From e22b12e3040dca09d212da3bc3e92595449549be Mon Sep 17 00:00:00 2001
From: Yaowu Xu <yaowu@google.com>
Date: Sat, 22 Feb 2014 12:30:18 -0800
Subject: [PATCH] Added clamp of qindex to valid range
The qindex for a segment was not clamped in ABSDATA mode, which may
cause invalid memory access if an ill-formed stream has a negative
value in ABSDATA mode. This commit added clamp to make sure qindex
for a segment always fall into valid range.
Change-Id: I0a74d00f4ef40aec7edaeca1d03c8645e23ab08c
---
vp9/common/vp9_quant_common.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/vp9/common/vp9_quant_common.c b/vp9/common/vp9_quant_common.c
index 9fef8b1ef4..def12554df 100644
--- a/vp9/common/vp9_quant_common.c
+++ b/vp9/common/vp9_quant_common.c
@@ -134,9 +134,9 @@ int vp9_get_qindex(const struct segmentation *seg, int segment_id,
int base_qindex) {
if (vp9_segfeature_active(seg, segment_id, SEG_LVL_ALT_Q)) {
const int data = vp9_get_segdata(seg, segment_id, SEG_LVL_ALT_Q);
- return seg->abs_delta == SEGMENT_ABSDATA ?
- data : // Abs value
- clamp(base_qindex + data, 0, MAXQ); // Delta value
+ const int seg_qindex = seg->abs_delta == SEGMENT_ABSDATA ?
+ data : base_qindex + data;
+ return clamp(seg_qindex, 0, MAXQ);
} else {
return base_qindex;
}
--
GitLab