getservbyport_r: fix out-of-bounds buffer read

[musl] / src / string / stpncpy.c

diff --git a/src/string/stpncpy.c b/src/string/stpncpy.c
index a04cdce..f57fa6b 100644 (file)
--- a/src/string/stpncpy.c
+++ b/src/string/stpncpy.c
@@ -1,19 +1,18 @@
 #include <string.h>
-#include <stdlib.h>
 #include <stdint.h>
 #include <limits.h>
-#include "libc.h"
 
 #define ALIGN (sizeof(size_t)-1)
 #define ONES ((size_t)-1/UCHAR_MAX)
 #define HIGHS (ONES * (UCHAR_MAX/2+1))
 #define HASZERO(x) ((x)-ONES & ~(x) & HIGHS)
 
-char *__stpncpy(char *d, const char *s, size_t n)
+char *__stpncpy(char *restrict d, const char *restrict s, size_t n)
 {
-       size_t *wd;
-       const size_t *ws;
-
+#ifdef __GNUC__
+       typedef size_t __attribute__((__may_alias__)) word;
+       word *wd;
+       const word *ws;
        if (((uintptr_t)s & ALIGN) == ((uintptr_t)d & ALIGN)) {
                for (; ((uintptr_t)s & ALIGN) && n && (*d=*s); n--, s++, d++);
                if (!n || !*s) goto tail;
@@ -22,6 +21,7 @@ char *__stpncpy(char *d, const char *s, size_t n)
                       n-=sizeof(size_t), ws++, wd++) *wd = *ws;
                d=(void *)wd; s=(const void *)ws;
        }
+#endif
        for (; n && (*d=*s); n--, s++, d++);
 tail:
        memset(d, 0, n);