diff options
author | Xi Wang <xi.wang@gmail.com> | 2013-01-23 06:40:05 +0400 |
---|---|---|
committer | Martin Storsjö <martin@martin.st> | 2013-01-23 15:51:28 +0400 |
commit | ecb918e5f0a4395468862b5fbd11a51de9be3d4f (patch) | |
tree | 42128fdf9170a379234e023ec6a7822636c0c7bb /libavformat | |
parent | 3cff53369acdb3bc0695dd6d5df51457fdaa16ce (diff) |
rtmp: fix buffer overflows in ff_amf_tag_contents()
A negative `size' will bypass FFMIN(). In the subsequent memcpy() call,
`size' will be considered as a large positive value, leading to a buffer
overflow.
Change the type of `size' to unsigned int to avoid buffer overflow, and
simplify overflow checks accordingly. Also change a literal buffer
size to use sizeof, and limit the amount of data copied in another
memcpy call as well.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
Diffstat (limited to 'libavformat')
-rw-r--r-- | libavformat/rtmppkt.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/libavformat/rtmppkt.c b/libavformat/rtmppkt.c index a9d0a0d9f3..119cdfa765 100644 --- a/libavformat/rtmppkt.c +++ b/libavformat/rtmppkt.c @@ -440,7 +440,7 @@ static const char* rtmp_packet_type(int type) static void ff_amf_tag_contents(void *ctx, const uint8_t *data, const uint8_t *data_end) { - int size; + unsigned int size; char buf[1024]; if (data >= data_end) @@ -459,7 +459,7 @@ static void ff_amf_tag_contents(void *ctx, const uint8_t *data, const uint8_t *d } else { size = bytestream_get_be32(&data); } - size = FFMIN(size, 1023); + size = FFMIN(size, sizeof(buf) - 1); memcpy(buf, data, size); buf[size] = 0; av_log(ctx, AV_LOG_DEBUG, " string '%s'\n", buf); @@ -472,16 +472,15 @@ static void ff_amf_tag_contents(void *ctx, const uint8_t *data, const uint8_t *d case AMF_DATA_TYPE_OBJECT: av_log(ctx, AV_LOG_DEBUG, " {\n"); for (;;) { - int size = bytestream_get_be16(&data); int t; - memcpy(buf, data, size); - buf[size] = 0; + size = bytestream_get_be16(&data); + av_strlcpy(buf, data, FFMIN(sizeof(buf), size + 1)); if (!size) { av_log(ctx, AV_LOG_DEBUG, " }\n"); data++; break; } - if (size < 0 || size >= data_end - data) + if (size >= data_end - data) return; data += size; av_log(ctx, AV_LOG_DEBUG, " %s: ", buf); |