[PATCH v2] udf: Use kvzalloc() in udf_sb_alloc_bitmap()

[Denis Efremov <efremov@linux.com>]

Use kvzalloc() in udf_sb_alloc_bitmap() instead of open-coding it.
Size computation wrapped in struct_size() macro to prevent potential
integer overflows.

Signed-off-by: Denis Efremov <efremov@linux.com>
---
 fs/udf/super.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/fs/udf/super.c b/fs/udf/super.c
index 1c42f544096d..bdf51bea54f3 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1010,14 +1010,9 @@ static struct udf_bitmap *udf_sb_alloc_bitmap(struct super_block *sb, u32 index)
 	int size;
 
 	nr_groups = udf_compute_nr_groups(sb, index);
-	size = sizeof(struct udf_bitmap) +
-		(sizeof(struct buffer_head *) * nr_groups);
-
-	if (size <= PAGE_SIZE)
-		bitmap = kzalloc(size, GFP_KERNEL);
-	else
-		bitmap = vzalloc(size); /* TODO: get rid of vzalloc */
+	size = struct_size(bitmap, s_block_bitmap, nr_groups);
 
+	bitmap = kvzalloc(size, GFP_KERNEL);
 	if (!bitmap)
 		return NULL;
 
-- 
2.26.2