virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00
Code Issues Releases Activity

huffyuv: add padding to classic (v1) huffman tables.

Browse Source 
We slightly overread the input buffer, so we require
padding at the end of the buffer, as is documented in the
get_bits API. Without padding, we'll read uninitialized
data or beyond the end of the .rodata, which may crash.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
This commit is contained in:
Ronald S. Bultje 2012-03-07 16:29:23 -08:00
parent 4c25269ced
commit 4ffe5e2aa5
1 changed files with 6 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
libavcodec/huffyuv.c
View File

@ -82,13 +82,15 @@ typedef struct HYuvContext{
DSPContext dsp;
}HYuvContext;
static const unsigned char classic_shift_luma[] = {
#define classic_shift_luma_table_size 42
static const unsigned char classic_shift_luma[classic_shift_luma_table_size + FF_INPUT_BUFFER_PADDING_SIZE] = {
34,36,35,69,135,232,9,16,10,24,11,23,12,16,13,10,14,8,15,8,
16,8,17,20,16,10,207,206,205,236,11,8,10,21,9,23,8,8,199,70,
69,68, 0
};
static const unsigned char classic_shift_chroma[] = {
#define classic_shift_chroma_table_size 59
static const unsigned char classic_shift_chroma[classic_shift_chroma_table_size + FF_INPUT_BUFFER_PADDING_SIZE] = {
66,36,37,38,39,40,41,75,76,77,110,239,144,81,82,83,84,85,118,183,
56,57,88,89,56,89,154,57,58,57,26,141,57,56,58,57,58,57,184,119,
214,245,116,83,82,49,80,79,78,77,44,75,41,40,39,38,37,36,34, 0
@ -366,10 +368,10 @@ static int read_old_huffman_tables(HYuvContext *s){
GetBitContext gb;
int i;
init_get_bits(&gb, classic_shift_luma, sizeof(classic_shift_luma)*8);
init_get_bits(&gb, classic_shift_luma, classic_shift_luma_table_size*8);
if(read_len_table(s->len[0], &gb)<0)
return -1;
init_get_bits(&gb, classic_shift_chroma, sizeof(classic_shift_chroma)*8);
init_get_bits(&gb, classic_shift_chroma, classic_shift_chroma_table_size*8);
if(read_len_table(s->len[1], &gb)<0)
return -1;