Merge pull request #570 from Snapchat/fix_snprint_uses

Fix snprintf uses to avoid hardcoded sizes

src/anet.c

@@ -441,7 +441,7 @@ static int _anetTcpServer(char *err, int port, const char *bindaddr, int af, int
     char _port[6];  /* strlen("65535") */
     struct addrinfo hints, *servinfo, *p;
 
-    snprintf(_port,6,"%d",port);
+    snprintf(_port,sizeof(_port),"%d",port);
     memset(&hints,0,sizeof(hints));
     hints.ai_family = af;
     hints.ai_socktype = SOCK_STREAM;

src/aof.cpp

@@ -1658,7 +1658,7 @@ int rewriteAppendOnlyFile(char *filename) {
 { // BEGIN GOTO SCOPED VARIABLES
     /* Note that we have to use a different temp name here compared to the
      * one used by rewriteAppendOnlyFileBackground() function. */
-    snprintf(tmpfile,256,"temp-rewriteaof-%d.aof", (int) getpid());
+    snprintf(tmpfile,sizeof(tmpfile),"temp-rewriteaof-%d.aof", (int) getpid());
     fp = fopen(tmpfile,"w");
     if (!fp) {
         serverLog(LL_WARNING, "Opening the temp file for AOF rewrite in rewriteAppendOnlyFile(): %s", strerror(errno));
@@ -1895,7 +1895,7 @@ int rewriteAppendOnlyFileBackground(void) {
         /* Child */
         redisSetProcTitle("keydb-aof-rewrite");
         redisSetCpuAffinity(g_pserver->aof_rewrite_cpulist);
-        snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) getpid());
+        snprintf(tmpfile,sizeof(tmpfile),"temp-rewriteaof-bg-%d.aof", (int) getpid());
         if (rewriteAppendOnlyFile(tmpfile) == C_OK) {
             sendChildCowInfo(CHILD_INFO_TYPE_AOF_COW_SIZE, "AOF rewrite");
             exitFromChild(0);
@@ -1944,10 +1944,10 @@ void bgrewriteaofCommand(client *c) {
 void aofRemoveTempFile(pid_t childpid) {
     char tmpfile[256];
 
-    snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) childpid);
+    snprintf(tmpfile,sizeof(tmpfile),"temp-rewriteaof-bg-%d.aof", (int) childpid);
     bg_unlink(tmpfile);
 
-    snprintf(tmpfile,256,"temp-rewriteaof-%d.aof", (int) childpid);
+    snprintf(tmpfile,sizeof(tmpfile),"temp-rewriteaof-%d.aof", (int) childpid);
     bg_unlink(tmpfile);
 }
 
@@ -1985,7 +1985,7 @@ void backgroundRewriteDoneHandler(int exitcode, int bysignal) {
         /* Flush the differences accumulated by the parent to the
          * rewritten AOF. */
         latencyStartMonitor(latency);
-        snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof",
+        snprintf(tmpfile,sizeof(tmpfile),"temp-rewriteaof-bg-%d.aof",
             (int)g_pserver->child_pid);
         newfd = open(tmpfile,O_WRONLY|O_APPEND);
         if (newfd == -1) {

src/cluster.cpp

@@ -5107,7 +5107,7 @@ void createDumpPayload(rio *payload, robj_roptr o, robj *key) {
     serverAssert(rdbSaveObject(payload,o,key));
     char szT[32];
     uint64_t mvcc = mvccFromObj(o);
-    snprintf(szT, 32, "%" PRIu64, mvcc);
+    snprintf(szT, sizeof(szT), "%" PRIu64, mvcc);
     serverAssert(rdbSaveAuxFieldStrStr(payload,"mvcc-tstamp", szT) != -1);
 
