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KCSAN: data-race in ext4_file_write_iter / ext4_setattr (7)

Status: auto-closed as invalid on 2022/03/09 13:22
Subsystems: ext4
[Documentation on labels]
First crash: 814d, last: 814d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_file_write_iter / ext4_setattr (2) ext4 1 1236d 1236d 0/26 auto-closed as invalid on 2021/01/11 11:39
upstream KCSAN: data-race in ext4_file_write_iter / ext4_setattr (3) ext4 2 1113d 1114d 0/26 auto-closed as invalid on 2021/05/14 00:08
upstream KCSAN: data-race in ext4_file_write_iter / ext4_setattr (4) ext4 1 1078d 1078d 0/26 auto-closed as invalid on 2021/06/18 10:04
upstream KCSAN: data-race in ext4_file_write_iter / ext4_setattr ext4 3 1305d 1329d 0/26 auto-closed as invalid on 2020/11/03 10:53
upstream KCSAN: data-race in ext4_file_write_iter / ext4_setattr (5) ext4 3 986d 1023d 0/26 auto-closed as invalid on 2021/09/18 07:46
upstream KCSAN: data-race in ext4_file_write_iter / ext4_setattr (6) ext4 8 892d 943d 0/26 auto-closed as invalid on 2021/12/21 17:24

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_file_write_iter / ext4_setattr

write to 0xffff888106290658 of 8 bytes by task 25457 on cpu 1:
 i_size_write include/linux/fs.h:907 [inline]
 ext4_setattr+0xd6b/0xf00 fs/ext4/inode.c:5435
 notify_change+0x924/0xbf0 fs/attr.c:410
 do_truncate+0xf7/0x140 fs/open.c:65
 handle_truncate fs/namei.c:3132 [inline]
 do_open fs/namei.c:3480 [inline]
 path_openat+0x1873/0x1f30 fs/namei.c:3609
 do_filp_open+0x105/0x220 fs/namei.c:3636
 do_sys_openat2+0xb5/0x2b0 fs/open.c:1214
 do_sys_open fs/open.c:1230 [inline]
 __do_sys_creat fs/open.c:1306 [inline]
 __se_sys_creat fs/open.c:1300 [inline]
 __x64_sys_creat+0x62/0x80 fs/open.c:1300
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888106290658 of 8 bytes by task 25452 on cpu 0:
 i_size_read include/linux/fs.h:885 [inline]
 ext4_dio_write_iter fs/ext4/file.c:493 [inline]
 ext4_file_write_iter+0x14b/0x11f0 fs/ext4/file.c:675
 call_write_iter include/linux/fs.h:2074 [inline]
 do_iter_readv_writev+0x2de/0x380 fs/read_write.c:725
 do_iter_write+0x192/0x5c0 fs/read_write.c:851
 vfs_iter_write+0x4c/0x70 fs/read_write.c:892
 iter_file_splice_write+0x43a/0x790 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000000f0000 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25452 Comm: syz-executor.2 Not tainted 5.17.0-rc2-syzkaller-00039-g9f7fb8de5d9b #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
2022/02/02 13:18 upstream 9f7fb8de5d9b 4ebb2798 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_file_write_iter / ext4_setattr
* Struck through repros no longer work on HEAD.