NFS: Add string length argument to nfs_parse_server_address

To make nfs_parse_server_address() more generally useful, allow it to accept input strings that are not terminated with '\0'. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Add string length argument to nfs_parse_server_address
To make nfs_parse_server_address() more generally useful, allow it to accept input strings that are not terminated with '\0'. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Chuck Lever · Trond Myklebust
1 parent d1aa082573
Showing 2 changed files with 77 additions and 30 deletions Side-by-side Diff
fs/nfs/super.c
include/linux/inet.h
@@ -705,41 +705,79 @@
 	return 0;
 }
  
-/*
- * Parse string addresses passed in via a mount option,
- * and construct a sockaddr based on the result.
- *
- * If address parsing fails, set the sockaddr's address
- * family to AF_UNSPEC to force nfs_verify_server_address()
- * to punt the mount.
- */
-static void nfs_parse_server_address(char *value,
-				     struct sockaddr *sap,
-				     size_t *len)
+static void nfs_parse_ipv4_address(char *string, size_t str_len,
+				   struct sockaddr *sap, size_t *addr_len)
 {
-	if (strchr(value, ':')) {
-		struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
-		u8 *addr = (u8 *)&ap->sin6_addr.in6_u;
+	struct sockaddr_in *sin = (struct sockaddr_in *)sap;
+	u8 *addr = (u8 *)&sin->sin_addr.s_addr;
  
-		ap->sin6_family = AF_INET6;
-		*len = sizeof(*ap);
-		if (in6_pton(value, -1, addr, '\0', NULL))
+	if (str_len <= INET_ADDRSTRLEN) {
+		dfprintk(MOUNT, "NFS: parsing IPv4 address %*s\n",
+				(int)str_len, string);
+
+		sin->sin_family = AF_INET;
+		*addr_len = sizeof(*sin);
+		if (in4_pton(string, str_len, addr, '\0', NULL))
 			return;
-	} else {
-		struct sockaddr_in *ap = (struct sockaddr_in *)sap;
-		u8 *addr = (u8 *)&ap->sin_addr.s_addr;
+	}
  
-		ap->sin_family = AF_INET;
-		*len = sizeof(*ap);
-		if (in4_pton(value, -1, addr, '\0', NULL))
+	sap->sa_family = AF_UNSPEC;
+	*addr_len = 0;
+}
+
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+static void nfs_parse_ipv6_address(char *string, size_t str_len,
+				   struct sockaddr *sap, size_t *addr_len)
+{
+	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
+	u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;
+
+	if (str_len <= INET6_ADDRSTRLEN) {
+		dfprintk(MOUNT, "NFS: parsing IPv6 address %*s\n",
+				(int)str_len, string);
+
+		sin6->sin6_family = AF_INET6;
+		*addr_len = sizeof(*sin6);
+		if (in6_pton(string, str_len, addr, '\0', NULL))
 			return;
 	}
  
 	sap->sa_family = AF_UNSPEC;
-	*len = 0;
+	*addr_len = 0;
 }
+#else
+static void nfs_parse_ipv6_address(char *string, size_t str_len,
+				   struct sockaddr *sap, size_t *addr_len)
+{
+	sap->sa_family = AF_UNSPEC;
+	*addr_len = 0;
+}
+#endif
  
