Commit 05cc758a authored Jun 13, 2017 by Max Reitz

blkverify: Catch bs->exact_filename overflow



The bs->exact_filename field may not be sufficient to store the full
blkverify node filename. In this case, we should not generate a filename
at all instead of an unusable one.

Cc: qemu-stable@nongnu.org
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170613172006.19685-3-mreitz@redhat.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

parent de81d72d

block/blkverify.c

+8 −4

Original line number	Diff line number	Diff line
		@@ -301,10 +301,14 @@ static void blkverify_refresh_filename(BlockDriverState bs, QDict options)
		if (bs->file->bs->exact_filename[0]
		&& s->test_file->bs->exact_filename[0])
		{
		snprintf(bs->exact_filename, sizeof(bs->exact_filename),
		int ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename),
		"blkverify:%s:%s",
		bs->file->bs->exact_filename,
		s->test_file->bs->exact_filename);
		if (ret >= sizeof(bs->exact_filename)) {
		/* An overflow makes the filename unusable, so do not report any */
		bs->exact_filename[0] = 0;
		}
		}
		}