From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Elder Subject: [PATCH 02/11] rbd: don't over-allocate space for object prefix Date: Fri, 24 Aug 2012 11:32:37 -0500 Message-ID: <5037ACA5.5060203@inktank.com> References: <5037AB20.4000103@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ob0-f174.google.com ([209.85.214.174]:58290 "EHLO mail-ob0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759622Ab2HXQcn (ORCPT ); Fri, 24 Aug 2012 12:32:43 -0400 Received: by mail-ob0-f174.google.com with SMTP id uo13so4590607obb.19 for ; Fri, 24 Aug 2012 09:32:43 -0700 (PDT) In-Reply-To: <5037AB20.4000103@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: ceph-devel@vger.kernel.org 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 NUL-terminated string from the on-disk header--or the maximum size of no NUL is found. Signed-off-by: Alex Elder --- 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 81b5344..a8a4cba 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->block_name) + 1; - header->object_prefix = kmalloc(size, GFP_KERNEL); + len = strnlen(ondisk->block_name, sizeof (ondisk->block_name)); + header->object_prefix = kmalloc(len + 1, GFP_KERNEL); if (!header->object_prefix) return -ENOMEM; - memcpy(header->object_prefix, ondisk->block_name, size - 1); - header->object_prefix[size - 1] = '\0'; + memcpy(header->object_prefix, ondisk->block_name, len); + header->object_prefix[len] = '\0'; if (snap_count) { header->snap_names_len = le64_to_cpu(ondisk->snap_names_len); -- 1.7.9.5