Fix memwipe() of leading unaligned bytes

diff --git a/src/libstrongswan/utils.h b/src/libstrongswan/utils.h
index a334954..bef6f66 100644 (file)
--- a/src/libstrongswan/utils.h
+++ b/src/libstrongswan/utils.h
@@ -347,17 +347,20 @@ void memwipe_noinline(void *ptr, size_t n);
 static inline void memwipe_inline(void *ptr, size_t n)
 {
        volatile char *c = (volatile char*)ptr;
-       int m, i;
+       size_t m, i;
 
        /* byte wise until long aligned */
-       for (i = 0; (uintptr_t)&c % sizeof(long) && i < n; i++)
+       for (i = 0; (uintptr_t)&c[i] % sizeof(long) && i < n; i++)
        {
                c[i] = 0;
        }
-       /* word wize */
-       for (m = n - sizeof(long); i <= m; i += sizeof(long))
+       /* word wise */
+       if (n >= sizeof(long))
        {
-               *(volatile long*)&c[i] = 0;
+               for (m = n - sizeof(long); i <= m; i += sizeof(long))
+               {
+                       *(volatile long*)&c[i] = 0;
+               }
        }
        /* byte wise of the rest */
        for (; i < n; i++)