e430 of 8 bytes by task 13166 on cpu 1:
 do_sendfile+0x408/0x650 fs/read_write.c:1384
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64 fs/read_write.c:1417 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1417
 x64_sys_call+0x2bb0/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff88810461e430 of 8 bytes by task 13162 on cpu 0:
 do_sendfile+0x408/0x650 fs/read_write.c:1384
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64 fs/read_write.c:1417 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1417
 x64_sys_call+0x2bb0/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000004 -> 0x00000000000003b0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 13162 Comm: syz.1.1940 Not tainted 6.16.0-syzkaller-10910-g0905809b38bd #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
==================================================================

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/02 04:35 upstream 0905809b38bd 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2025/07/18 07:39 upstream 6832a9317eee 88248e14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2025/07/10 00:01 upstream 8c2e52ebbe88 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2025/07/02 03:25 upstream 66701750d556 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2025/05/29 08:13 upstream 90b83efa6701 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2025/05/01 02:10 upstream 7a13c14ee59d ce7952f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2025/03/23 21:55 upstream 586de92313fc 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2025/02/15 15:34 upstream 78a632a2086c 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2025/01/22 09:35 upstream c4b9570cfb63 da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2024/12/30 00:15 upstream 4099a71718b0 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2024/12/26 15:04 upstream 9b2ffa6148b1 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2024/12/19 23:41 upstream baaa2567a712 5905cb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2024/12/02 22:44 upstream e70140ba0d2b b499ea68 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2024/11/25 16:27 upstream 9f16d5e6f220 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sendfile / do_sendfile
2024/11/13 18:24 upstream f1b785f4c787 bb3f8425 .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.