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KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (4)

Status: auto-closed as invalid on 2021/06/26 18:17
Subsystems: ext4
[Documentation on labels]
First crash: 1045d, last: 1040d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (2) ext4 2 1176d 1183d 0/26 auto-closed as invalid on 2021/02/11 08:14
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (6) ext4 1 848d 848d 0/26 auto-closed as invalid on 2022/01/05 07:12
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (3) ext4 1 1081d 1081d 0/26 auto-closed as invalid on 2021/05/17 10:01
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (5) ext4 4 953d 999d 0/26 auto-closed as invalid on 2021/09/22 04:33
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent ext4 1 1232d 1207d 0/26 auto-closed as invalid on 2020/12/21 12:00

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent

write to 0xffff888106a1e578 of 8 bytes by task 7513 on cpu 1:
 __es_find_extent_range+0x28e/0x330 fs/ext4/extents_status.c:298
 ext4_es_find_extent_range+0x87/0x190 fs/ext4/extents_status.c:320
 ext4_ext_put_gap_in_cache fs/ext4/extents.c:2237 [inline]
 ext4_ext_map_blocks+0xf19/0x1f00 fs/ext4/extents.c:4143
 ext4_da_map_blocks fs/ext4/inode.c:1757 [inline]
 ext4_da_get_block_prep+0x428/0x9b0 fs/ext4/inode.c:1834
 __block_write_begin_int+0x4a2/0x1060 fs/buffer.c:2031
 __block_write_begin+0x2b/0x40 fs/buffer.c:2081
 ext4_da_write_begin+0x4c8/0x820 fs/ext4/inode.c:3018
 generic_perform_write+0x196/0x3a0 mm/filemap.c:3660
 ext4_buffered_write_iter+0x2f2/0x3f0 fs/ext4/file.c:269
 ext4_file_write_iter+0x2e7/0x11d0 fs/ext4/file.c:519
 call_write_iter include/linux/fs.h:2114 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 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+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888106a1e578 of 8 bytes by task 7544 on cpu 0:
 ext4_es_lookup_extent+0xad/0x490 fs/ext4/extents_status.c:937
 ext4_map_blocks+0xfd/0xef0 fs/ext4/inode.c:530
 ext4_mpage_readpages+0x6d9/0x1130 fs/ext4/readpage.c:304
 ext4_readahead+0x99/0xa0 fs/ext4/inode.c:3260
 read_pages+0x9f/0x530 mm/readahead.c:130
 page_cache_ra_unbounded+0x3c8/0x410 mm/readahead.c:238
 ondemand_readahead+0x579/0x7b0 mm/readahead.c:267
 page_cache_async_ra+0x165/0x190 mm/readahead.c:607
 page_cache_async_readahead include/linux/pagemap.h:902 [inline]
 filemap_readahead mm/filemap.c:2442 [inline]
 filemap_get_pages mm/filemap.c:2483 [inline]
 filemap_read+0x49d/0x1230 mm/filemap.c:2550
 generic_file_read_iter+0x75/0x2c0 mm/filemap.c:2701
 ext4_file_read_iter+0x1db/0x290 fs/ext4/file.c:73
 call_read_iter include/linux/fs.h:2108 [inline]
 generic_file_splice_read+0x22a/0x310 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7544 Comm: syz-executor.5 Not tainted 5.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/05/22 18:08 upstream 45af60e7ced0 3c7fef33 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent
2021/05/18 11:54 upstream 8ac91e6c6033 a343ba6b .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent
* Struck through repros no longer work on HEAD.