KCSAN: data-race in ext4_ext_insert_extent / ext4_mark_iloc_dirty

Status: closed as invalid on 2020/06/18 14:24
Subsystems: ext4
[Documentation on labels]
First crash: 2480d, last: 2274d
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_ext_insert_extent / ext4_mark_iloc_dirty (2) ext4 6 99 2011d 2116d 0/29 auto-closed as invalid on 2021/03/12 13:10
upstream KCSAN: data-race in ext4_ext_insert_extent / ext4_mark_iloc_dirty (3) ext4 6 60 1736d 1801d 0/29 auto-closed as invalid on 2021/12/12 11:00

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_ext_insert_extent / ext4_mark_iloc_dirty

write to 0xffff8880b690b998 of 4 bytes by task 20275 on cpu 0:
 ext4_ext_insert_extent+0x8c9/0x25f0 fs/ext4/extents.c:2105
 ext4_ext_map_blocks+0xbd1/0x1fb0 fs/ext4/extents.c:4238
 ext4_map_blocks+0x230/0xcf0 fs/ext4/inode.c:621
 mpage_map_one_extent fs/ext4/inode.c:2364 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2417 [inline]
 ext4_writepages+0x10c4/0x1e10 fs/ext4/inode.c:2770
 do_writepages+0x6b/0x170 mm/page-writeback.c:2344
 __filemap_fdatawrite_range+0x1bb/0x220 mm/filemap.c:421
 file_write_and_wait_range+0xfb/0x160 mm/filemap.c:760
 ext4_sync_file+0x26e/0x8b0 fs/ext4/fsync.c:153
 vfs_fsync_range+0x7c/0x150 fs/sync.c:197
 generic_write_sync include/linux/fs.h:2872 [inline]
 ext4_buffered_write_iter+0x211/0x280 fs/ext4/file.c:277
 ext4_file_write_iter+0xf4/0xd30 fs/ext4/file.c:642
 call_write_iter include/linux/fs.h:1907 [inline]
 do_iter_readv_writev+0x4a7/0x5d0 fs/read_write.c:694
 do_iter_write fs/read_write.c:999 [inline]
 do_iter_write+0x137/0x3a0 fs/read_write.c:980
 vfs_iter_write+0x56/0x80 fs/read_write.c:1040
 iter_file_splice_write+0x530/0x830 fs/splice.c:760
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x97/0xb0 fs/splice.c:1037
 splice_direct_to_actor+0x22f/0x540 fs/splice.c:992
 do_splice_direct+0x152/0x1d0 fs/splice.c:1080
 do_sendfile+0x380/0x800 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0x121/0x140 fs/read_write.c:1568
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880b690b998 of 4 bytes by task 20270 on cpu 1:
 ext4_do_update_inode fs/ext4/inode.c:5023 [inline]
 ext4_mark_iloc_dirty+0xa37/0x1580 fs/ext4/inode.c:5603
 ext4_mark_inode_dirty+0xe6/0x420 fs/ext4/inode.c:5796
 ext4_dirty_inode+0xad/0xd0 fs/ext4/inode.c:5827
 __mark_inode_dirty+0x5b7/0x940 fs/fs-writeback.c:2258
 mark_inode_dirty include/linux/fs.h:2189 [inline]
 generic_write_end+0x24c/0x290 fs/buffer.c:2193
 ext4_da_write_end+0x162/0x690 fs/ext4/inode.c:3090
 generic_perform_write+0x1d7/0x320 mm/filemap.c:3313
 ext4_buffered_write_iter+0x14e/0x280 fs/ext4/file.c:270
 ext4_file_write_iter+0xf4/0xd30 fs/ext4/file.c:642
 call_write_iter include/linux/fs.h:1907 [inline]
 do_iter_readv_writev+0x4a7/0x5d0 fs/read_write.c:694
 do_iter_write fs/read_write.c:999 [inline]
 do_iter_write+0x137/0x3a0 fs/read_write.c:980
 vfs_iter_write+0x56/0x80 fs/read_write.c:1040
 iter_file_splice_write+0x530/0x830 fs/splice.c:760
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x97/0xb0 fs/splice.c:1037
 splice_direct_to_actor+0x22f/0x540 fs/splice.c:992
 do_splice_direct+0x152/0x1d0 fs/splice.c:1080
 do_sendfile+0x380/0x800 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0x121/0x140 fs/read_write.c:1568
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 20270 Comm: syz-executor.3 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/19 04:10 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 684d3606 .config console log report ci2-upstream-kcsan-gce
2020/05/09 05:22 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 e97b06d3 .config console log report ci2-upstream-kcsan-gce
2020/04/13 00:17 https://github.com/google/ktsan.git kcsan 40959e34d670 17a986e5 .config console log report ci2-upstream-kcsan-gce
2020/03/24 00:40 https://github.com/google/ktsan.git kcsan 40959e34d670 84f999d6 .config console log report ci2-upstream-kcsan-gce
2020/02/20 00:20 https://github.com/google/ktsan.git kcsan b12d66a6c34f 47fae6e9 .config console log report ci2-upstream-kcsan-gce
2020/02/01 16:36 https://github.com/google/ktsan.git kcsan 245a43005292 326d4c78 .config console log report ci2-upstream-kcsan-gce
2020/01/31 19:32 https://github.com/google/ktsan.git kcsan 245a43005292 0eb59c27 .config console log report ci2-upstream-kcsan-gce
2020/01/06 04:18 https://github.com/google/ktsan.git kcsan 245a43005292 438e1227 .config console log report ci2-upstream-kcsan-gce
2019/12/30 17:13 https://github.com/google/ktsan.git kcsan 245a43005292 6b36d338 .config console log report ci2-upstream-kcsan-gce
2019/12/11 21:33 https://github.com/google/ktsan.git kcsan ef798c30ba4e 0d368675 .config console log report ci2-upstream-kcsan-gce
2019/12/07 19:38 https://github.com/google/ktsan.git kcsan ef798c30ba4e 1508f453 .config console log report ci2-upstream-kcsan-gce
2019/12/06 02:08 https://github.com/google/ktsan.git kcsan ef798c30ba4e 98b4ef2d .config console log report ci2-upstream-kcsan-gce
2019/12/03 04:03 https://github.com/google/ktsan.git kcsan ef798c30ba4e ab342da3 .config console log report ci2-upstream-kcsan-gce
2019/11/29 22:37 https://github.com/google/ktsan.git kcsan ef798c30ba4e 4f7e1d0f .config console log report ci2-upstream-kcsan-gce
2019/11/28 06:22 https://github.com/google/ktsan.git kcsan ef798c30ba4e 0d63f89c .config console log report ci2-upstream-kcsan-gce
2019/11/16 06:07 https://github.com/google/ktsan.git kcsan 5863cc791e4c cdac920b .config console log report ci2-upstream-kcsan-gce
2019/10/26 12:34 https://github.com/google/ktsan.git kcsan 05f2236801fe 25bb509e .config console log report ci2-upstream-kcsan-gce
2019/10/25 13:37 https://github.com/google/ktsan.git kcsan 05f2236801fe 04ca72cd .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.