From ae3d6a337ad25527bcd3172e3885e45fadf9908c Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 8 Aug 2019 19:48:19 +0200 Subject: [PATCH] avcodec/alac: Fix multiple integer overflows in lpc_prediction() Fixes: signed integer overflow: 2088795537 + 2147254401 cannot be represented in type 'int' Fixes: signed integer overflow: -1500363496 + -1295351808 cannot be represented in type 'int' Fixes: signed integer overflow: -79560 * 32640 cannot be represented in type 'int' Fixes: signed integer overflow: 2088910005 + 2088796058 cannot be represented in type 'int' Fixes: signed integer overflow: -117258064 - 2088725225 cannot be represented in type 'int' Fixes: signed integer overflow: 2088725225 - -117258064 cannot be represented in type 'int' Fixes: 15739/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALAC_fuzzer-5630664122040320 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/alac.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/libavcodec/alac.c b/libavcodec/alac.c index c234d7153b..6086e2caa8 100644 --- a/libavcodec/alac.c +++ b/libavcodec/alac.c @@ -171,12 +171,12 @@ static inline int sign_only(int v) return v ? FFSIGN(v) : 0; } -static void lpc_prediction(int32_t *error_buffer, int32_t *buffer_out, +static void lpc_prediction(int32_t *error_buffer, uint32_t *buffer_out, int nb_samples, int bps, int16_t *lpc_coefs, int lpc_order, int lpc_quant) { int i; - int32_t *pred = buffer_out; + uint32_t *pred = buffer_out; /* first sample always copies */ *buffer_out = *error_buffer; @@ -208,7 +208,7 @@ static void lpc_prediction(int32_t *error_buffer, int32_t *buffer_out, for (; i < nb_samples; i++) { int j; int val = 0; - int error_val = error_buffer[i]; + unsigned error_val = error_buffer[i]; int error_sign; int d = *pred++; @@ -222,7 +222,7 @@ static void lpc_prediction(int32_t *error_buffer, int32_t *buffer_out, /* adapt LPC coefficients */ error_sign = sign_only(error_val); if (error_sign) { - for (j = 0; j < lpc_order && error_val * error_sign > 0; j++) { + for (j = 0; j < lpc_order && (int)error_val * error_sign > 0; j++) { int sign; val = d - pred[j]; sign = sign_only(val) * error_sign;