From 58c17b0e1b2278824aedc5d1201f6a43a38d6a48 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Thu, 23 Aug 2012 23:22:06 -0500 Subject: [PATCH] rbd: don't over-allocate space for object prefix In rbd_header_from_disk() the object prefix buffer is sized based on the maximum size it's block_name equivalent on disk could be. Instead, only allocate enough to hold null-terminated string from the on-disk header--or the maximum size of no NUL is found. Signed-off-by: Alex Elder Reviewed-by: Yehuda Sadeh --- drivers/block/rbd.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 15bd3ecbcf34..a27167942a92 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -519,18 +519,19 @@ static int rbd_header_from_disk(struct rbd_image_header *header, struct rbd_image_header_ondisk *ondisk) { u32 snap_count; + size_t len; size_t size; memset(header, 0, sizeof (*header)); snap_count = le32_to_cpu(ondisk->snap_count); - size = sizeof (ondisk->object_prefix) + 1; - header->object_prefix = kmalloc(size, GFP_KERNEL); + len = strnlen(ondisk->object_prefix, sizeof (ondisk->object_prefix)); + header->object_prefix = kmalloc(len + 1, GFP_KERNEL); if (!header->object_prefix) return -ENOMEM; - memcpy(header->object_prefix, ondisk->object_prefix, size - 1); - header->object_prefix[size - 1] = '\0'; + memcpy(header->object_prefix, ondisk->object_prefix, len); + header->object_prefix[len] = '\0'; if (snap_count) { header->snap_names_len = le64_to_cpu(ondisk->snap_names_len); -- 2.20.1