Commit c6a68b6e45 for ffmpeg

commit c6a68b6e453546dbc5afeabf7f7a1dec8ef3f1dd
Author: Michael Niedermayer <michael@niedermayer.cc>
Date:   Sat Oct 24 06:08:55 2026 +0200

    avcodec/vp9: reject frames with different U and V strides

    Fixes: K1QeU7Q1W8m1/testcase/vp9_driver.c
    Fixes: K1QeU7Q1W8m1
    Fixes: AISLE-2026-0150-00612
    Out of array write Replicated through API with ASAN

    Found-by: Joshua Rogers (AISLE)

    The report suggested using linesize[2] for the V plane throughout the
    decoder or rejecting unequal strides after get_buffer2().

    Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

diff --git a/libavcodec/vp9.c b/libavcodec/vp9.c
index 83d712bb25..3a52b8444f 100644
--- a/libavcodec/vp9.c
+++ b/libavcodec/vp9.c
@@ -114,6 +114,12 @@ static int vp9_frame_alloc(AVCodecContext *avctx, VP9Frame *f)
     if (ret < 0)
         return ret;

+    if (!avctx->hwaccel && f->tf.f->linesize[1] != f->tf.f->linesize[2]) {
+        av_log(avctx, AV_LOG_ERROR, "uv stride mismatch unsupported\n");
+        ret = AVERROR_PATCHWELCOME;
+        goto fail;
+    }
+
     sz = 64 * s->sb_cols * s->sb_rows;
     if (sz != s->frame_extradata_pool_size) {
         av_refstruct_pool_uninit(&s->frame_extradata_pool);