ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all()

The commit c8e008b ("ext4: ignore xattrs past end")
introduced a refcount leak in when block_csum is false.

ext4_xattr_inode_dec_ref_all() calls ext4_get_inode_loc() to
get iloc.bh, but never releases it with brelse().

Fixes: c8e008b ("ext4: ignore xattrs past end")
Signed-off-by: Sohei Koyama <skoyama@ddn.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Baokun Li <libaokun@linux.alibaba.com>
Link: https://patch.msgid.link/20260406074830.8480-1-skoyama@ddn.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Author: KoyamaSohei

fs/ext4/xattr.c

@@ -1165,7 +1165,7 @@ ext4_xattr_inode_dec_ref_all(handle_t *handle, struct inode *parent,
 {
 	struct inode *ea_inode;
 	struct ext4_xattr_entry *entry;
-	struct ext4_iloc iloc;
+	struct ext4_iloc iloc = { .bh = NULL };
 	bool dirty = false;
 	unsigned int ea_ino;
 	int err;
@@ -1260,6 +1260,8 @@ ext4_xattr_inode_dec_ref_all(handle_t *handle, struct inode *parent,
 			ext4_warning_inode(parent,
 					   "handle dirty metadata err=%d", err);
 	}
+
+	brelse(iloc.bh);
 }
 
 /*