Start to add truncate checks on all uses of strlcpy(). Reading lwn

has it's uses :-).

Autobuild-User: Jeremy Allison <jra@samba.org>
Autobuild-Date: Thu Mar 29 20:48:15 CEST 2012 on sn-devel-104

4 files changed, 38 insertions, 25 deletions

diff --git a/lib/socket/interfaces.c b/lib/socket/interfaces.c
index 775956ba99..74c642372a 100644
--- a/lib/socket/interfaces.c
+++ b/lib/socket/interfaces.c
@@ -212,8 +212,12 @@ static int _get_interfaces(TALLOC_CTX *mem_ctx, struct iface_struct **pifaces)
 			continue;
 		}
 
-		strlcpy(ifaces[total].name, ifptr->ifa_name,
-			sizeof(ifaces[total].name));
+		if (strlcpy(ifaces[total].name, ifptr->ifa_name,
+			sizeof(ifaces[total].name)) >=
+				sizeof(ifaces[total].name)) {
+			/* Truncation ! Ignore. */
+			continue;
+		}
 		total++;
 	}
 
diff --git a/lib/util/fault.c b/lib/util/fault.c
index d0b34e540b..4f8e8db5ca 100644
--- a/lib/util/fault.c
+++ b/lib/util/fault.c
@@ -116,8 +116,6 @@ _PUBLIC_ const char *panic_action = NULL;
 */
 static void smb_panic_default(const char *why)
 {
-	int result;
-
 #if defined(HAVE_PRCTL) && defined(PR_SET_PTRACER)
 	/*
 	 * Make sure all children can attach a debugger.
@@ -126,20 +124,22 @@ static void smb_panic_default(const char *why)
 #endif
 
 	if (panic_action && *panic_action) {
-		char pidstr[20];
 		char cmdstring[200];
-		strlcpy(cmdstring, panic_action, sizeof(cmdstring));
-		snprintf(pidstr, sizeof(pidstr), "%d", (int) getpid());
-		all_string_sub(cmdstring, "%d", pidstr, sizeof(cmdstring));
-		DEBUG(0, ("smb_panic(): calling panic action [%s]\n", cmdstring));
-		result = system(cmdstring);
-
-		if (result == -1)
-			DEBUG(0, ("smb_panic(): fork failed in panic action: %s\n",
-				  strerror(errno)));
-		else
-			DEBUG(0, ("smb_panic(): action returned status %d\n",
-				  WEXITSTATUS(result)));
+		if (strlcpy(cmdstring, panic_action, sizeof(cmdstring)) < sizeof(cmdstring)) {
+			int result;
+			char pidstr[20];
+			snprintf(pidstr, sizeof(pidstr), "%d", (int) getpid());
+			all_string_sub(cmdstring, "%d", pidstr, sizeof(cmdstring));
+			DEBUG(0, ("smb_panic(): calling panic action [%s]\n", cmdstring));
+			result = system(cmdstring);
+
+			if (result == -1)
+				DEBUG(0, ("smb_panic(): fork failed in panic action: %s\n",
+					  strerror(errno)));
+			else
+				DEBUG(0, ("smb_panic(): action returned status %d\n",
+					  WEXITSTATUS(result)));
+		}
 	}
 	DEBUG(0,("PANIC: %s\n", why));
 
diff --git a/lib/util/util_net.c b/lib/util/util_net.c
index 637c52b988..69e5324180 100644
--- a/lib/util/util_net.c
+++ b/lib/util/util_net.c
@@ -107,9 +107,11 @@ static bool interpret_string_addr_pref(struct sockaddr_storage *pss,
 		 */
 
 		if (p && (p > str) && ((scope_id = if_nametoindex(p+1)) != 0)) {
-			strlcpy(addr, str,
-				MIN(PTR_DIFF(p,str)+1,
-					sizeof(addr)));
+			size_t len = MIN(PTR_DIFF(p,str)+1, sizeof(addr));
+			if (strlcpy(addr, str, len) >= len) {
+				/* Truncate. */
+				return false;
+			}
 			str = addr;
 		}
 	}
@@ -332,9 +334,11 @@ bool is_ipaddress_v6(const char *str)
 		 */
 
 		if (p && (p > str) && (if_nametoindex(p+1) != 0)) {
-			strlcpy(addr, str,
-				MIN(PTR_DIFF(p,str)+1,
-					sizeof(addr)));
+			size_t len = MIN(PTR_DIFF(p,str)+1, sizeof(addr));
+			if (strlcpy(addr, str, len) >= len) {
+				/* Truncate. */
+				return false;
+			}
 			sp = addr;
 		}
 		ret = inet_pton(AF_INET6, sp, &dest6);
@@ -723,7 +727,10 @@ static const char *get_socket_addr(int fd, char *addr_buf, size_t addr_len)
 	 * zero IPv6 address. No good choice here.
 	 */
 
-	strlcpy(addr_buf, "0.0.0.0", addr_len);
+	if (strlcpy(addr_buf, "0.0.0.0", addr_len) >= addr_len) {
+		/* Truncate ! */
+		return NULL;
+	}
 
 	if (fd == -1) {
 		return addr_buf;
diff --git a/source3/smbd/process.c b/source3/smbd/process.c
index ed19e7f42b..30dbc0c6dd 100644
--- a/source3/smbd/process.c
+++ b/source3/smbd/process.c
@@ -3037,7 +3037,9 @@ static NTSTATUS smbd_register_ips(struct smbd_server_connection *sconn,
 		return NT_STATUS_NO_MEMORY;
 	}
 
-	client_socket_addr(sconn->sock, tmp_addr, sizeof(tmp_addr));
+	if (client_socket_addr(sconn->sock, tmp_addr, sizeof(tmp_addr)) == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
 	addr = talloc_strdup(cconn, tmp_addr);
 	if (addr == NULL) {
 		return NT_STATUS_NO_MEMORY;