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KCSAN: data-race in __add_to_page_cache_locked / file_write_and_wait_range

Status: closed as invalid on 2020/06/18 14:24
Subsystems: ext4
[Documentation on labels]
First crash: 2159d, last: 1948d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __add_to_page_cache_locked / file_write_and_wait_range (2) mm fs 6 135 1460d 1801d 0/29 auto-closed as invalid on 2021/11/20 00:15

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __add_to_page_cache_locked / file_write_and_wait_range

write to 0xffff8880b91c49c0 of 8 bytes by task 21382 on cpu 0:
 __add_to_page_cache_locked+0x28a/0x800 mm/filemap.c:868
 add_to_page_cache_lru+0xc7/0x260 mm/filemap.c:921
 pagecache_get_page+0x2b0/0x8c0 mm/filemap.c:1656
 grab_cache_page_write_begin+0x56/0x80 mm/filemap.c:3252
 ext4_da_write_begin+0x1b4/0xa10 fs/ext4/inode.c:2964
 generic_perform_write+0x13a/0x320 mm/filemap.c:3302
 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

read to 0xffff8880b91c49c0 of 8 bytes by task 21385 on cpu 1:
 mapping_needs_writeback mm/filemap.c:632 [inline]
 file_write_and_wait_range+0x7c/0x160 mm/filemap.c:759
 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:1576 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0xb8/0x140 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: 21385 Comm: syz-executor.4 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
2020/06/14 22:18 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 2a22c77a .config console log report ci2-upstream-kcsan-gce
2020/06/14 05:20 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a61674a5 .config console log report ci2-upstream-kcsan-gce
2020/06/12 23:15 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 3036d6fd .config console log report ci2-upstream-kcsan-gce
2020/06/09 10:36 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 0d60b78a .config console log report ci2-upstream-kcsan-gce
2020/06/04 16:44 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 6720fdef .config console log report ci2-upstream-kcsan-gce
2020/05/06 06:32 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 35b8eb30 .config console log report ci2-upstream-kcsan-gce
2020/05/03 22:55 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 58ae5e18 .config console log report ci2-upstream-kcsan-gce
2020/04/14 06:02 https://github.com/google/ktsan.git kcsan 40959e34d670 7c54686a .config console log report ci2-upstream-kcsan-gce
2020/04/09 13:04 https://github.com/google/ktsan.git kcsan 40959e34d670 a8c6a3f8 .config console log report ci2-upstream-kcsan-gce
2020/04/04 02:01 https://github.com/google/ktsan.git kcsan 40959e34d670 ef26b610 .config console log report ci2-upstream-kcsan-gce
2020/03/27 14:00 https://github.com/google/ktsan.git kcsan 40959e34d670 831e9a81 .config console log report ci2-upstream-kcsan-gce
2020/03/13 10:27 https://github.com/google/ktsan.git kcsan 941e0d917bbf fd69032d .config console log report ci2-upstream-kcsan-gce
2020/02/11 11:08 https://github.com/google/ktsan.git kcsan f60f0f543333 084454ae .config console log report ci2-upstream-kcsan-gce
2020/02/10 05:28 https://github.com/google/ktsan.git kcsan f60f0f543333 35f5e45e .config console log report ci2-upstream-kcsan-gce
2020/02/03 12:19 https://github.com/google/ktsan.git kcsan 245a43005292 93e5e335 .config console log report ci2-upstream-kcsan-gce
2020/01/26 19:49 https://github.com/google/ktsan.git kcsan 245a43005292 dd56146d .config console log report ci2-upstream-kcsan-gce
2020/01/10 02:51 https://github.com/google/ktsan.git kcsan 245a43005292 4de4e9f0 .config console log report ci2-upstream-kcsan-gce
2019/11/16 17:56 https://github.com/google/ktsan.git kcsan 5863cc791e4c cdac920b .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.