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Git pushed a commit to branch release/4.4
in repository ffmpeg.

commit f8501d3399c748f297ed7ed323f0b1f0ba194037
Author:     Michael Niedermayer <[email protected]>
AuthorDate: Tue Feb 10 18:42:07 2026 +0100
Commit:     Michael Niedermayer <[email protected]>
CommitDate: Tue May 5 18:55:11 2026 +0200

    avcodec/svq1dec: Check input space for minimum
    
    We reject inputs that are significantly smaller than the smallest frame.
    This check raises the minimum input needed before time consuming 
computations are performed
    it thus improves the computation per input byte and reduces the potential 
DoS impact
    
    Fixes: Timeout
    Fixes: 
472769364/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SVQ1_DEC_fuzzer-5519737145851904
    
    Found-by: continuous fuzzing process 
https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
    Signed-off-by: Michael Niedermayer <[email protected]>
    (cherry picked from commit d538a71ad52404662d986ec9921b6bc53d353e7f)
    Signed-off-by: Michael Niedermayer <[email protected]>
---
 libavcodec/svq1dec.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavcodec/svq1dec.c b/libavcodec/svq1dec.c
index d6b6bec72d..da79985181 100644
--- a/libavcodec/svq1dec.c
+++ b/libavcodec/svq1dec.c
@@ -680,6 +680,11 @@ static int svq1_decode_frame(AVCodecContext *avctx, void 
*data,
         avctx->skip_frame >= AVDISCARD_ALL)
         return buf_size;
 
+    // Reject obviously too-small packets early: require at least one 
remaining bit per aligned luma macroblock.
+    // FFALIGN(s->width,  16) * FFALIGN(s->height, 16) / 256 represent the 
number of Macroblocks
+    if (get_bits_left(&s->gb) < FFALIGN(s->width,  16) * FFALIGN(s->height, 
16) / 256)
+        return AVERROR_INVALIDDATA;
+
     result = ff_get_buffer(avctx, cur, s->nonref ? 0 : AV_GET_BUFFER_FLAG_REF);
     if (result < 0)
         return result;

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