From 0a5d705e471c975ca6ca4547cd3a0eb5fa5d3291 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Mon, 27 Nov 2017 17:28:39 +0100 Subject: [PATCH 7/9] qcow2: Prevent backing file names longer than 1023 RH-Author: Max Reitz Message-id: <20171127172839.22264-2-mreitz@redhat.com> Patchwork-id: 77916 O-Subject: [RHEL-7.5 qemu-kvm PATCH 1/1] qcow2: Prevent backing file names longer than 1023 Bugzilla: 1459714 RH-Acked-by: John Snow RH-Acked-by: Fam Zheng RH-Acked-by: Stefan Hajnoczi We reject backing file names with a length of more than 1023 characters when opening a qcow2 file, so we should not produce such files ourselves. Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz Signed-off-by: Kevin Wolf (cherry picked from commit 4e876bcf2bdb3a7353df92d19bfec0afd1650bc4) Signed-off-by: Max Reitz Signed-off-by: Miroslav Rezanina --- block/qcow2.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/block/qcow2.c b/block/qcow2.c index 61f7e57..dc831ba 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1497,6 +1497,10 @@ static int qcow2_change_backing_file(BlockDriverState *bs, { BDRVQcowState *s = bs->opaque; + if (backing_file && strlen(backing_file) > 1023) { + return -EINVAL; + } + pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); -- 1.8.3.1