syzbot


KCSAN: data-race in __ext4_unlink / __ext4_update_other_inode_time (4)

Status: auto-closed as invalid on 2021/11/16 07:48
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 441d, last: 421d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __ext4_unlink / __ext4_update_other_inode_time 9 697d 730d 0/24 auto-closed as invalid on 2021/02/13 03:24
upstream KCSAN: data-race in __ext4_unlink / __ext4_update_other_inode_time (3) 13 480d 564d 0/24 auto-closed as invalid on 2021/09/18 02:16
upstream KCSAN: data-race in __ext4_unlink / __ext4_update_other_inode_time (2) 2 610d 633d 0/24 auto-closed as invalid on 2021/05/17 11:36

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __ext4_unlink / __ext4_update_other_inode_time

write to 0xffff88813b777350 of 8 bytes by task 1125 on cpu 0:
 __ext4_unlink+0x320/0x4e0 fs/ext4/namei.c:3196
 ext4_unlink+0x1eb/0x340 fs/ext4/namei.c:3231
 vfs_unlink+0x275/0x4b0 fs/namei.c:4102
 do_unlinkat+0x278/0x540 fs/namei.c:4169
 __do_sys_unlink fs/namei.c:4217 [inline]
 __se_sys_unlink fs/namei.c:4215 [inline]
 __x64_sys_unlink+0x2c/0x30 fs/namei.c:4215
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88813b777350 of 8 bytes by task 9609 on cpu 1:
 __ext4_update_other_inode_time+0x141/0x5c0
 ext4_update_other_inodes_time fs/ext4/inode.c:4957 [inline]
 ext4_do_update_inode fs/ext4/inode.c:5091 [inline]
 ext4_mark_iloc_dirty+0x1286/0x1700 fs/ext4/inode.c:5683
 __ext4_mark_inode_dirty+0x4ec/0x5c0 fs/ext4/inode.c:5879
 ext4_dirty_inode+0x86/0xa0 fs/ext4/inode.c:5908
 __mark_inode_dirty+0x77/0x6a0 fs/fs-writeback.c:2398
 mark_inode_dirty include/linux/fs.h:2452 [inline]
 generic_write_end+0x157/0x180 fs/buffer.c:2202
 ext4_da_write_end+0x4cc/0x5e0 fs/ext4/inode.c:3062
 generic_perform_write+0x251/0x3e0 mm/filemap.c:3781
 ext4_buffered_write_iter+0x305/0x400 fs/ext4/file.c:269
 ext4_file_write_iter+0x2e7/0x11f0
 call_write_iter include/linux/fs.h:2163 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x7bc/0x900 fs/read_write.c:594
 ksys_write+0xd9/0x190 fs/read_write.c:647
 __do_sys_write fs/read_write.c:659 [inline]
 __se_sys_write fs/read_write.c:656 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:656
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000161653e23 -> 0x0000000161653e25

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9609 Comm: syz-executor.4 Not tainted 5.15.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (3):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/10/12 07:48 upstream fa5878760579 838e7e2c .config log report info KCSAN: data-race in __ext4_unlink / __ext4_update_other_inode_time
ci2-upstream-kcsan-gce 2021/09/25 01:30 upstream 7d42e9818258 8cac236e .config log report info KCSAN: data-race in __ext4_unlink / __ext4_update_other_inode_time
ci2-upstream-kcsan-gce 2021/09/22 04:32 upstream 92477dd1faa6 169724fe .config log report info KCSAN: data-race in __ext4_unlink / __ext4_update_other_inode_time
* Struck through repros no longer work on HEAD.