- djm@cvs.openbsd.org 2006/03/25 01:13:23
[buffer.c channels.c deattack.c misc.c scp.c session.c sftp-client.c]
[sftp-server.c ssh-agent.c ssh-rsa.c xmalloc.c xmalloc.h auth-pam.c]
[uidswap.c]
change OpenSSH's xrealloc() function from being xrealloc(p, new_size)
to xrealloc(p, new_nmemb, new_itemsize).
realloc is particularly prone to integer overflows because it is
almost always allocating "n * size" bytes, so this is a far safer
API; ok deraadt@
diff --git a/xmalloc.c b/xmalloc.c
index 6d56781..d5d7b6b 100644
--- a/xmalloc.c
+++ b/xmalloc.c
@@ -35,7 +35,7 @@
{
void *ptr;
- if (nmemb && size && SIZE_T_MAX / nmemb < size)
+ if (nmemb && size && SIZE_T_MAX / nmemb < size)
fatal("xcalloc: nmemb * size > SIZE_T_MAX");
if (size == 0 || nmemb == 0)
fatal("xcalloc: zero size");
@@ -47,10 +47,13 @@
}
void *
-xrealloc(void *ptr, size_t new_size)
+xrealloc(void *ptr, size_t nmemb, size_t size)
{
void *new_ptr;
+ size_t new_size = nmemb * size;
+ if (nmemb && size && SIZE_T_MAX / nmemb < size)
+ fatal("xrealloc: nmemb * size > SIZE_T_MAX");
if (new_size == 0)
fatal("xrealloc: zero size");
if (ptr == NULL)
@@ -58,7 +61,8 @@
else
new_ptr = realloc(ptr, new_size);
if (new_ptr == NULL)
- fatal("xrealloc: out of memory (new_size %lu bytes)", (u_long) new_size);
+ fatal("xrealloc: out of memory (new_size %lu bytes)",
+ (u_long) new_size);
return new_ptr;
}