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KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages

Status: auto-closed as invalid on 2021/07/08 08:36
Subsystems: ext4
[Documentation on labels]
First crash: 1082d, last: 1058d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (4) ext4 6 858d 879d 0/26 auto-closed as invalid on 2022/01/24 21:33
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (3) ext4 13 917d 976d 0/26 auto-closed as invalid on 2021/11/26 15:32
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (6) ext4 5 718d 719d 0/26 closed as invalid on 2022/05/13 11:20
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (2) ext4 2 1012d 1016d 0/26 auto-closed as invalid on 2021/08/23 09:16
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (5) ext4 2 812d 815d 0/26 auto-closed as invalid on 2022/03/11 03:48

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages

write to 0xffff888151d6c210 of 8 bytes by task 22117 on cpu 1:
 i_size_write include/linux/fs.h:871 [inline]
 ext4_dio_write_end_io+0xd3/0x100 fs/ext4/file.c:399
 iomap_dio_complete+0xb8/0x3c0 fs/iomap/direct-io.c:88
 iomap_dio_rw+0x4e/0x70 fs/iomap/direct-io.c:652
 ext4_dio_write_iter fs/ext4/file.c:568 [inline]
 ext4_file_write_iter+0xa4f/0x11d0 fs/ext4/file.c:678
 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 0xffff888151d6c210 of 8 bytes by task 22125 on cpu 0:
 i_size_read include/linux/fs.h:849 [inline]
 ext4_readpage_limit fs/ext4/readpage.c:221 [inline]
 ext4_mpage_readpages+0x34b/0x1130 fs/ext4/readpage.c:265
 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
 do_page_cache_ra+0xa7/0xc0 mm/readahead.c:267
 do_sync_mmap_readahead+0x32b/0x360 mm/filemap.c:2903
 filemap_fault+0x1c9/0x7b0 mm/filemap.c:2990
 ext4_filemap_fault+0x4b/0x60 fs/ext4/inode.c:6194
 __do_fault mm/memory.c:3678 [inline]
 do_read_fault mm/memory.c:3980 [inline]
 do_fault mm/memory.c:4108 [inline]
 handle_pte_fault mm/memory.c:4367 [inline]
 __handle_mm_fault mm/memory.c:4502 [inline]
 handle_mm_fault+0xe8d/0x1a70 mm/memory.c:4600
 faultin_page mm/gup.c:908 [inline]
 __get_user_pages+0x947/0xee0 mm/gup.c:1127
 populate_vma_page_range mm/gup.c:1460 [inline]
 __mm_populate+0x24d/0x380 mm/gup.c:1508
 mm_populate include/linux/mm.h:2621 [inline]
 vm_mmap_pgoff+0x145/0x1d0 mm/util.c:524
 ksys_mmap_pgoff+0x2a8/0x380 mm/mmap.c:1638
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000160000 -> 0x0000000000170000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 22125 Comm: syz-executor.2 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/06/03 08:36 upstream 324c92e5e0ee 0740de69 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
2021/05/16 04:20 upstream c12a29ed9094 f54a5c09 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
2021/05/10 12:29 upstream 6efb943b8616 ca873091 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
* Struck through repros no longer work on HEAD.