Merge pull request #223 from pi-hole/fix/memory_checks

Improve memory checks

FTL.h

@@ -254,3 +254,14 @@ bool rereadgravity;
 long int lastDBimportedtimestamp;
 bool ipv4telnet, ipv6telnet;
 bool istelnet[MAXCONNS];
+
+// Use out own memory handling functions that will detect possible errors
+// and report accordingly in the log. This will make debugging FTL crashs
+// caused by insufficient memory or by code bugs (not properly dealing
+// with NULL pointers) much easier.
+#define free(param) FTLfree(param, __FILE__,  __FUNCTION__,  __LINE__)
+#define lib_strdup() strdup()
+#undef strdup
+#define strdup(param) FTLstrdup(param, __FILE__,  __FUNCTION__,  __LINE__)
+#define calloc(p1,p2) FTLcalloc(p1,p2, __FILE__,  __FUNCTION__,  __LINE__)
+#define realloc(p1,p2) FTLrealloc(p1,p2, __FILE__,  __FUNCTION__,  __LINE__)

Makefile

@@ -9,7 +9,7 @@
 # Please see LICENSE file for your rights under this license.
 
 DEPS = FTL.h routines.h api.h version.h
-OBJ = main.o structs.o log.o daemon.o parser.o signals.o socket.o request.o grep.o setupVars.o args.o flush.o threads.o gc.o config.o database.o api.o msgpack.o
+OBJ = main.o memory.o log.o daemon.o parser.o signals.o socket.o request.o grep.o setupVars.o args.o flush.o threads.o gc.o config.o database.o api.o msgpack.o
 
 # Get git commit version and date
 GIT_BRANCH := $(shell git branch | sed -n 's/^\* //p')

api.c

@@ -272,6 +272,7 @@ void getTopDomains(char *client_message, int *sock)
 					ssend(*sock, "%i %i %s wildcard\n", n, domains[j].blockedcount, domains[j].domain);
 				else {
 					char *fancyWildcard = calloc(3 + strlen(domains[j].domain), sizeof(char));
+					if(fancyWildcard == NULL) return;
 					sprintf(fancyWildcard, "*.%s", domains[j].domain);
 
 					if(!pack_str32(*sock, fancyWildcard))
@@ -466,10 +467,8 @@ void getForwardDestinations(char *client_message, int *sock)
 		// Is this the "local" forward destination?
 		if(j == counters.forwarded)
 		{
-			ip = calloc(4,1);
-			strcpy(ip, "::1");
-			name = calloc(6,1);
-			strcpy(name, "local");
+			ip = strdup("::1");
+			name = strdup("local");
 
 			if(totalqueries > 0)
 				// Whats the percentage of (cached + blocked) queries on the total amount of queries?
@@ -582,15 +581,17 @@ void getAllQueries(char *client_message, int *sock)
 	if(command(client_message, ">getallqueries-domain")) {
 		// Get domain name we want to see only (limit length to 255 chars)
 		domainname = calloc(256, sizeof(char));
+		if(domainname == NULL) return;
 		sscanf(client_message, ">getallqueries-domain %255s", domainname);
 		if(debugclients)
 			logg("Showing only queries with domain %s", domainname);
 		filterdomainname = true;
 	}
 	// Client filtering?
 	if(command(client_message, ">getallqueries-client")) {
-		clientname = calloc(256, sizeof(char));
 		// Get client name we want to see only (limit length to 255 chars)
+		clientname = calloc(256, sizeof(char));
+		if(clientname == NULL) return;
 		sscanf(client_message, ">getallqueries-client %255s", clientname);
 		if(debugclients)
 			logg("Showing only queries with client %s", clientname);
@@ -785,6 +786,7 @@ void getMemoryUsage(int *sock)
 {
 	unsigned long int structbytes = sizeof(countersStruct) + sizeof(ConfigStruct) + counters.queries_MAX*sizeof(queriesDataStruct) + counters.forwarded_MAX*sizeof(forwardedDataStruct) + counters.clients_MAX*sizeof(clientsDataStruct) + counters.domains_MAX*sizeof(domainsDataStruct) + counters.overTime_MAX*sizeof(overTimeDataStruct) + (counters.wildcarddomains)*sizeof(*wildcarddomains);
 	char *structprefix = calloc(2, sizeof(char));
+	if(structprefix == NULL) return;
 	double formated = 0.0;
 	format_memory_size(structprefix, structbytes, &formated);
 
@@ -796,6 +798,7 @@ void getMemoryUsage(int *sock)
 
 	unsigned long int dynamicbytes = memory.wildcarddomains + memory.domainnames + memory.clientips + memory.clientnames + memory.forwardedips + memory.forwardednames + memory.forwarddata;
 	char *dynamicprefix = calloc(2, sizeof(char));
+	if(dynamicprefix == NULL) return;
 	format_memory_size(dynamicprefix, dynamicbytes, &formated);
 
 	if(istelnet[*sock])
@@ -806,6 +809,7 @@ void getMemoryUsage(int *sock)
 
 	unsigned long int totalbytes = structbytes + dynamicbytes;
 	char *totalprefix = calloc(2, sizeof(char));
+	if(totalprefix == NULL) return;
 	format_memory_size(totalprefix, totalbytes, &formated);
 
 	if(istelnet[*sock])
@@ -1020,6 +1024,7 @@ void getVersion(int *sock)
 			ssend(*sock, "version vDev-%s\ntag %s\nbranch %s\ndate %s\n", hash, tag, GIT_BRANCH, GIT_DATE);
 		else {
 			char *hashVersion = calloc(6 + strlen(hash), sizeof(char));
+			if(hashVersion == NULL) return;
 			sprintf(hashVersion, "vDev-%s", hash);
 
 			if(!pack_str32(*sock, hashVersion) ||
@@ -1048,6 +1053,7 @@ void getDBstats(int *sock)
 		filesize = st.st_size;
 
 	char *prefix = calloc(2, sizeof(char));
+	if(prefix == NULL) return;
 	double formated = 0.0;
 	format_memory_size(prefix, filesize, &formated);
 

daemon.c

@@ -252,13 +252,12 @@ char *getUserName(void)
 	struct passwd *pw = getpwuid(euid);
 	if(pw)
 	{
-		username = calloc(strlen(pw->pw_name)+1, sizeof(char));
-		strcpy(username, pw->pw_name);
+		username = strdup(pw->pw_name);
 	}
 	else
 	{
-		username = calloc(12, sizeof(char));
-		sprintf(username, "%i", euid);
+		if(asprintf(&username, "%i", euid) < 0)
+			return NULL;
 	}
 
 	return username;

grep.c

@@ -151,6 +151,7 @@ void readWildcardsList()
 				memory_check(WILDCARD);
 				// Allocate space for new domain entry and save domain
 				wildcarddomains[counters.wildcarddomains] = calloc(strlen(domain)+1,sizeof(char));
+				if(wildcarddomains[counters.wildcarddomains] == NULL) return;
 				memory.wildcarddomains += (strlen(domain) + 1) * sizeof(char);
 				strcpy(wildcarddomains[counters.wildcarddomains], domain);
 

log.c

@@ -120,6 +120,7 @@ void logg_struct_resize(const char* str, int to, int step)
 
 	unsigned long int bytes = structbytes + dynamicbytes;
 	char *prefix = calloc(2, sizeof(char));
+	if(prefix == NULL) return;
 	double formated = 0.0;
 	format_memory_size(prefix, bytes, &formated);