 /*
+ * Construct a sockaddr based on the contents of a string that contains
+ * an IP address in presentation format.
+ *
+ * If there is a problem constructing the new sockaddr, set the address
+ * family to AF_UNSPEC.
+ */
+static void nfs_parse_ip_address(char *string, size_t str_len,
+				 struct sockaddr *sap, size_t *addr_len)
+{
+	unsigned int i, colons;
+
+	colons = 0;
+	for (i = 0; i < str_len; i++)
+		if (string[i] == ':')
+			colons++;
+
+	if (colons >= 2)
+		nfs_parse_ipv6_address(string, str_len, sap, addr_len);
+	else
+		nfs_parse_ipv4_address(string, str_len, sap, addr_len);
+}
+
+/*
  * Error-check and convert a string of mount options from user space into
  * a data structure
  */
@@ -1070,9 +1108,10 @@
 			string = match_strdup(args);
 			if (string == NULL)
 				goto out_nomem;
-			nfs_parse_server_address(string, (struct sockaddr *)
-						 &mnt->nfs_server.address,
-						 &mnt->nfs_server.addrlen);
+			nfs_parse_ip_address(string, strlen(string),
+					     (struct sockaddr *)
+						&mnt->nfs_server.address,
+					     &mnt->nfs_server.addrlen);
 			kfree(string);
 			break;
 		case Opt_clientaddr:
@@ -1093,9 +1132,10 @@
 			string = match_strdup(args);
 			if (string == NULL)
 				goto out_nomem;
-			nfs_parse_server_address(string, (struct sockaddr *)
-						 &mnt->mount_server.address,
-						 &mnt->mount_server.addrlen);
+			nfs_parse_ip_address(string, strlen(string),
+					     (struct sockaddr *)
+						&mnt->mount_server.address,
+					     &mnt->mount_server.addrlen);
 			kfree(string);
 			break;
  
