This is an automated email from the git hooks/post-receive script.
Git pushed a commit to branch master
in repository ffmpeg.
The following commit(s) were added to refs/heads/master by this push:
new 11ff18a6c8 avcodec/rasc: Check that 32-bit DLTA accesses stay within
the row
11ff18a6c8 is described below
commit 11ff18a6c80187405fc492f9bb07ba9f2f663f76
Author: Umar Pathan <[email protected]>
AuthorDate: Sun Jun 28 23:02:52 2026 +0200
Commit: michaelni <[email protected]>
CommitDate: Sun Jun 28 21:52:21 2026 +0000
avcodec/rasc: Check that 32-bit DLTA accesses stay within the row
Found-by: bikini (github.com/bikini/exploitarium)
Fixes: out of array access
Fixes: rowspill_128x1.avi / gen_rowspill_avi.py
Fixes: xGV79bIb7uAJ
---
libavcodec/rasc.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/libavcodec/rasc.c b/libavcodec/rasc.c
index 5f956a9b2c..d784a44063 100644
--- a/libavcodec/rasc.c
+++ b/libavcodec/rasc.c
@@ -320,6 +320,11 @@ static int decode_move(AVCodecContext *avctx,
return 0;
}
+static inline int dlta_room(unsigned cx, unsigned w, unsigned bpp, unsigned
need)
+{
+ return cx + need <= w * bpp;
+}
+
#define NEXT_LINE \
if (cx >= w * s->bpp) { \
cx = 0; \
@@ -418,6 +423,8 @@ static int decode_dlta(AVCodecContext *avctx,
case 4:
fill = bytestream2_get_byte(&dc);
while (len > 0 && cy > 0) {
+ if (!dlta_room(cx, w, s->bpp, 4))
+ return AVERROR_INVALIDDATA;
AV_WL32(b1 + cx, AV_RL32(b2 + cx));
AV_WL32(b2 + cx, fill);
cx++;
@@ -427,6 +434,8 @@ static int decode_dlta(AVCodecContext *avctx,
case 7:
fill = bytestream2_get_le32(&dc);
while (len > 0 && cy > 0) {
+ if (!dlta_room(cx, w, s->bpp, 4))
+ return AVERROR_INVALIDDATA;
AV_WL32(b1 + cx, AV_RL32(b2 + cx));
AV_WL32(b2 + cx, fill);
cx += 4;
@@ -443,6 +452,8 @@ static int decode_dlta(AVCodecContext *avctx,
while (len > 0 && cy > 0) {
unsigned v0, v1;
+ if (!dlta_room(cx, w, s->bpp, 4))
+ return AVERROR_INVALIDDATA;
v0 = AV_RL32(b2 + cx);
v1 = AV_RL32(b1 + cx);
AV_WL32(b2 + cx, v1);
@@ -454,6 +465,8 @@ static int decode_dlta(AVCodecContext *avctx,
case 13:
while (len > 0 && cy > 0) {
fill = bytestream2_get_le32(&dc);
+ if (!dlta_room(cx, w, s->bpp, 4))
+ return AVERROR_INVALIDDATA;
AV_WL32(b1 + cx, AV_RL32(b2 + cx));
AV_WL32(b2 + cx, fill);
cx += 4;
_______________________________________________
ffmpeg-cvslog mailing list -- [email protected]
To unsubscribe send an email to [email protected]
