avfilter/vf_showinfo: check sd->size before reference the sd->data

Or it'll cause null pointer dereference if size < sizeof(uint32_t), also
in case tc[0] > 3, the code will report error directly.

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
This commit is contained in:
Limin Wang 2020-07-04 20:32:58 +08:00
parent 1dee8bf909
commit 3ede8acba6
1 changed files with 4 additions and 4 deletions

View File

@ -365,15 +365,15 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
break;
case AV_FRAME_DATA_S12M_TIMECODE: {
uint32_t *tc = (uint32_t*)sd->data;
int m = FFMIN(tc[0],3);
if (sd->size != 16) {
if ((sd->size != sizeof(uint32_t) * 4) || (tc[0] > 3)) {
av_log(ctx, AV_LOG_ERROR, "invalid data\n");
break;
}
for (int j = 1; j <= m; j++) {
for (int j = 1; j <= tc[0]; j++) {
char tcbuf[AV_TIMECODE_STR_SIZE];
av_timecode_make_smpte_tc_string(tcbuf, tc[j], 0);
av_log(ctx, AV_LOG_INFO, "timecode - %s%s", tcbuf, j != m ? ", " : "");
av_log(ctx, AV_LOG_INFO, "timecode - %s%s", tcbuf, j != tc[0] ? ", " : "");
}
break;
}