From: Xiyu Yang <[email protected]> commit 3bbd0ef26098d241dc59ee77ba14b7dab0df0786 upstream.
ext4_orphan_get() invokes ext4_read_inode_bitmap(), which returns a reference of the specified buffer_head object to "bitmap_bh" with increased refcnt. When ext4_orphan_get() returns, local variable "bitmap_bh" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of ext4_orphan_get(). When ext4_iget() fails, the function forgets to decrease the refcnt increased by ext4_read_inode_bitmap(), causing a refcnt leak. Fix this issue by calling brelse() when ext4_iget() fails. Signed-off-by: Xiyu Yang <[email protected]> Signed-off-by: Xin Tan <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Theodore Ts'o <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/ext4/ialloc.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -1246,6 +1246,7 @@ struct inode *ext4_orphan_get(struct sup ext4_error_err(sb, -err, "couldn't read orphan inode %lu (err %d)", ino, err); + brelse(bitmap_bh); return inode; }
