Add recv() checks

1 files changed, 31 insertions, 0 deletions

diff --git a/include/sys/socket.h b/include/sys/socket.h
new file mode 100644
index 0000000..df15961
--- /dev/null
+++ b/include/sys/socket.h
@@ -0,0 +1,31 @@
+/* See LICENSE file for copyright and license details. */
+#ifndef FORTIFY_SYS_SOCKET_H_
+#define FORTIFY_SYS_SOCKET_H_
+
+#include_next <sys/socket.h>
+
+#if defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0 && defined(__OPTIMIZE__) && __OPTIMIZE__ > 0
+
+#define __errordecl(name, msg) extern void name(void) __attribute__((__error__(msg)))
+
+__errordecl(__recv_error, "recv: buffer overflow detected");
+static inline __attribute__ ((always_inline))
+ssize_t
+__fortify_recv(int sockfd, void *buf, size_t n, int flags)
+{
+        size_t bos = __builtin_object_size(buf, 0);
+
+        if (__builtin_constant_p(n) && n > bos)
+                __recv_error();
+
+        if (n > bos)
+                __builtin_trap();
+        return recv(sockfd, buf, n, flags);
+}
+
+#undef recv
+#define recv(sockfd, buf, n, flags) __fortify_recv(sockfd, buf, n, flags)
+
+#endif
+
+#endif