From cc8b8889056fd6a7a70a7fa13904aae22a5e8493 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 1 May 2024 22:33:14 +0200 Subject: [PATCH] avcodec/cbs_jpeg: Try to move the read entity to one side in a test The checked entity should be alone on one side of the check, this avoids complex considerations of overflows. This fixes a issue of bad style in our code and a coverity issue. Fixes: CID1439654 Untrusted pointer read Sponsored-by: Sovereign Tech Fund Signed-off-by: Michael Niedermayer (cherry picked from commit 385784a148d2886884aac69acc31bf179fac3ac2) Signed-off-by: Michael Niedermayer --- libavcodec/cbs_jpeg.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/cbs_jpeg.c b/libavcodec/cbs_jpeg.c index 471d77074f..3ce464c86b 100644 --- a/libavcodec/cbs_jpeg.c +++ b/libavcodec/cbs_jpeg.c @@ -166,13 +166,13 @@ static int cbs_jpeg_split_fragment(CodedBitstreamContext *ctx, } } else { i = start; - if (i + 2 > frag->data_size) { + if (i > frag->data_size - 2) { av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid JPEG image: " "truncated at %02x marker.\n", marker); return AVERROR_INVALIDDATA; } length = AV_RB16(frag->data + i); - if (i + length > frag->data_size) { + if (length > frag->data_size - i) { av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid JPEG image: " "truncated at %02x marker segment.\n", marker); return AVERROR_INVALIDDATA;