virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2025-04-08 16:54:03 +02:00
Code Issues Releases Activity

avcodec/jpeglsdec: Don't presume the context to contain a JLSState

Browse Source 
Before 9b3c46a081a9f01559082bf7a154fc6be1e06c18 every call to
ff_jpegls_decode_picture() allocated and freed a JLSState. This commit
instead put said structure into the context of the JPEG-LS decoder to
avoid said allocation. But said function can also be called from other
MJPEG-based decoders and their contexts doesn't contain said structure,
leading to segfaults. This commit fixes this: The JLSState is now
allocated on the first call to ff_jpegls_decode_picture() and stored in
the context.

Found-by: Michael Niedermayer <michael@niedermayer.cc>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This commit is contained in:
Andreas Rheinhardt 2021-04-20 18:18:36 +02:00
parent f40e9b1355
commit 718e03e5f2
3 changed files with 12 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
libavcodec/jpeglsdec.c
View File

@ -45,11 +45,6 @@
*/
//#define JLS_BROKEN
typedef struct JpegLSDecodeContext {
MJpegDecodeContext mjpeg;
JLSState state;
} JpegLSDecodeContext;
/**
* Decode LSE block with initialization parameters
*/
@ -355,10 +350,16 @@ int ff_jpegls_decode_picture(MJpegDecodeContext *s, int near,
{
int i, t = 0;
uint8_t *zero, *last, *cur;
JLSState *const state = &((JpegLSDecodeContext*)s)->state;
JLSState *state = s->jls_state;
int off = 0, stride = 1, width, shift, ret = 0;
int decoded_height = 0;
if (!state) {
state = av_malloc(sizeof(*state));
if (!state)
return AVERROR(ENOMEM);
s->jls_state = state;
}
zero = av_mallocz(s->picture_ptr->linesize[0]);
if (!zero)
return AVERROR(ENOMEM);
@ -548,7 +549,7 @@ AVCodec ff_jpegls_decoder = {
.long_name = NULL_IF_CONFIG_SMALL("JPEG-LS"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_JPEGLS,
.priv_data_size = sizeof(JpegLSDecodeContext),
.priv_data_size = sizeof(MJpegDecodeContext),
.init = ff_mjpeg_decode_init,
.close = ff_mjpeg_decode_end,
.receive_frame = ff_mjpeg_receive_frame,

1
libavcodec/mjpegdec.c
View File

@ -2916,6 +2916,7 @@ av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)
reset_icc_profile(s);
av_freep(&s->hwaccel_picture_private);
av_freep(&s->jls_state);
return 0;
}

3
libavcodec/mjpegdec.h
View File

@ -49,6 +49,8 @@ typedef struct ICCEntry {
int length;
} ICCEntry;
struct JLSState;
typedef struct MJpegDecodeContext {
AVClass *class;
AVCodecContext *avctx;
@ -163,6 +165,7 @@ typedef struct MJpegDecodeContext {
enum AVPixelFormat hwaccel_sw_pix_fmt;
enum AVPixelFormat hwaccel_pix_fmt;
void *hwaccel_picture_private;
struct JLSState *jls_state;
} MJpegDecodeContext;
int ff_mjpeg_build_vlc(VLC *vlc, const uint8_t *bits_table,