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KCSAN: data-race in do_mpage_readpage / generic_write_end

Status: auto-closed as invalid on 2022/03/28 21:29
Subsystems: exfat
[Documentation on labels]
First crash: 811d, last: 765d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_mpage_readpage / generic_write_end (2) exfat 2 698d 700d 0/26 auto-closed as invalid on 2022/06/04 04:56
upstream KCSAN: data-race in do_mpage_readpage / generic_write_end (4) exfat 1 169d 169d 0/26 auto-obsoleted due to no activity on 2023/11/15 12:16
upstream KCSAN: data-race in do_mpage_readpage / generic_write_end (3) exfat 1 628d 628d 0/26 auto-closed as invalid on 2022/08/13 10:00

Sample crash report:
==================================================================
BUG: KCSAN: data-race in do_mpage_readpage / generic_write_end

write to 0xffff888128169218 of 8 bytes by task 5369 on cpu 1:
 i_size_write include/linux/fs.h:907 [inline]
 generic_write_end+0x96/0x180 fs/buffer.c:2187
 fat_write_end+0x4a/0x160 fs/fat/inode.c:249
 generic_perform_write+0x261/0x400 mm/filemap.c:3776
 __generic_file_write_iter+0x195/0x2b0 mm/filemap.c:3860
 generic_file_write_iter+0x75/0x130 mm/filemap.c:3924
 call_write_iter include/linux/fs.h:2074 [inline]
 do_iter_readv_writev+0x2de/0x380 fs/read_write.c:725
 do_iter_write+0x192/0x5c0 fs/read_write.c:851
 vfs_iter_write+0x4c/0x70 fs/read_write.c:892
 iter_file_splice_write+0x43a/0x790 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+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888128169218 of 8 bytes by task 5379 on cpu 0:
 i_size_read include/linux/fs.h:885 [inline]
 do_mpage_readpage+0x160/0xfd0 fs/mpage.c:190
 mpage_readahead+0x188/0x2c0 fs/mpage.c:382
 fat_readahead+0x18/0x20 fs/fat/inode.c:215
 read_pages+0xba/0x5f0 mm/readahead.c:129
 page_cache_ra_unbounded+0x16a/0x400 mm/readahead.c:210
 ondemand_readahead+0x4f8/0x700
 page_cache_sync_ra+0xaf/0xe0 mm/readahead.c:579
 page_cache_sync_readahead include/linux/pagemap.h:1056 [inline]
 filemap_get_pages mm/filemap.c:2589 [inline]
 filemap_read+0x3ed/0x1430 mm/filemap.c:2676
 generic_file_read_iter+0x72/0x320 mm/filemap.c:2822
 call_read_iter include/linux/fs.h:2068 [inline]
 generic_file_splice_read+0x24f/0x330 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+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x000000000005b000 -> 0x000000000005c000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5379 Comm: syz-executor.1 Not tainted 5.17.0-rc5-syzkaller-00004-g038101e6b2cd-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/21 21:24 upstream 038101e6b2cd 6e821dbf .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_mpage_readpage / generic_write_end
2022/02/15 01:01 upstream d567f5db412e 8b9ca619 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_mpage_readpage / generic_write_end
2022/02/13 20:18 upstream 42964a18f81c 8b9ca619 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_mpage_readpage / generic_write_end
2022/02/07 21:37 upstream 2ade8eef993c a7dab638 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_mpage_readpage / generic_write_end
2022/02/01 12:19 upstream 26291c54e111 c1c1631d .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_mpage_readpage / generic_write_end
2022/01/07 13:33 upstream ddec8ed2d490 6acc789a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_mpage_readpage / generic_write_end
* Struck through repros no longer work on HEAD.