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| author | Michael Niedermayer <michaelni@gmx.at> | 2013-08-22 01:07:32 +0200 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2013-08-29 01:29:35 +0200 |
| commit | 7549bcb295f04071dcbfc7a412e0618fb38dd8a3 (patch) | |
| tree | 14b09759c436b183fc1c8b24c52ea40e03cfcf32 | |
| parent | 65753697efdb9e4dd61f4ba582bd04476acdc69a (diff) | |
| download | ffmpeg-7549bcb295f04071dcbfc7a412e0618fb38dd8a3.tar.gz | |
avcodec/rpza: Perform pointer advance and checks before using the pointers
Fixes out of array accesses
Fixes Ticket2850
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 3819db745da2ac7fb3faacb116788c32f4753f34)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
| -rw-r--r-- | libavcodec/rpza.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/libavcodec/rpza.c b/libavcodec/rpza.c index b12bf04fa2..d37990aa74 100644 --- a/libavcodec/rpza.c +++ b/libavcodec/rpza.c @@ -84,7 +84,7 @@ static void rpza_decode_stream(RpzaContext *s) unsigned short *pixels = (unsigned short *)s->frame.data[0]; int row_ptr = 0; - int pixel_ptr = 0; + int pixel_ptr = -4; int block_ptr; int pixel_x, pixel_y; int total_blocks; @@ -140,6 +140,7 @@ static void rpza_decode_stream(RpzaContext *s) colorA = AV_RB16 (&s->buf[stream_ptr]); stream_ptr += 2; while (n_blocks--) { + ADVANCE_BLOCK() block_ptr = row_ptr + pixel_ptr; for (pixel_y = 0; pixel_y < 4; pixel_y++) { for (pixel_x = 0; pixel_x < 4; pixel_x++){ @@ -148,7 +149,6 @@ static void rpza_decode_stream(RpzaContext *s) } block_ptr += row_inc; } - ADVANCE_BLOCK(); } break; @@ -187,6 +187,7 @@ static void rpza_decode_stream(RpzaContext *s) if (s->size - stream_ptr < n_blocks * 4) return; while (n_blocks--) { + ADVANCE_BLOCK(); block_ptr = row_ptr + pixel_ptr; for (pixel_y = 0; pixel_y < 4; pixel_y++) { index = s->buf[stream_ptr++]; @@ -197,7 +198,6 @@ static void rpza_decode_stream(RpzaContext *s) } block_ptr += row_inc; } - ADVANCE_BLOCK(); } break; @@ -205,6 +205,7 @@ static void rpza_decode_stream(RpzaContext *s) case 0x00: if (s->size - stream_ptr < 16) return; + ADVANCE_BLOCK(); block_ptr = row_ptr + pixel_ptr; for (pixel_y = 0; pixel_y < 4; pixel_y++) { for (pixel_x = 0; pixel_x < 4; pixel_x++){ @@ -218,7 +219,6 @@ static void rpza_decode_stream(RpzaContext *s) } block_ptr += row_inc; } - ADVANCE_BLOCK(); break; /* Unknown opcode */ |