syzbot


KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (3)
Status: auto-closed as invalid on 2020/10/29 18:32
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 702d, last: 611d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (4) 5 525d 537d 0/22 auto-closed as invalid on 2021/01/23 11:44
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers 8 849d 919d 0/22 auto-closed as invalid on 2020/04/08 22:27
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (2) 1 740d 740d 0/22 closed as invalid on 2020/06/18 14:13
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (5) 32 215d 442d 0/22 auto-closed as invalid on 2021/11/29 11:14

Sample crash report:
==================================================================
BUG: KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers

write to 0xffff888115ec52c8 of 8 bytes by task 20277 on cpu 1:
 __remove_assoc_queue fs/buffer.c:481 [inline]
 fsync_buffers_list fs/buffer.c:713 [inline]
 sync_mapping_buffers+0x155/0x7d0 fs/buffer.c:548
 fat_file_fsync+0xa9/0x100 fs/fat/file.c:194
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2747 [inline]
 generic_file_write_iter+0x3af/0x3e0 mm/filemap.c:3666
 call_write_iter include/linux/fs.h:1882 [inline]
 do_iter_readv_writev+0x32e/0x3d0 fs/read_write.c:713
 do_iter_write+0x112/0x4b0 fs/read_write.c:1018
 vfs_iter_write+0x4c/0x70 fs/read_write.c:1059
 iter_file_splice_write+0x41a/0x770 fs/splice.c:750
 do_splice_from fs/splice.c:846 [inline]
 direct_splice_actor+0x95/0x160 fs/splice.c:1016
 splice_direct_to_actor+0x365/0x660 fs/splice.c:971
 do_splice_direct+0xf2/0x170 fs/splice.c:1059
 do_sendfile+0x56a/0xba0 fs/read_write.c:1540
 __do_sys_sendfile64 fs/read_write.c:1601 [inline]
 __se_sys_sendfile64 fs/read_write.c:1587 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1587
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888115ec52c8 of 8 bytes by task 20271 on cpu 0:
 mark_buffer_dirty_inode+0x92/0x1b0 fs/buffer.c:581
 fat_mirror_bhs+0x200/0x320 fs/fat/fatent.c:396
 fat_ent_write+0xbf/0xd0 fs/fat/fatent.c:421
 fat_chain_add+0x149/0x400 fs/fat/misc.c:130
 fat_add_cluster fs/fat/inode.c:113 [inline]
 __fat_get_block fs/fat/inode.c:155 [inline]
 fat_get_block+0x429/0x5a0 fs/fat/inode.c:190
 __block_write_begin_int+0x4bf/0xfd0 fs/buffer.c:2011
 __block_write_begin fs/buffer.c:2061 [inline]
 block_write_begin+0x4f/0x1c0 fs/buffer.c:2120
 cont_write_begin+0x42c/0x610 fs/buffer.c:2469
 fat_write_begin+0x61/0xf0 fs/fat/inode.c:235
 generic_perform_write+0x196/0x390 mm/filemap.c:3501
 __generic_file_write_iter+0x154/0x330 mm/filemap.c:3630
 generic_file_write_iter+0x2f3/0x3e0 mm/filemap.c:3662
 call_write_iter include/linux/fs.h:1882 [inline]
 new_sync_write fs/read_write.c:503 [inline]
 vfs_write+0x665/0x6f0 fs/read_write.c:578
 ksys_write+0xce/0x180 fs/read_write.c:631
 __do_sys_write fs/read_write.c:643 [inline]
 __se_sys_write fs/read_write.c:640 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:640
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20271 Comm: syz-executor.0 Not tainted 5.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (10):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2020/09/24 18:28 upstream 171d4ff79f96 54289b08 .config log report info
ci2-upstream-kcsan-gce 2020/09/03 08:19 upstream fc3abb53250a abf9ba4f .config log report
ci2-upstream-kcsan-gce 2020/08/12 14:52 upstream fb893de323e2 0d7bd2e0 .config log report
ci2-upstream-kcsan-gce 2020/07/20 22:18 upstream 5714ee50bb43 8caeeeb7 .config log report
ci2-upstream-kcsan-gce 2020/07/16 08:11 upstream 994e99a96c9b ada108d0 .config log report
ci2-upstream-kcsan-gce 2020/07/13 02:24 upstream 9901a6bd1577 9ebcc5b1 .config log report
ci2-upstream-kcsan-gce 2020/07/07 11:17 upstream bfe91da29bfa 42723355 .config log report
ci2-upstream-kcsan-gce 2020/07/04 16:13 upstream 35e884f89df4 4f739670 .config log report
ci2-upstream-kcsan-gce 2020/06/27 03:04 upstream 1590a2e1c681 ffec44b5 .config log report
ci2-upstream-kcsan-gce 2020/06/25 00:40 upstream 26e122e97a3d 9d60b18e .config log report