From 997a997465b5848bfa8437345fef67c81ccfd387 Mon Sep 17 00:00:00 2001 From: Andreas Cadhalpun Date: Thu, 16 Apr 2015 21:25:26 +0200 Subject: ac3: validate end in ff_ac3_bit_alloc_calc_mask This fixes an invalid read if end is 0: band_end = ff_ac3_bin_to_band_tab[end-1] + 1; Depending on what is before the array, this can cause stack smashing, when band_end becomes too large. Signed-off-by: Andreas Cadhalpun Signed-off-by: Michael Niedermayer (cherry picked from commit bc4fee7f2a51635fa3c0f61d1e5164da1efeded3) Signed-off-by: Michael Niedermayer --- libavcodec/ac3.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavcodec/ac3.c b/libavcodec/ac3.c index 29e132f5d1..8d39bbe83b 100644 --- a/libavcodec/ac3.c +++ b/libavcodec/ac3.c @@ -131,6 +131,9 @@ int ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *band_psd, int band_start, band_end, begin, end1; int lowcomp, fastleak, slowleak; + if (end <= 0) + return AVERROR_INVALIDDATA; + /* excitation function */ band_start = ff_ac3_bin_to_band_tab[start]; band_end = ff_ac3_bin_to_band_tab[end-1] + 1; -- cgit v1.2.1