     /* Write the footer, this is how it looks like:

src/config.cpp

@@ -2588,7 +2588,7 @@ static int updateMaxclients(long long val, long long prev, const char **err) {
         adjustOpenFilesLimit();
         if (g_pserver->maxclients != val) {
             static char msg[128];
-            snprintf(msg, 128, "The operating system is not able to handle the specified number of clients, try with %d", g_pserver->maxclients);
+            snprintf(msg, sizeof(msg), "The operating system is not able to handle the specified number of clients, try with %d", g_pserver->maxclients);
             *err = msg;
             if (g_pserver->maxclients > prev) {
                 g_pserver->maxclients = prev;
@@ -2627,7 +2627,7 @@ static int updateMaxclients(long long val, long long prev, const char **err) {
 
                 if (res != AE_OK){
                     static char msg[128];
-                    snprintf(msg, 128,"Failed to post the request to change setsize for Thread %d", iel);
+                    snprintf(msg, sizeof(msg),"Failed to post the request to change setsize for Thread %d", iel);
                     *err = msg;
                     return 0;
                 }

src/dict.cpp

@@ -1577,7 +1577,7 @@ char *stringFromLongLong(long long value) {
     int len;
     char *s;
 
-    len = snprintf(buf,32,"%lld",value);
+    len = snprintf(buf,sizeof(buf),"%lld",value);
     s = zmalloc(len+1);
     memcpy(s, buf, len);
     s[len] = '\0';

src/endianconv.c

@@ -112,15 +112,15 @@ int endianconvTest(int argc, char *argv[], int accurate) {
     UNUSED(argv);
     UNUSED(accurate);
 
-    snprintf(buf,32,"ciaoroma");
+    snprintf(buf,sizeof(buf),"ciaoroma");
     memrev16(buf);
     printf("%s\n", buf);
 
-    snprintf(buf,32,"ciaoroma");
+    snprintf(buf,sizeof(buf),"ciaoroma");
     memrev32(buf);
     printf("%s\n", buf);
 
-    snprintf(buf,32,"ciaoroma");
+    snprintf(buf,sizeof(buf),"ciaoroma");
     memrev64(buf);
     printf("%s\n", buf);
 

src/keydb-diagnostic-tool.cpp

@@ -904,7 +904,7 @@ int main(int argc, const char **argv) {
 
     while (self_threads < config.max_threads) {
         for (int i = 0; i < config.numclients; i++) {
-            snprintf(command, 63, "SET %d %s\r\n", self_threads * config.numclients + i, set_value);
+            snprintf(command, sizeof(command), "SET %d %s\r\n", self_threads * config.numclients + i, set_value);
             createClient(command, strlen(command), NULL,self_threads);
         }
 

src/modules/hellotimer.c

@@ -51,8 +51,9 @@ int TimerCommand_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int
 
     for (int j = 0; j < 10; j++) {
         int delay = rand() % 5000;
-        char *buf = RedisModule_Alloc(256);
+        int bufsize = 256;
-        snprintf(buf,256,"After %d", delay);
+        char *buf = RedisModule_Alloc(bufsize);
+        snprintf(buf,bufsize,"After %d", delay);
         RedisModuleTimerID tid = RedisModule_CreateTimer(ctx,delay,timerHandler,buf);
         REDISMODULE_NOT_USED(tid);
     }

src/networking.cpp

@@ -145,7 +145,7 @@ client *createClient(connection *conn, int iel) {
     client_id = g_pserver->next_client_id.fetch_add(1);
     c->iel = iel;
     c->id = client_id;
-    snprintf(c->lock.szName, 56, "client %" PRIu64, client_id);
+    snprintf(c->lock.szName, sizeof(c->lock.szName), "client %" PRIu64, client_id);
     c->resp = 2;
     c->conn = conn;
     c->name = NULL;
@@ -777,11 +777,11 @@ void setDeferredAggregateLen(client *c, void *node, long length, char prefix) {
          * we return NULL in addReplyDeferredLen() */
         if (node == NULL) return;
         char lenstr[128];
-        size_t lenstr_len = snprintf(lenstr, 128, "%c%ld\r\n", prefix, length);
+        size_t lenstr_len = snprintf(lenstr, sizeof(lenstr), "%c%ld\r\n", prefix, length);
         setDeferredReply(c, node, lenstr, lenstr_len);
     } else {
         char lenstr[128];
-        int lenstr_len = snprintf(lenstr, 128, "%c%ld\r\n", prefix, length);
+        int lenstr_len = snprintf(lenstr, sizeof(lenstr), "%c%ld\r\n", prefix, length);
 
