[moderation] [ext4?] KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4535e1a4174c x86/bugs: Fix the SRSO mitigation on Zen3/4
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1128321d180000
kernel config: https://syzkaller.appspot.com/x/.config?x=aa27611f143168c9
dashboard link: https://syzkaller.appspot.com/bug?extid=6b1d8d9f05c6b7ec1240
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [adilger...@dilger.ca linux...@vger.kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org ty...@mit.edu]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a2a278a8c64b/disk-4535e1a4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/281650213121/vmlinux-4535e1a4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2498c83ebc58/bzImage-4535e1a4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6b1d8d...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked

read-write to 0xffff888106205890 of 8 bytes by task 49 on cpu 1:
redirty_tail_locked+0x56/0x270 fs/fs-writeback.c:1347
requeue_inode fs/fs-writeback.c:1608 [inline]
writeback_sb_inodes+0x893/0xaa0 fs/fs-writeback.c:1970
wb_writeback+0x252/0x6f0 fs/fs-writeback.c:2117
wb_do_writeback fs/fs-writeback.c:2264 [inline]
wb_workfn+0x1a8/0x940 fs/fs-writeback.c:2304
process_one_work kernel/workqueue.c:3254 [inline]
process_scheduled_works+0x465/0x990 kernel/workqueue.c:3335
worker_thread+0x526/0x730 kernel/workqueue.c:3416
kthread+0x1d1/0x210 kernel/kthread.c:388
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

read to 0xffff888106205890 of 8 bytes by task 7384 on cpu 0:
__mark_inode_dirty+0x19f/0x7e0 fs/fs-writeback.c:2499
mark_buffer_dirty+0x165/0x250 fs/buffer.c:1204
__block_commit_write fs/buffer.c:2177 [inline]
block_write_end+0x158/0x2e0 fs/buffer.c:2253
ext4_da_do_write_end fs/ext4/inode.c:2955 [inline]
ext4_da_write_end+0x1ad/0x860 fs/ext4/inode.c:3028
generic_perform_write+0x276/0x410 mm/filemap.c:3985
ext4_buffered_write_iter+0x1f6/0x380 fs/ext4/file.c:299
ext4_file_write_iter+0x29f/0xe30
__kernel_write_iter+0x265/0x490 fs/read_write.c:523
dump_emit_page fs/coredump.c:890 [inline]
dump_user_range+0x3a7/0x550 fs/coredump.c:951
elf_core_dump+0x1aa6/0x1bc0 fs/binfmt_elf.c:2077
do_coredump+0x1033/0x1890 fs/coredump.c:764
get_signal+0xdc1/0x1080 kernel/signal.c:2896
arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x59/0x130 kernel/entry/common.c:218
do_syscall_64+0xe2/0x1d0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x72/0x7a

value changed: 0x0000000000020084 -> 0x0000000000000004

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7384 Comm: syz-executor.4 Tainted: G W 6.9.0-rc1-syzkaller-00206-g4535e1a4174c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================


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