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KCSAN: data-race in do_splice / pipe_read

Status: auto-closed as invalid on 2022/07/16 23:41
Subsystems: fs
[Documentation on labels]
First crash: 674d, last: 674d

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

write to 0xffff88814b230654 of 4 bytes by task 5764 on cpu 1:
 pipe_read+0x393/0x890 fs/pipe.c:331
 call_read_iter include/linux/fs.h:2052 [inline]
 new_sync_read fs/read_write.c:401 [inline]
 vfs_read+0x5a5/0x6a0 fs/read_write.c:482
 ksys_read+0xe8/0x1a0 fs/read_write.c:620
 __do_sys_read fs/read_write.c:630 [inline]
 __se_sys_read fs/read_write.c:628 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:628
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

read to 0xffff88814b230654 of 4 bytes by task 5745 on cpu 0:
 ipipe_prep fs/splice.c:1371 [inline]
 splice_pipe_to_pipe fs/splice.c:1450 [inline]
 do_splice+0x1d2/0xd90 fs/splice.c:1054
 __do_splice fs/splice.c:1144 [inline]
 __do_sys_splice fs/splice.c:1350 [inline]
 __se_sys_splice+0x2a4/0x380 fs/splice.c:1332
 __x64_sys_splice+0x74/0x80 fs/splice.c:1332
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

value changed: 0x00000008 -> 0x00000010

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5745 Comm: syz-executor.3 Not tainted 5.19.0-rc1-syzkaller-00262-g0885eacdc81f-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/06/11 23:36 upstream 0885eacdc81f 0d5abf15 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_splice / pipe_read
* Struck through repros no longer work on HEAD.