KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9e6a39ea Merge tag 'devicetree-fixes-for-5.10-2' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=138f281c500000
kernel config: https://syzkaller.appspot.com/x/.config?x=671e27f23e60a67b
dashboard link: https://syzkaller.appspot.com/bug?extid=9ebcb5d1d9e37fdc30dd
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [adilger...@dilger.ca linux...@vger.kernel.org linux-...@vger.kernel.org ty...@mit.edu]

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9ebcb5...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent

read to 0xffff88810d8dd6d8 of 8 bytes by task 13277 on cpu 1:
ext4_es_lookup_extent+0x2a8/0x500 fs/ext4/extents_status.c:966
ext4_map_blocks+0x105/0xfc0 fs/ext4/inode.c:520
ext4_iomap_begin+0x167/0x690 fs/ext4/inode.c:3470
iomap_apply+0x8d/0x4a0 fs/iomap/apply.c:46
__iomap_dio_rw+0x448/0x9b0 fs/iomap/direct-io.c:517
iomap_dio_rw+0x30/0x70 fs/iomap/direct-io.c:605
ext4_dio_read_iter fs/ext4/file.c:77 [inline]
ext4_file_read_iter+0x3bd/0x420 fs/ext4/file.c:129
call_read_iter include/linux/fs.h:1881 [inline]
generic_file_splice_read+0x22a/0x310 fs/splice.c:311
do_splice_to fs/splice.c:788 [inline]
splice_direct_to_actor+0x2aa/0x650 fs/splice.c:867
do_splice_direct+0xf5/0x170 fs/splice.c:976
do_sendfile+0x574/0xb70 fs/read_write.c:1257
__do_sys_sendfile64 fs/read_write.c:1318 [inline]
__se_sys_sendfile64 fs/read_write.c:1304 [inline]
__x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1304
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff88810d8dd6d8 of 8 bytes by task 13287 on cpu 0:
ext4_es_set_referenced fs/ext4/extents_status.h:194 [inline]
ext4_es_lookup_extent+0x2f7/0x500 fs/ext4/extents_status.c:968
ext4_map_blocks+0x105/0xfc0 fs/ext4/inode.c:520
ext4_iomap_begin+0x167/0x690 fs/ext4/inode.c:3470
iomap_apply+0x8d/0x4a0 fs/iomap/apply.c:46
__iomap_dio_rw+0x448/0x9b0 fs/iomap/direct-io.c:517
iomap_dio_rw+0x30/0x70 fs/iomap/direct-io.c:605
ext4_dio_read_iter fs/ext4/file.c:77 [inline]
ext4_file_read_iter+0x3bd/0x420 fs/ext4/file.c:129
call_read_iter include/linux/fs.h:1881 [inline]
generic_file_splice_read+0x22a/0x310 fs/splice.c:311
do_splice_to fs/splice.c:788 [inline]
splice_direct_to_actor+0x2aa/0x650 fs/splice.c:867
do_splice_direct+0xf5/0x170 fs/splice.c:976
do_sendfile+0x574/0xb70 fs/read_write.c:1257
__do_sys_sendfile64 fs/read_write.c:1318 [inline]
__se_sys_sendfile64 fs/read_write.c:1304 [inline]
__x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1304
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13287 Comm: syz-executor.0 Not tainted 5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.