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KCSAN: data-race in ext4_sync_file / jbd2_journal_commit_transaction

Status: auto-closed as invalid on 2021/04/08 18:57
Subsystems: ext4
[Documentation on labels]
First crash: 1148d, last: 1120d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_sync_file / jbd2_journal_commit_transaction

write to 0xffff8881443f5800 of 8 bytes by task 4809 on cpu 0:
 jbd2_journal_commit_transaction+0x228/0x3290 fs/jbd2/commit.c:443
 kjournald2+0x263/0x480 fs/jbd2/journal.c:213
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff8881443f5800 of 8 bytes by task 10828 on cpu 1:
 ext4_fsync_journal fs/ext4/fsync.c:111 [inline]
 ext4_sync_file+0x24a/0x6e0 fs/ext4/fsync.c:174
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2843 [inline]
 ext4_buffered_write_iter+0x38f/0x3e0 fs/ext4/file.c:277
 ext4_file_write_iter+0x48a/0x10b0 fs/ext4/file.c:502
 call_write_iter include/linux/fs.h:1977 [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+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1319 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10828 Comm: syz-executor.1 Not tainted 5.12.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/03/04 18:51 upstream f69d02e37a85 f89ed068 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_sync_file / jbd2_journal_commit_transaction
2021/02/12 19:01 upstream dcc0b49040c7 98682e5e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_sync_file / jbd2_journal_commit_transaction
2021/02/12 07:14 upstream dcc0b49040c7 a5f86b15 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_sync_file / jbd2_journal_commit_transaction
2021/02/05 12:45 upstream dd86e7fa07a3 23a562df .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_sync_file / jbd2_journal_commit_transaction
* Struck through repros no longer work on HEAD.