summaryrefslogtreecommitdiffstats
path: root/patches/source/xorg-server/patch/xorg-server/0004-dix-integer-overflow-in-RegionSizeof-CVE-2014-8092-3.patch
blob: 8023f93ebacd25b20b12f798ddb9090db8f5133d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
From 8f82f69e9e4b76b01b9f5fe06d1ea86851d951c4 Mon Sep 17 00:00:00 2001
From: Alan Coopersmith <alan.coopersmith@oracle.com>
Date: Wed, 22 Jan 2014 22:37:15 -0800
Subject: [PATCH 04/31] dix: integer overflow in RegionSizeof() [CVE-2014-8092
 3/4]

RegionSizeof contains several integer overflows if a large length
value is passed in.  Once we fix it to return 0 on overflow, we
also have to fix the callers to handle this error condition

v2: Fixed limit calculation in RegionSizeof as pointed out by jcristau.

Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Julien Cristau <jcristau@debian.org>
Signed-off-by: Fedora X Ninjas <x@fedoraproject.org>
---
 dix/region.c        | 20 +++++++++++++-------
 include/regionstr.h | 10 +++++++---
 2 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/dix/region.c b/dix/region.c
index 737d2a8..76c4e29 100644
--- a/dix/region.c
+++ b/dix/region.c
@@ -169,7 +169,6 @@ Equipment Corporation.
         ((r1)->y1 <= (r2)->y1) && \
         ((r1)->y2 >= (r2)->y2) )
 
-#define xallocData(n) malloc(RegionSizeof(n))
 #define xfreeData(reg) if ((reg)->data && (reg)->data->size) free((reg)->data)
 
 #define RECTALLOC_BAIL(pReg,n,bail) \
@@ -205,8 +204,9 @@ if (!(pReg)->data || (((pReg)->data->numRects + (n)) > (pReg)->data->size)) \
 #define DOWNSIZE(reg,numRects)						 \
 if (((numRects) < ((reg)->data->size >> 1)) && ((reg)->data->size > 50)) \
 {									 \
-    RegDataPtr NewData;							 \
-    NewData = (RegDataPtr)realloc((reg)->data, RegionSizeof(numRects));	 \
+    size_t NewSize = RegionSizeof(numRects);				 \
+    RegDataPtr NewData =						 \
+        (NewSize > 0) ? realloc((reg)->data, NewSize) : NULL ;		 \
     if (NewData)							 \
     {									 \
 	NewData->size = (numRects);					 \
@@ -330,17 +330,20 @@ Bool
 RegionRectAlloc(RegionPtr pRgn, int n)
 {
     RegDataPtr data;
+    size_t rgnSize;
 
     if (!pRgn->data) {
         n++;
-        pRgn->data = xallocData(n);
+        rgnSize = RegionSizeof(n);
+        pRgn->data = (rgnSize > 0) ? malloc(rgnSize) : NULL;
         if (!pRgn->data)
             return RegionBreak(pRgn);
         pRgn->data->numRects = 1;
         *RegionBoxptr(pRgn) = pRgn->extents;
     }
     else if (!pRgn->data->size) {
-        pRgn->data = xallocData(n);
+        rgnSize = RegionSizeof(n);
+        pRgn->data = (rgnSize > 0) ? malloc(rgnSize) : NULL;
         if (!pRgn->data)
             return RegionBreak(pRgn);
         pRgn->data->numRects = 0;
@@ -352,7 +355,8 @@ RegionRectAlloc(RegionPtr pRgn, int n)
                 n = 250;
         }
         n += pRgn->data->numRects;
-        data = (RegDataPtr) realloc(pRgn->data, RegionSizeof(n));
+        rgnSize = RegionSizeof(n);
+        data = (rgnSize > 0) ? realloc(pRgn->data, rgnSize) : NULL;
         if (!data)
             return RegionBreak(pRgn);
         pRgn->data = data;
@@ -1297,6 +1301,7 @@ RegionFromRects(int nrects, xRectangle *prect, int ctype)
 {
 
     RegionPtr pRgn;
+    size_t rgnSize;
     RegDataPtr pData;
     BoxPtr pBox;
     int i;
@@ -1323,7 +1328,8 @@ RegionFromRects(int nrects, xRectangle *prect, int ctype)
         }
         return pRgn;
     }
-    pData = xallocData(nrects);
+    rgnSize = RegionSizeof(nrects);
+    pData = (rgnSize > 0) ? malloc(rgnSize) : NULL;
     if (!pData) {
         RegionBreak(pRgn);
         return pRgn;
diff --git a/include/regionstr.h b/include/regionstr.h
index 805257b..5006207 100644
--- a/include/regionstr.h
+++ b/include/regionstr.h
@@ -127,7 +127,10 @@ RegionEnd(RegionPtr reg)
 static inline size_t
 RegionSizeof(int n)
 {
-    return (sizeof(RegDataRec) + ((n) * sizeof(BoxRec)));
+    if (n < ((INT_MAX - sizeof(RegDataRec)) / sizeof(BoxRec)))
+        return (sizeof(RegDataRec) + ((n) * sizeof(BoxRec)));
+    else
+        return 0;
 }
 
 static inline void
@@ -138,9 +141,10 @@ RegionInit(RegionPtr _pReg, BoxPtr _rect, int _size)
         (_pReg)->data = (RegDataPtr) NULL;
     }
     else {
+        size_t rgnSize;
         (_pReg)->extents = RegionEmptyBox;
-        if (((_size) > 1) && ((_pReg)->data =
-                              (RegDataPtr) malloc(RegionSizeof(_size)))) {
+        if (((_size) > 1) && ((rgnSize = RegionSizeof(_size)) > 0) &&
+            (((_pReg)->data = malloc(rgnSize)) != NULL)) {
             (_pReg)->data->size = (_size);
             (_pReg)->data->numRects = 0;
         }
-- 
1.9.3