openwrt/toolchain/musl/patches/700-wcsnrtombs-cve-2020-289...

64 lines
1.2 KiB
Diff

--- a/src/multibyte/wcsnrtombs.c
+++ b/src/multibyte/wcsnrtombs.c
@@ -1,41 +1,33 @@
#include <wchar.h>
+#include <limits.h>
+#include <string.h>
size_t wcsnrtombs(char *restrict dst, const wchar_t **restrict wcs, size_t wn, size_t n, mbstate_t *restrict st)
{
- size_t l, cnt=0, n2;
- char *s, buf[256];
const wchar_t *ws = *wcs;
- const wchar_t *tmp_ws;
-
- if (!dst) s = buf, n = sizeof buf;
- else s = dst;
-
- while ( ws && n && ( (n2=wn)>=n || n2>32 ) ) {
- if (n2>=n) n2=n;
- tmp_ws = ws;
- l = wcsrtombs(s, &ws, n2, 0);
- if (!(l+1)) {
- cnt = l;
- n = 0;
+ size_t cnt = 0;
+ if (!dst) n=0;
+ while (ws && wn) {
+ char tmp[MB_LEN_MAX];
+ size_t l = wcrtomb(n<MB_LEN_MAX ? tmp : dst, *ws, 0);
+ if (l==-1) {
+ cnt = -1;
break;
}
- if (s != buf) {
- s += l;
+ if (dst) {
+ if (n<MB_LEN_MAX) {
+ if (l>n) break;
+ memcpy(dst, tmp, l);
+ }
+ dst += l;
n -= l;
}
- wn = ws ? wn - (ws - tmp_ws) : 0;
- cnt += l;
- }
- if (ws) while (n && wn) {
- l = wcrtomb(s, *ws, 0);
- if ((l+1)<=1) {
- if (!l) ws = 0;
- else cnt = l;
+ if (!*ws) {
+ ws = 0;
break;
}
- ws++; wn--;
- /* safe - this loop runs fewer than sizeof(buf) times */
- s+=l; n-=l;
+ ws++;
+ wn--;
cnt += l;
}
if (dst) *wcs = ws;