um: Convert strscpy() usage to 2-argument style

The ARCH=um build has its own idea about strscpy()'s definition. Adjust
the callers to remove the redundant sizeof() arguments ahead of treewide
changes, since it needs a manual adjustment for the newly named
sized_strscpy() export.

Cc: Richard Weinberger <richard@nod.at>
Cc: linux-um@lists.infradead.org
Signed-off-by: Kees Cook <keescook@chromium.org>

arch/um/drivers/net_kern.c

@@ -265,7 +265,7 @@ static void uml_net_poll_controller(struct net_device *dev)
 static void uml_net_get_drvinfo(struct net_device *dev,
 				struct ethtool_drvinfo *info)
 {
-	strscpy(info->driver, DRIVER_NAME, sizeof(info->driver));
+	strscpy(info->driver, DRIVER_NAME);
 }
 
 static const struct ethtool_ops uml_net_ethtool_ops = {

arch/um/drivers/vector_kern.c

@@ -1373,7 +1373,7 @@ static void vector_net_poll_controller(struct net_device *dev)
 static void vector_net_get_drvinfo(struct net_device *dev,
 				struct ethtool_drvinfo *info)
 {
-	strscpy(info->driver, DRIVER_NAME, sizeof(info->driver));
+	strscpy(info->driver, DRIVER_NAME);
 }
 
 static int vector_net_load_bpf_flash(struct net_device *dev,

arch/um/drivers/vector_user.c

@@ -141,7 +141,7 @@ static int create_tap_fd(char *iface)
 	}
 	memset(&ifr, 0, sizeof(ifr));
 	ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR;
-	strscpy(ifr.ifr_name, iface, sizeof(ifr.ifr_name));
+	strscpy(ifr.ifr_name, iface);
 
 	err = ioctl(fd, TUNSETIFF, (void *) &ifr);
 	if (err != 0) {
@@ -171,7 +171,7 @@ static int create_raw_fd(char *iface, int flags, int proto)
 		goto raw_fd_cleanup;
 	}
 	memset(&ifr, 0, sizeof(ifr));
-	strscpy(ifr.ifr_name, iface, sizeof(ifr.ifr_name));
+	strscpy(ifr.ifr_name, iface);
 	if (ioctl(fd, SIOCGIFINDEX, (void *) &ifr) < 0) {
 		err = -errno;
 		goto raw_fd_cleanup;

arch/um/include/shared/user.h

@@ -52,7 +52,7 @@ static inline int printk(const char *fmt, ...)
 extern int in_aton(char *str);
 extern size_t strlcat(char *, const char *, size_t);
 extern size_t sized_strscpy(char *, const char *, size_t);
-#define strscpy(dst, src, size)	sized_strscpy(dst, src, size)
+#define strscpy(dst, src)	sized_strscpy(dst, src, sizeof(dst))
 
 /* Copied from linux/compiler-gcc.h since we can't include it directly */
 #define barrier() __asm__ __volatile__("": : :"memory")

arch/um/os-Linux/drivers/ethertap_user.c

@@ -105,7 +105,7 @@ static int etap_tramp(char *dev, char *gate, int control_me,
 	sprintf(data_fd_buf, "%d", data_remote);
 	sprintf(version_buf, "%d", UML_NET_VERSION);
 	if (gate != NULL) {
-		strscpy(gate_buf, gate, sizeof(gate_buf));
+		strscpy(gate_buf, gate);
 		args = setup_args;
 	}
 	else args = nosetup_args;

arch/um/os-Linux/drivers/tuntap_user.c

@@ -146,7 +146,7 @@ static int tuntap_open(void *data)
 		}
 		memset(&ifr, 0, sizeof(ifr));
 		ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
-		strscpy(ifr.ifr_name, pri->dev_name, sizeof(ifr.ifr_name));
+		strscpy(ifr.ifr_name, pri->dev_name);
 		if (ioctl(pri->fd, TUNSETIFF, &ifr) < 0) {
 			err = -errno;
 			printk(UM_KERN_ERR "TUNSETIFF failed, errno = %d\n",

arch/um/os-Linux/umid.c

@@ -40,7 +40,7 @@ static int __init make_uml_dir(void)
 				__func__);
 			goto err;
 		}
-		strscpy(dir, home, sizeof(dir));
+		strscpy(dir, home);
 		uml_dir++;
 	}
 	strlcat(dir, uml_dir, sizeof(dir));
@@ -243,7 +243,7 @@ int __init set_umid(char *name)
 	if (strlen(name) > UMID_LEN - 1)
 		return -E2BIG;
 
-	strscpy(umid, name, sizeof(umid));
+	strscpy(umid, name);
 
 	return 0;
 }
@@ -262,7 +262,7 @@ static int __init make_umid(void)
 	make_uml_dir();
 
 	if (*umid == '\0') {
-		strscpy(tmp, uml_dir, sizeof(tmp));
+		strscpy(tmp, uml_dir);
 		strlcat(tmp, "XXXXXX", sizeof(tmp));
 		fd = mkstemp(tmp);
 		if (fd < 0) {