From 708e84cda1bdbffb92847f3d6ccf6fbeb26d9948 Mon Sep 17 00:00:00 2001 From: Mark Thompson Date: Sun, 29 Jan 2017 19:45:59 +0000 Subject: [PATCH] mov: Avoid memcmp of uninitialised data The string codec name need not be as long as the value we are comparing it to, so memcmp may make decisions derived from uninitialised data that valgrind then complains about (though the overall result of the function will always be the same). Use strncmp instead, which will stop at the first zero byte and therefore not encounter this issue. --- libavformat/mov.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavformat/mov.c b/libavformat/mov.c index 37afe79df0..9afd0202ca 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -1455,11 +1455,11 @@ static void mov_parse_stsd_video(MOVContext *c, AVIOContext *pb, av_dict_set(&st->metadata, "encoder", codec_name, 0); /* codec_tag YV12 triggers an UV swap in rawdec.c */ - if (!memcmp(codec_name, "Planar Y'CbCr 8-bit 4:2:0", 25)) + if (!strncmp(codec_name, "Planar Y'CbCr 8-bit 4:2:0", 25)) st->codecpar->codec_tag = MKTAG('I', '4', '2', '0'); /* Flash Media Server uses tag H.263 with Sorenson Spark */ if (st->codecpar->codec_tag == MKTAG('H','2','6','3') && - !memcmp(codec_name, "Sorenson H263", 13)) + !strncmp(codec_name, "Sorenson H263", 13)) st->codecpar->codec_id = AV_CODEC_ID_FLV1; st->codecpar->bits_per_coded_sample = avio_rb16(pb); /* depth */