[FFmpeg-devel] [PATCH 4/6] avcodec/flicvideo: Make line_packets int

Michael Niedermayer michael at niedermayer.cc
Sat Jun 22 02:29:34 EEST 2019


Fixes: signed integer overflow: -32768 * 196032 cannot be represented in type 'int'
Fixes: 15300/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_FLIC_fuzzer-5733319519502336

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/flicvideo.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/libavcodec/flicvideo.c b/libavcodec/flicvideo.c
index ba5bda48c4..cd9cd089af 100644
--- a/libavcodec/flicvideo.c
+++ b/libavcodec/flicvideo.c
@@ -175,7 +175,7 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
     int lines;
     int compressed_lines;
     int starting_line;
-    signed short line_packets;
+    int line_packets;
     int y_ptr;
     int byte_run;
     int pixel_skip;
@@ -274,7 +274,7 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
                     break;
                 if (y_ptr > pixel_limit)
                     return AVERROR_INVALIDDATA;
-                line_packets = bytestream2_get_le16(&g2);
+                line_packets = (int16_t)bytestream2_get_le16(&g2);
                 if ((line_packets & 0xC000) == 0xC000) {
                     // line skip opcode
                     line_packets = -line_packets;
@@ -340,7 +340,7 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
                 pixel_countdown = s->avctx->width;
                 if (bytestream2_tell(&g2) + 1 > stream_ptr_after_chunk)
                     break;
-                line_packets = bytestream2_get_byte(&g2);
+                line_packets = (int16_t)bytestream2_get_byte(&g2);
                 if (line_packets > 0) {
                     for (i = 0; i < line_packets; i++) {
                         /* account for the skip bytes */
@@ -508,7 +508,7 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
 
     int lines;
     int compressed_lines;
-    signed short line_packets;
+    int line_packets;
     int y_ptr;
     int byte_run;
     int pixel_skip;
@@ -572,7 +572,7 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
                     break;
                 if (y_ptr > pixel_limit)
                     return AVERROR_INVALIDDATA;
-                line_packets = bytestream2_get_le16(&g2);
+                line_packets = (int16_t)bytestream2_get_le16(&g2);
                 if (line_packets < 0) {
                     line_packets = -line_packets;
                     if (line_packets > s->avctx->height)
@@ -806,7 +806,7 @@ static int flic_decode_frame_24BPP(AVCodecContext *avctx,
 
     int lines;
     int compressed_lines;
-    signed short line_packets;
+    int line_packets;
     int y_ptr;
     int byte_run;
     int pixel_skip;
@@ -870,7 +870,7 @@ static int flic_decode_frame_24BPP(AVCodecContext *avctx,
                     break;
                 if (y_ptr > pixel_limit)
                     return AVERROR_INVALIDDATA;
-                line_packets = bytestream2_get_le16(&g2);
+                line_packets = (int16_t)bytestream2_get_le16(&g2);
                 if (line_packets < 0) {
                     line_packets = -line_packets;
                     if (line_packets > s->avctx->height)
-- 
2.22.0



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