[PATCH 05/28] xfs: use kmalloc_objs() instead of kmalloc() in xfs_da_grow_inode_int

[Andrey Albershteyn <aalbersh@kernel.org>]

From: Cihan Karadag <cihan.cihan@gmail.com>

Source kernel commit: 56aa9ef3c413cb13a373226f91a19358cd9f1266

Convert open-coded kmalloc() multiplication to the modern kmalloc_objs()
interface to improve type safety and prevent potential integer
overflows.

No functional changes are intended.

Signed-off-by: Cihan Karadag <cihan.cihan@gmail.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
---
 include/kmem.h        | 12 ++++++++++++
 libxfs/xfs_da_btree.c |  3 +--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/include/kmem.h b/include/kmem.h
index 2c276e929c48..4363601ff682 100644
--- a/include/kmem.h
+++ b/include/kmem.h
@@ -138,4 +138,16 @@ static inline void *kmemdup(const void *src, size_t len, gfp_t gfp)
 	return p;
 }
 
+/**
+ * kmalloc_objs - Allocate an array of the given type
+ * @VAR_OR_TYPE: Variable or type to allocate an array of.
+ * @COUNT: How many elements in the array.
+ * @...: optional GFP flags for the allocation (GFP_KERNEL when not specified).
+ *
+ * Returns: newly allocated pointer to array of @VAR_OR_TYPE on success,
+ * or NULL on failure.
+ */
+#define kmalloc_objs(VAR_OR_TYPE, COUNT, ...) \
+	__alloc_objs(kmalloc, default_gfp(__VA_ARGS__), typeof(VAR_OR_TYPE), COUNT)
+
 #endif
diff --git a/libxfs/xfs_da_btree.c b/libxfs/xfs_da_btree.c
index 9debb95d86fa..f190c088591b 100644
--- a/libxfs/xfs_da_btree.c
+++ b/libxfs/xfs_da_btree.c
@@ -2354,8 +2354,7 @@ xfs_da_grow_inode_int(
 		 * If we didn't get it and the block might work if fragmented,
 		 * try without the CONTIG flag.  Loop until we get it all.
 		 */
-		mapp = kmalloc(sizeof(*mapp) * count,
-				GFP_KERNEL | __GFP_NOFAIL);
+		mapp = kmalloc_objs(*mapp, count, GFP_KERNEL | __GFP_NOFAIL);
 		for (b = *bno, mapi = 0; b < *bno + count; ) {
 			c = (int)(*bno + count - b);
 			nmap = min(XFS_BMAP_MAX_NMAP, c);
-- 
2.54.0