Intercept fortified recvfrom in socket monitor fault tests

tests/Makefile.am

@@ -284,7 +284,7 @@ test_socket_monitor_LDFLAGS = -Wl,--wrap=socket -Wl,--wrap=bind -Wl,--wrap=close
     -Wl,--wrap=get_interface_ip_by_index -Wl,--wrap=get_interface_ipv6_addr_nl \
     -Wl,--wrap=get_default_route_netif_index -Wl,--wrap=get_outgoing_local_ip -Wl,--wrap=etcp_socket_cbk_fire
 if OS_LINUX
-test_socket_monitor_LDFLAGS += -Wl,--wrap=recvfrom
+test_socket_monitor_LDFLAGS += -Wl,--wrap=recvfrom -Wl,--wrap=__recvfrom_chk
 else
 test_socket_monitor_LDFLAGS += -Wl,--wrap=read
 endif

tests/test_socket_monitor.c

@@ -123,6 +123,12 @@ ssize_t __wrap_recvfrom(int fd, void* out, size_t cap, int flags, struct sockadd
     memset(address, 0, sizeof(struct sockaddr_nl)); *address_size = sizeof(struct sockaddr_nl);
     size_t len = event_length; memcpy(out, event, len); event_length = 0; return (ssize_t)len;
 }
+/* При -Og glibc FORTIFY оставляет checked-вызов вместо прямого recvfrom. */
+ssize_t __wrap___recvfrom_chk(int fd, void* out, size_t cap, size_t object_size, int flags,
+    struct sockaddr* address, socklen_t* address_size) {
+    assert(cap <= object_size);
+    return __wrap_recvfrom(fd, out, cap, flags, address, address_size);
+}
 static void fire_event(int status, unsigned index) {
     struct nlmsghdr* header = (struct nlmsghdr*)event;
     memset(event, 0, sizeof(event));