[FFmpeg-cvslog] avformat/mxfdec: Don't pretend array to be bigger than it is

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Mon Sep 11 17:43:40 2023 +0200| [58aaa83fa2eb72a6682129c6238c73a5bf39fafc] | committer: Andreas Rheinhardt

avformat/mxfdec: Don't pretend array to be bigger than it is

mxf_match_uid() accepts two const UID and a len parameter.
UID is a typedef for an array of 16 uint8_t, so the const UID
parameter is actually a pointer to const uint8_t.

The point of mxf_match_uid() is to check whether the initial
part of two UIDs match; the length of said part is given
by the len parameter. Once an incomplete UID has been passed
to mxf_match_uid() (albeit with the correct len, so safe),
which makes GCC emit -Wstringop-overread warnings.

Fix this by using a const uint8_t[] as type; it is more
natural for incomplete UIDs.

Reviewed-by: Tomas Härdin <git at haerdin.se>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=58aaa83fa2eb72a6682129c6238c73a5bf39fafc
---

 libavformat/mxfdec.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index 7dbe294d23..4846c5d206 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -1544,11 +1544,11 @@ static int mxf_read_tagged_value(void *arg, AVIOContext *pb, int tag, int size,
  * Match an uid independently of the version byte and up to len common bytes
  * Returns: boolean
  */
-static int mxf_match_uid(const UID key, const UID uid, int len)
+static int mxf_match_uid(const UID key, const uint8_t uid_prefix[], int len)
 {
     int i;
     for (i = 0; i < len; i++) {
-        if (i != 7 && key[i] != uid[i])
+        if (i != 7 && key[i] != uid_prefix[i])
             return 0;
     }
     return 1;