@@ -44,6 +44,13 @@
  
 #include <linux/types.h>
  
+/*
+ * These mimic similar macros defined in user-space for inet_ntop(3).
+ * See /usr/include/netinet/in.h .
+ */
+#define INET_ADDRSTRLEN		(16)
+#define INET6_ADDRSTRLEN	(48)
+
 extern __be32 in_aton(const char *str);
 extern int in4_pton(const char *src, int srclen, u8 *dst, int delim, const char **end);
 extern int in6_pton(const char *src, int srclen, u8 *dst, int delim, const char **end);
...	...	@@ -705,41 +705,79 @@
705	705	return 0;
706	706	}
707	707
708		-/*
709		- * Parse string addresses passed in via a mount option,
710		- * and construct a sockaddr based on the result.
711		- *
712		- * If address parsing fails, set the sockaddr's address
713		- * family to AF_UNSPEC to force nfs_verify_server_address()
714		- * to punt the mount.
715		- */
716		-static void nfs_parse_server_address(char *value,
717		- struct sockaddr *sap,
718		- size_t *len)
	708	+static void nfs_parse_ipv4_address(char *string, size_t str_len,
	709	+ struct sockaddr sap, size_t addr_len)
719	710	{
720		- if (strchr(value, ':')) {
721		- struct sockaddr_in6 ap = (struct sockaddr_in6 )sap;
722		- u8 addr = (u8 )&ap->sin6_addr.in6_u;
	711	+ struct sockaddr_in sin = (struct sockaddr_in )sap;
	712	+ u8 addr = (u8 )&sin->sin_addr.s_addr;
723	713
724		- ap->sin6_family = AF_INET6;
725		- len = sizeof(ap);
726		- if (in6_pton(value, -1, addr, '\0', NULL))
	714	+ if (str_len <= INET_ADDRSTRLEN) {
	715	+ dfprintk(MOUNT, "NFS: parsing IPv4 address %*s\n",
	716	+ (int)str_len, string);
	717	+
	718	+ sin->sin_family = AF_INET;
	719	+ addr_len = sizeof(sin);
	720	+ if (in4_pton(string, str_len, addr, '\0', NULL))
727	721	return;
728		- } else {
729		- struct sockaddr_in ap = (struct sockaddr_in )sap;
730		- u8 addr = (u8 )&ap->sin_addr.s_addr;
	722	+ }
731	723
732		- ap->sin_family = AF_INET;
733		- len = sizeof(ap);
734		- if (in4_pton(value, -1, addr, '\0', NULL))
	724	+ sap->sa_family = AF_UNSPEC;
	725	+ *addr_len = 0;
	726	+}
	727	+
	728	+#if defined(CONFIG_IPV6) \|\| defined(CONFIG_IPV6_MODULE)
	729	+static void nfs_parse_ipv6_address(char *string, size_t str_len,
	730	+ struct sockaddr sap, size_t addr_len)
	731	+{
	732	+ struct sockaddr_in6 sin6 = (struct sockaddr_in6 )sap;
	733	+ u8 addr = (u8 )&sin6->sin6_addr.in6_u;
	734	+
	735	+ if (str_len <= INET6_ADDRSTRLEN) {
	736	+ dfprintk(MOUNT, "NFS: parsing IPv6 address %*s\n",
	737	+ (int)str_len, string);
	738	+
	739	+ sin6->sin6_family = AF_INET6;
	740	+ addr_len = sizeof(sin6);
	741	+ if (in6_pton(string, str_len, addr, '\0', NULL))
735	742	return;
736	743	}
737	744
738	745	sap->sa_family = AF_UNSPEC;
739		- *len = 0;
	746	+ *addr_len = 0;
740	747	}
	748	+#else
	749	+static void nfs_parse_ipv6_address(char *string, size_t str_len,
	750	+ struct sockaddr sap, size_t addr_len)
	751	+{
	752	+ sap->sa_family = AF_UNSPEC;
	753	+ *addr_len = 0;
	754	+}
	755	+#endif
741	756
742	757	/*
	758	+ * Construct a sockaddr based on the contents of a string that contains
	759	+ * an IP address in presentation format.
	760	+ *
	761	+ * If there is a problem constructing the new sockaddr, set the address
	762	+ * family to AF_UNSPEC.
	763	+ */
	764	+static void nfs_parse_ip_address(char *string, size_t str_len,
	765	+ struct sockaddr sap, size_t addr_len)
	766	+{
	767	+ unsigned int i, colons;
	768	+
	769	+ colons = 0;
	770	+ for (i = 0; i < str_len; i++)
	771	+ if (string[i] == ':')
	772	+ colons++;
	773	+
	774	+ if (colons >= 2)
	775	+ nfs_parse_ipv6_address(string, str_len, sap, addr_len);
	776	+ else
	777	+ nfs_parse_ipv4_address(string, str_len, sap, addr_len);
	778	+}
	779	+
	780	+/*
743	781	* Error-check and convert a string of mount options from user space into
744	782	* a data structure
745	783	*/
...	...	@@ -1070,9 +1108,10 @@
1070	1108	string = match_strdup(args);
1071	1109	if (string == NULL)
1072	1110	goto out_nomem;
1073		- nfs_parse_server_address(string, (struct sockaddr *)
1074		- &mnt->nfs_server.address,
1075		- &mnt->nfs_server.addrlen);
	1111	+ nfs_parse_ip_address(string, strlen(string),
	1112	+ (struct sockaddr *)
	1113	+ &mnt->nfs_server.address,
	1114	+ &mnt->nfs_server.addrlen);
1076	1115	kfree(string);
1077	1116	break;
1078	1117	case Opt_clientaddr:
...	...	@@ -1093,9 +1132,10 @@
1093	1132	string = match_strdup(args);
1094	1133	if (string == NULL)
1095	1134	goto out_nomem;
1096		- nfs_parse_server_address(string, (struct sockaddr *)
1097		- &mnt->mount_server.address,
1098		- &mnt->mount_server.addrlen);
	1135	+ nfs_parse_ip_address(string, strlen(string),
	1136	+ (struct sockaddr *)
	1137	+ &mnt->mount_server.address,
	1138	+ &mnt->mount_server.addrlen);
1099	1139	kfree(string);
1100	1140	break;
1101	1141
...	...	@@ -44,6 +44,13 @@
44	44
45	45	#include <linux/types.h>
46	46
	47	+/*
	48	+ * These mimic similar macros defined in user-space for inet_ntop(3).
	49	+ * See /usr/include/netinet/in.h .
	50	+ */
	51	+#define INET_ADDRSTRLEN (16)
	52	+#define INET6_ADDRSTRLEN (48)
	53	+
47	54	extern __be32 in_aton(const char *str);
48	55	extern int in4_pton(const char src, int srclen, u8 dst, int delim, const char **end);
49	56	extern int in6_pton(const char src, int srclen, u8 dst, int delim, const char **end);