[FFmpeg-devel] [PATCH] avcodec/scpr3: Clear clr (PR #20188)

[Michael Niedermayer]

PR #20188 opened by Michael Niedermayer (michaelni)
URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20188
Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20188.patch

clr is passing into decode_run_p() its not used when not set
but this possibly triggers msan (it doesnt locally)

Fixes?: use of uninintialized memory
Fixes?: 436997807/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SCPR_fuzzer-6253316466606080

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>


From 670f61dbe510aaf13c8a316a6773a67b9b3d521a Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael at niedermayer.cc>
Date: Fri, 8 Aug 2025 23:19:03 +0200
Subject: [PATCH] avcodec/scpr3: Clear clr

clr is passing into decode_run_p() its not used when not set
but this possibly triggers msan (it doesnt locally)

Fixes?: use of uninintialized memory
Fixes?: 436997807/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SCPR_fuzzer-6253316466606080

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/scpr3.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/scpr3.c b/libavcodec/scpr3.c
index e91c198308..369d2653c2 100644
--- a/libavcodec/scpr3.c
+++ b/libavcodec/scpr3.c
@@ -1167,7 +1167,7 @@ static int decompress_p3(AVCodecContext *avctx,
                 }
             } else {
                 int run, bx = x * 16 + sx1, by = y * 16 + sy1;
-                uint32_t clr, ptype = 0, r, g, b;
+                uint32_t clr = 0, ptype = 0, r, g, b;
 
                 if (bx >= avctx->width)
                     return AVERROR_INVALIDDATA;
-- 
2.49.1