avcodec/mjpegdec: Check for odd progressive RGB

Fixes: out of array access
Fixes: 9225/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_JPEGLS_fuzzer-5684770334834688

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit ee1e3ca5eb)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/mjpegdec.c

@@ -593,6 +593,10 @@ unk_pixfmt:
         av_log(s->avctx, AV_LOG_ERROR, "lowres not supported for weird subsampling\n");
         return AVERROR_PATCHWELCOME;
     }
+    if ((AV_RB32(s->upscale_h) || AV_RB32(s->upscale_v)) && s->progressive && s->avctx->pix_fmt == AV_PIX_FMT_GBRP) {
+        avpriv_report_missing_feature(s->avctx, "progressive for weird subsampling");
+        return AVERROR_PATCHWELCOME;
+    }
     if (s->ls) {
         memset(s->upscale_h, 0, sizeof(s->upscale_h));
         memset(s->upscale_v, 0, sizeof(s->upscale_v));