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
|
Description: [CVE-2021-26937] Fix out of bounds array access
Author: Michael Schröder <mls@suse.de>
Bug-Debian: https://bugs.debian.org/982435
Bug: https://savannah.gnu.org/bugs/?60030
Bug: https://lists.gnu.org/archive/html/screen-devel/2021-02/msg00000.html
Bug-OSS-Security: https://www.openwall.com/lists/oss-security/2021/02/09/3
Origin: https://lists.gnu.org/archive/html/screen-devel/2021-02/msg00010.html
CVE: CVE-2021-26937
Upstream-Status: Pending
Signed-off-by: Scott Murray <scott.murray@konsulko.com>
--- a/encoding.c
+++ b/encoding.c
@@ -43,7 +43,7 @@
# ifdef UTF8
static int recode_char __P((int, int, int));
static int recode_char_to_encoding __P((int, int));
-static void comb_tofront __P((int, int));
+static void comb_tofront __P((int));
# ifdef DW_CHARS
static int recode_char_dw __P((int, int *, int, int));
static int recode_char_dw_to_encoding __P((int, int *, int));
@@ -1263,6 +1263,8 @@
{0x30000, 0x3FFFD},
};
+ if (c >= 0xdf00 && c <= 0xdfff)
+ return 1; /* dw combining sequence */
return ((bisearch(c, wide, sizeof(wide) / sizeof(struct interval) - 1)) ||
(cjkwidth &&
bisearch(c, ambiguous,
@@ -1330,11 +1332,12 @@
}
static void
-comb_tofront(root, i)
-int root, i;
+comb_tofront(i)
+int i;
{
for (;;)
{
+ int root = i >= 0x700 ? 0x801 : 0x800;
debug1("bring to front: %x\n", i);
combchars[combchars[i]->prev]->next = combchars[i]->next;
combchars[combchars[i]->next]->prev = combchars[i]->prev;
@@ -1396,9 +1399,9 @@
{
/* full, recycle old entry */
if (c1 >= 0xd800 && c1 < 0xe000)
- comb_tofront(root, c1 - 0xd800);
+ comb_tofront(c1 - 0xd800);
i = combchars[root]->prev;
- if (c1 == i + 0xd800)
+ if (i == 0x800 || i == 0x801 || c1 == i + 0xd800)
{
/* completely full, can't recycle */
debug("utf8_handle_comp: completely full!\n");
@@ -1422,7 +1425,7 @@
mc->font = (i >> 8) + 0xd8;
mc->fontx = 0;
debug3("combinig char %x %x -> %x\n", c1, c, i + 0xd800);
- comb_tofront(root, i);
+ comb_tofront(i);
}
#else /* !UTF8 */
|
