hivex: fail upon integer overflow

* hivex/hivex.c (windows_utf16_to_utf8): Avoid overflow and a
potential infloop.

diff --git a/hivex/hivex.c b/hivex/hivex.c
index 4fa3b30..ac46346 100644 (file)
--- a/hivex/hivex.c
+++ b/hivex/hivex.c
@@ -1033,9 +1033,12 @@ windows_utf16_to_utf8 (/* const */ char *input, size_t len)
   size_t r = iconv (ic, &inp, &inlen, &outp, &outlen);
   if (r == (size_t) -1) {
     if (errno == E2BIG) {
   size_t r = iconv (ic, &inp, &inlen, &outp, &outlen);
   if (r == (size_t) -1) {
     if (errno == E2BIG) {

+      size_t prev = outalloc;

       /* Try again with a larger output buffer. */
       free (out);
       outalloc *= 2;
       /* Try again with a larger output buffer. */
       free (out);
       outalloc *= 2;

+      if (outalloc < prev)
+        return NULL;

       goto again;
     }
     else {
       goto again;
     }
     else {