From 14e4e26559697cfdea584767be4e68474a0a9c7f Mon Sep 17 00:00:00 2001 From: Andreas Cadhalpun Date: Sun, 30 Oct 2016 20:47:22 +0100 Subject: [PATCH] interplayacm: check for too large b This fixes out-of-bounds reads. Reviewed-by: Paul B Mahol Signed-off-by: Andreas Cadhalpun --- libavcodec/interplayacm.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/libavcodec/interplayacm.c b/libavcodec/interplayacm.c index 0fd350167a..0486e00b1e 100644 --- a/libavcodec/interplayacm.c +++ b/libavcodec/interplayacm.c @@ -326,6 +326,10 @@ static int t15(InterplayACMContext *s, unsigned ind, unsigned col) for (i = 0; i < s->rows; i++) { /* b = (x1) + (x2 * 3) + (x3 * 9) */ b = get_bits(gb, 5); + if (b > 26) { + av_log(NULL, AV_LOG_ERROR, "Too large b = %d > 26\n", b); + return AVERROR_INVALIDDATA; + } n1 = (mul_3x3[b] & 0x0F) - 1; n2 = ((mul_3x3[b] >> 4) & 0x0F) - 1; @@ -351,6 +355,10 @@ static int t27(InterplayACMContext *s, unsigned ind, unsigned col) for (i = 0; i < s->rows; i++) { /* b = (x1) + (x2 * 5) + (x3 * 25) */ b = get_bits(gb, 7); + if (b > 124) { + av_log(NULL, AV_LOG_ERROR, "Too large b = %d > 124\n", b); + return AVERROR_INVALIDDATA; + } n1 = (mul_3x5[b] & 0x0F) - 2; n2 = ((mul_3x5[b] >> 4) & 0x0F) - 2; @@ -375,6 +383,10 @@ static int t37(InterplayACMContext *s, unsigned ind, unsigned col) for (i = 0; i < s->rows; i++) { /* b = (x1) + (x2 * 11) */ b = get_bits(gb, 7); + if (b > 120) { + av_log(NULL, AV_LOG_ERROR, "Too large b = %d > 120\n", b); + return AVERROR_INVALIDDATA; + } n1 = (mul_2x11[b] & 0x0F) - 5; n2 = ((mul_2x11[b] >> 4) & 0x0F) - 5;