upstream commit

Switch to recallocarray() for a few operations.  Both
growth and shrinkage are handled safely, and there also is no need for
preallocation dances. Future changes in this area will be less error prone.
Review and one bug found by markus

Upstream-ID: 822d664d6a5a1d10eccb23acdd53578a679d5065

1 files changed, 8 insertions, 8 deletions

diff --git a/sshbuf.c b/sshbuf.c
index 652c99a21..b7a90b5c2 100644
--- a/sshbuf.c
+++ b/sshbuf.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: sshbuf.c,v 1.9 2017/05/26 20:34:49 markus Exp $       */
+/*      $OpenBSD: sshbuf.c,v 1.10 2017/05/31 09:15:42 deraadt Exp $     */
 /*
  * Copyright (c) 2011 Damien Miller
  *
@@ -193,15 +193,16 @@ sshbuf_reset(struct sshbuf *buf)
                 buf->off = buf->size;
                 return;
         }
-        if (sshbuf_check_sanity(buf) == 0)
-                explicit_bzero(buf->d, buf->alloc);
+        (void) sshbuf_check_sanity(buf);
         buf->off = buf->size = 0;
         if (buf->alloc != SSHBUF_SIZE_INIT) {
-                if ((d = realloc(buf->d, SSHBUF_SIZE_INIT)) != NULL) {
+                if ((d = recallocarray(buf->d, buf->alloc, SSHBUF_SIZE_INIT,
+                    1)) != NULL) {
                         buf->cd = buf->d = d;
                         buf->alloc = SSHBUF_SIZE_INIT;
                 }
-        }
+        } else
+                explicit_bzero(buf->d, SSHBUF_SIZE_INIT);
 }
 
 size_t
@@ -253,9 +254,8 @@ sshbuf_set_max_size(struct sshbuf *buf, size_t max_size)
                         rlen = ROUNDUP(buf->size, SSHBUF_SIZE_INC);
                 if (rlen > max_size)
                         rlen = max_size;
-                explicit_bzero(buf->d + buf->size, buf->alloc - buf->size);
                 SSHBUF_DBG(("new alloc = %zu", rlen));
-                if ((dp = realloc(buf->d, rlen)) == NULL)
+                if ((dp = recallocarray(buf->d, buf->alloc, rlen, 1)) == NULL)
                         return SSH_ERR_ALLOC_FAIL;
                 buf->cd = buf->d = dp;
                 buf->alloc = rlen;
@@ -344,7 +344,7 @@ sshbuf_allocate(struct sshbuf *buf, size_t len)
         if (rlen > buf->max_size)
                 rlen = buf->alloc + need;
         SSHBUF_DBG(("adjusted rlen %zu", rlen));
-        if ((dp = realloc(buf->d, rlen)) == NULL) {
+        if ((dp = recallocarray(buf->d, buf->alloc, rlen, 1)) == NULL) {
                 SSHBUF_DBG(("realloc fail"));
                 return SSH_ERR_ALLOC_FAIL;
         }