[PATCH 6.19 653/844] xfs: remove xfs_attr_leaf_hasname

[Sasha Levin]

From: Christoph Hellwig <hch@xxxxxx>

[ Upstream commit 3a65ea768b8094e4699e72f9ab420eb9e0f3f568 ]

The calling convention of xfs_attr_leaf_hasname() is problematic, because
it returns a NULL buffer when xfs_attr3_leaf_read fails, a valid buffer
when xfs_attr3_leaf_lookup_int returns -ENOATTR or -EEXIST, and a
non-NULL buffer pointer for an already released buffer when
xfs_attr3_leaf_lookup_int fails with other error values.

Fix this by simply open coding xfs_attr_leaf_hasname in the callers, so
that the buffer release code is done by each caller of
xfs_attr3_leaf_read.

Cc: stable@xxxxxxxxxxxxxxx # v5.19+
Fixes: 07120f1abdff ("xfs: Add xfs_has_attr and subroutines")
Reported-by: Mark Tinguely <mark.tinguely@xxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Signed-off-by: Carlos Maiolino <cem@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 fs/xfs/libxfs/xfs_attr.c | 75 +++++++++++++---------------------------
 1 file changed, 24 insertions(+), 51 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 8c04acd30d489..b88e65c7e45de 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -50,7 +50,6 @@ STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
  */
 STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
-STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp);
 
 /*
  * Internal routines when attribute list is more than one block.
@@ -979,11 +978,12 @@ xfs_attr_lookup(
 		return error;
 
 	if (xfs_attr_is_leaf(dp)) {
-		error = xfs_attr_leaf_hasname(args, &bp);
-
-		if (bp)
-			xfs_trans_brelse(args->trans, bp);
-
+		error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner,
+				0, &bp);
+		if (error)
+			return error;
+		error = xfs_attr3_leaf_lookup_int(bp, args);
+		xfs_trans_brelse(args->trans, bp);
 		return error;
 	}
 
@@ -1222,27 +1222,6 @@ xfs_attr_shortform_addname(
  * External routines when attribute list is one block
  *========================================================================*/
 
-/*
- * Return EEXIST if attr is found, or ENOATTR if not
- */
-STATIC int
-xfs_attr_leaf_hasname(
-	struct xfs_da_args	*args,
-	struct xfs_buf		**bp)
-{
-	int                     error = 0;
-
-	error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner, 0, bp);
-	if (error)
-		return error;
-
-	error = xfs_attr3_leaf_lookup_int(*bp, args);
-	if (error != -ENOATTR && error != -EEXIST)
-		xfs_trans_brelse(args->trans, *bp);
-
-	return error;
-}
-
 /*
  * Remove a name from the leaf attribute list structure
  *
@@ -1253,25 +1232,22 @@ STATIC int
 xfs_attr_leaf_removename(
 	struct xfs_da_args	*args)
 {
-	struct xfs_inode	*dp;
-	struct xfs_buf		*bp;
+	struct xfs_inode	*dp = args->dp;
 	int			error, forkoff;
+	struct xfs_buf		*bp;
 
 	trace_xfs_attr_leaf_removename(args);
 
-	/*
-	 * Remove the attribute.
-	 */
-	dp = args->dp;
-
-	error = xfs_attr_leaf_hasname(args, &bp);
-	if (error == -ENOATTR) {
+	error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner, 0, &bp);
+	if (error)
+		return error;
+	error = xfs_attr3_leaf_lookup_int(bp, args);
+	if (error != -EEXIST) {
 		xfs_trans_brelse(args->trans, bp);
-		if (args->op_flags & XFS_DA_OP_RECOVERY)
+		if (error == -ENOATTR && (args->op_flags & XFS_DA_OP_RECOVERY))
 			return 0;
 		return error;
-	} else if (error != -EEXIST)
-		return error;
+	}
 
 	xfs_attr3_leaf_remove(bp, args);
 
@@ -1295,23 +1271,20 @@ xfs_attr_leaf_removename(
  * Returns 0 on successful retrieval, otherwise an error.
  */
 STATIC int
-xfs_attr_leaf_get(xfs_da_args_t *args)
+xfs_attr_leaf_get(
+	struct xfs_da_args	*args)
 {
-	struct xfs_buf *bp;
-	int error;
+	struct xfs_buf		*bp;
+	int			error;
 
 	trace_xfs_attr_leaf_get(args);
 
-	error = xfs_attr_leaf_hasname(args, &bp);
-
-	if (error == -ENOATTR)  {
-		xfs_trans_brelse(args->trans, bp);
-		return error;
-	} else if (error != -EEXIST)
+	error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner, 0, &bp);
+	if (error)
 		return error;
-
-
-	error = xfs_attr3_leaf_getvalue(bp, args);
+	error = xfs_attr3_leaf_lookup_int(bp, args);
+	if (error == -EEXIST)
+		error = xfs_attr3_leaf_getvalue(bp, args);
 	xfs_trans_brelse(args->trans, bp);
 	return error;
 }
-- 
2.51.0