syzbot reported a null-ptr-deref in bch2_fs_start. [0]
When a sb is marked clear but doesn't have a clean section
bch2_read_superblock_clean returns NULL which PTR_ERR_OR_ZERO
lets through, eventually leading to a null ptr dereference down
the line. Adjust read sb clean to return an ERR_PTR indicating the
invalid clean section.
[0] https://syzkaller.appspot.com/bug?extid=
1cecc37d87c4286e5543
Reported-by: syzbot+1cecc37d87c4286e5543@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1cecc37d87c4286e5543
Signed-off-by: Diogo Jahchan Koike <djahchankoike@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
SET_BCH_SB_CLEAN(c->disk_sb.sb, false);
c->sb.clean = false;
mutex_unlock(&c->sb_lock);
- return NULL;
+ return ERR_PTR(-BCH_ERR_invalid_sb_clean);
}
clean = kmemdup(sb_clean, vstruct_bytes(&sb_clean->field),