Commit 8d4ce7d3d5 for ffmpeg

commit 8d4ce7d3d592d93719f248bc7d746715837a5c4a
Author: Michael Niedermayer <michael@niedermayer.cc>
Date:   Wed Nov 11 18:51:39 2026 +0100

    avcodec/iff: clear the mask palette table

    Fixes: use of uninitialized memory
    Fixes: dLFZWeypJpSK
    Fixes: ilbm-mask-short-cmap.ilbm
    Use of uninitialized memory Replicated through UnModified FFmpeg with MSAN

    Found-by: zx (Jace)

diff --git a/libavcodec/iff.c b/libavcodec/iff.c
index 66839c3c39..169cda28e0 100644
--- a/libavcodec/iff.c
+++ b/libavcodec/iff.c
@@ -254,7 +254,7 @@ static int extract_header(AVCodecContext *const avctx,
             s->mask_buf = av_malloc((s->planesize * 32) + AV_INPUT_BUFFER_PADDING_SIZE);
             if (!s->mask_buf)
                 return AVERROR(ENOMEM);
-            s->mask_palbuf = av_malloc((2 << s->bpp) * sizeof(uint32_t) + AV_INPUT_BUFFER_PADDING_SIZE);
+            s->mask_palbuf = av_mallocz((2 << s->bpp) * sizeof(uint32_t) + AV_INPUT_BUFFER_PADDING_SIZE);
             if (!s->mask_palbuf)
                 return AVERROR(ENOMEM);
         }