From 0adfa1ed655904d5bf17fe047635a563f0229789 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Mon, 12 Jan 2015 12:31:32 +0000 Subject: [PATCH] qed: check for header size overflow Header size is denoted in clusters. The maximum cluster size is 64 MB but there is no limit on header size. Check for uint32_t overflow in case the header size field has a whacky value. Signed-off-by: Stefan Hajnoczi Message-id: 1421065893-18875-2-git-send-email-stefanha@redhat.com Reviewed-by: Kevin Wolf Signed-off-by: Kevin Wolf --- block/qed.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/block/qed.c b/block/qed.c index 80f18d82e2..892b13c806 100644 --- a/block/qed.c +++ b/block/qed.c @@ -440,6 +440,11 @@ static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags, s->l2_mask = s->table_nelems - 1; s->l1_shift = s->l2_shift + ffs(s->table_nelems) - 1; + /* Header size calculation must not overflow uint32_t */ + if (s->header.header_size > UINT32_MAX / s->header.cluster_size) { + return -EINVAL; + } + if ((s->header.features & QED_F_BACKING_FILE)) { if ((uint64_t)s->header.backing_filename_offset + s->header.backing_filename_size >