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KCSAN: data-race in filemap_fdatawrite_wbc / xas_clear_mark (4)

Status: auto-obsoleted due to no activity on 2024/07/19 18:06
Subsystems: fs mm
[Documentation on labels]
Reported-by: syzbot+fc30ed4b106b4bd08f6b@syzkaller.appspotmail.com
First crash: 35d, last: 35d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in filemap_fdatawrite_wbc / xas_clear_mark (2) fs mm 1 442d 442d 0/27 auto-obsoleted due to no activity on 2023/06/08 03:34
upstream KCSAN: data-race in filemap_fdatawrite_wbc / xas_clear_mark (3) mm fs 2 241d 221d 0/27 auto-obsoleted due to no activity on 2023/12/26 21:21
upstream KCSAN: data-race in filemap_fdatawrite_wbc / xas_clear_mark mm fs 1 549d 549d 0/27 auto-obsoleted due to no activity on 2023/03/14 19:57

Sample crash report:
==================================================================
BUG: KCSAN: data-race in filemap_fdatawrite_wbc / xas_clear_mark

write to 0xffff888106aede0c of 4 bytes by task 10249 on cpu 1:
 xa_mark_clear lib/xarray.c:77 [inline]
 xas_clear_mark+0x169/0x180 lib/xarray.c:925
 __folio_start_writeback+0x2e2/0x450 mm/page-writeback.c:3103
 ext4_bio_write_folio+0x58b/0x9a0 fs/ext4/page-io.c:554
 mpage_submit_folio fs/ext4/inode.c:1869 [inline]
 mpage_map_and_submit_buffers fs/ext4/inode.c:2115 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2254 [inline]
 ext4_do_writepages+0x13a6/0x2110 fs/ext4/inode.c:2679
 ext4_writepages+0x159/0x2e0 fs/ext4/inode.c:2768
 do_writepages+0x1d8/0x480 mm/page-writeback.c:2634
 filemap_fdatawrite_wbc+0xdb/0x100 mm/filemap.c:397
 __filemap_fdatawrite_range mm/filemap.c:430 [inline]
 file_write_and_wait_range+0xc8/0x170 mm/filemap.c:788
 ext4_sync_file+0x134/0x6c0 fs/ext4/fsync.c:158
 vfs_fsync_range+0x122/0x140 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2794 [inline]
 ext4_buffered_write_iter+0x338/0x380 fs/ext4/file.c:305
 ext4_file_write_iter+0x29f/0xe30
 iter_file_splice_write+0x5e6/0x970 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x16c/0x2c0 fs/splice.c:1164
 splice_direct_to_actor+0x305/0x670 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x960 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 x64_sys_call+0x2c9f/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888106aede0c of 4 bytes by task 10250 on cpu 0:
 xa_marked include/linux/xarray.h:424 [inline]
 mapping_tagged include/linux/fs.h:498 [inline]
 filemap_fdatawrite_wbc+0x5c/0x100 mm/filemap.c:393
 __filemap_fdatawrite_range mm/filemap.c:430 [inline]
 filemap_write_and_wait_range+0xb6/0x1f0 mm/filemap.c:685
 kiocb_invalidate_pages+0x87/0x1e0 mm/filemap.c:2727
 __iomap_dio_rw+0x585/0x1090 fs/iomap/direct-io.c:639
 iomap_dio_rw+0x40/0x90 fs/iomap/direct-io.c:749
 ext4_dio_write_iter fs/ext4/file.c:577 [inline]
 ext4_file_write_iter+0xaa4/0xe30 fs/ext4/file.c:696
 iter_file_splice_write+0x5e6/0x970 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x16c/0x2c0 fs/splice.c:1164
 splice_direct_to_actor+0x305/0x670 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x960 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 x64_sys_call+0x2c9f/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0e000021 -> 0x04000021

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10250 Comm: syz-executor.1 Not tainted 6.10.0-rc3-syzkaller-00109-g0cac73eb3875 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/14 18:06 upstream 0cac73eb3875 8d849073 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in filemap_fdatawrite_wbc / xas_clear_mark
* Struck through repros no longer work on HEAD.