From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:40640) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RKrtz-0003yv-Td for qemu-devel@nongnu.org; Mon, 31 Oct 2011 09:27:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RKrtt-0004Aq-Fm for qemu-devel@nongnu.org; Mon, 31 Oct 2011 09:27:42 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43003) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RKrtt-0004Ab-3E for qemu-devel@nongnu.org; Mon, 31 Oct 2011 09:27:41 -0400 From: Kevin Wolf Date: Mon, 31 Oct 2011 14:29:46 +0100 Message-Id: <1320067830-12093-12-git-send-email-kwolf@redhat.com> In-Reply-To: <1320067830-12093-1-git-send-email-kwolf@redhat.com> References: <1320067830-12093-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PATCH 11/55] vmdk: Fix possible segfaults List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: anthony@codemonkey.ws Cc: kwolf@redhat.com, qemu-devel@nongnu.org Data we read from the disk isn't necessarily null terminated and may not contain the string we're looking for. The code needs to be a bit more careful here. Signed-off-by: Kevin Wolf --- block/vmdk.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index fa0e8bd..8caaf0b 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -227,6 +227,7 @@ static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent) cid_str_size = sizeof("CID"); } + desc[DESC_SIZE - 1] = '\0'; p_name = strstr(desc, cid_str); if (p_name != NULL) { p_name += cid_str_size; @@ -243,13 +244,17 @@ static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid) BDRVVmdkState *s = bs->opaque; int ret; - memset(desc, 0, sizeof(desc)); ret = bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE); if (ret < 0) { return ret; } + desc[DESC_SIZE - 1] = '\0'; tmp_str = strstr(desc, "parentCID"); + if (tmp_str == NULL) { + return -EINVAL; + } + pstrcpy(tmp_desc, sizeof(tmp_desc), tmp_str); p_name = strstr(desc, "CID"); if (p_name != NULL) { -- 1.7.6.4