From d495747a9fc5fb8dcac4b23c5bdca3c5c16dd152 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 20 Feb 2023 19:53:19 +0100 Subject: [PATCH] avcodec/rka: Fix some integer anomalies Fixes: left shift of negative value -3201 Fixes: integer overflow: -76470276 * -25608 cannot be represented in type 'int' Fixes: 56052/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_RKA_fuzzer-5236218750435328 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/rka.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/libavcodec/rka.c b/libavcodec/rka.c index 461baf1e1f..994c563ffd 100644 --- a/libavcodec/rka.c +++ b/libavcodec/rka.c @@ -723,16 +723,16 @@ static int decode_filter(RKAContext *s, ChContext *ctx, ACoder *ac, int off, uns last_val = val; src = &ctx->buf1[off + -1]; for (int i = 0; i < filt.size && i < 15; i++) - sum += filt.coeffs[i] * src[-i]; + sum += filt.coeffs[i] * (unsigned)src[-i]; sum = sum * 2; for (int i = 15; i < filt.size; i++) - sum += filt.coeffs[i] * src[-i]; + sum += filt.coeffs[i] * (unsigned)src[-i]; sum = sum >> 6; if (ctx->cmode == 0) { if (bits == 0) { ctx->buf1[off] = sum + val; } else { - ctx->buf1[off] = (val + (sum >> bits) << bits) + + ctx->buf1[off] = (val + (sum >> bits)) * (1 << bits) + (((1U << bits) - 1U) & ctx->buf1[off + -1]); } ctx->buf0[off] = ctx->buf1[off] + ctx->buf0[off + -1];