videolan
/
ffmpeg
mirror of https://git.videolan.org/git/ffmpeg.git
1
Fork 0
Code Releases Activity

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>
This commit is contained in:
Michael Niedermayer 2013-08-22 01:07:32 +02:00
parent 920046abf1
commit 3819db745d
1 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
libavcodec/rpza.c
View File

@ -85,7 +85,7 @@ 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;
@ -141,6 +141,7 @@ 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++){
@ -149,7 +150,6 @@ static void rpza_decode_stream(RpzaContext *s)
}
block_ptr += row_inc;
}
ADVANCE_BLOCK();
}
break;
@ -188,6 +188,7 @@ 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++];
@ -198,7 +199,6 @@ static void rpza_decode_stream(RpzaContext *s)
}
block_ptr += row_inc;
}
ADVANCE_BLOCK();
}
break;
@ -206,6 +206,7 @@ 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++){
@ -219,7 +220,6 @@ static void rpza_decode_stream(RpzaContext *s)
}
block_ptr += row_inc;
}
ADVANCE_BLOCK();
break;
/* Unknown opcode */