         size_t idxSplice = (size_t)node;
         serverAssert(idxSplice <= c->replyAsync->used);

src/rdb.cpp

@@ -1163,7 +1163,7 @@ int rdbSaveKeyValuePair(rio *rdb, robj_roptr key, robj_roptr val, const expireEn
 
     char szT[32];
     if (g_pserver->fActiveReplica) {
-        snprintf(szT, 32, "%" PRIu64, mvccFromObj(val));
+        snprintf(szT, sizeof(szT), "%" PRIu64, mvccFromObj(val));
         if (rdbSaveAuxFieldStrStr(rdb,"mvcc-tstamp", szT) == -1) return -1;
     }
 
@@ -1190,7 +1190,7 @@ int rdbSaveKeyValuePair(rio *rdb, robj_roptr key, robj_roptr val, const expireEn
         {
             if (itr.subkey() == nullptr)
                 continue;   // already saved
-            snprintf(szT, 32, "%lld", itr.when());
+            snprintf(szT, sizeof(szT), "%lld", itr.when());
             rdbSaveAuxFieldStrStr(rdb,"keydb-subexpire-key",itr.subkey());
             rdbSaveAuxFieldStrStr(rdb,"keydb-subexpire-when",szT);
         }
@@ -1490,7 +1490,7 @@ int rdbSaveFile(char *filename, const redisDbPersistentDataSnapshot **rgpdb, rdb
     rio rdb;
     int error = 0;
 
-    snprintf(tmpfile,256,"temp-%d-%d.rdb", getpid(), g_pserver->rdbThreadVars.tmpfileNum);
+    snprintf(tmpfile,sizeof(tmpfile),"temp-%d-%d.rdb", getpid(), g_pserver->rdbThreadVars.tmpfileNum);
     fp = fopen(tmpfile,"w");
     if (!fp) {
         char *cwdp = getcwd(cwd,MAXPATHLEN);

src/redis-cli.c

@@ -3293,8 +3293,8 @@ static redisReply *clusterManagerMigrateKeysInReply(clusterManagerNode *source,
     argv_len = zcalloc(argc * sizeof(size_t), MALLOC_LOCAL);
     char portstr[255];
     char timeoutstr[255];
-    snprintf(portstr, 10, "%d", target->port);
+    snprintf(portstr, sizeof(portstr), "%d", target->port);
-    snprintf(timeoutstr, 10, "%d", timeout);
+    snprintf(timeoutstr, sizeof(timeoutstr), "%d", timeout);
     argv[0] = "MIGRATE";
     argv_len[0] = 7;
     argv[1] = target->ip;
@@ -6825,7 +6825,7 @@ static long getLongInfoField(char *info, char *field) {
 
 /* Convert number of bytes into a human readable string of the form:
  * 100B, 2G, 100M, 4K, and so forth. */
-void bytesToHuman(char *s, long long n) {
+void bytesToHuman(char *s, long long n, size_t bufsize) {
     double d;
 
     if (n < 0) {
@@ -6835,17 +6835,17 @@ void bytesToHuman(char *s, long long n) {
     }
     if (n < 1024) {
         /* Bytes */
-        snprintf(s,256,"%lldB",n);
+        snprintf(s,bufsize,"%lldB",n);
         return;
     } else if (n < (1024*1024)) {
         d = (double)n/(1024);
-        snprintf(s,256,"%.2fK",d);
+        snprintf(s,bufsize,"%.2fK",d);
     } else if (n < (1024LL*1024*1024)) {
         d = (double)n/(1024*1024);
-        snprintf(s,256,"%.2fM",d);
+        snprintf(s,bufsize,"%.2fM",d);
     } else if (n < (1024LL*1024*1024*1024)) {
         d = (double)n/(1024LL*1024*1024);
-        snprintf(s,256,"%.2fG",d);
+        snprintf(s,bufsize,"%.2fG",d);
     }
 }
 
@@ -6875,38 +6875,38 @@ static void statMode(void) {
         for (j = 0; j < 20; j++) {
             long k;
 
-            snprintf(buf,64,"db%d:keys",j);
+            snprintf(buf,sizeof(buf),"db%d:keys",j);
             k = getLongInfoField(reply->str,buf);
             if (k == LONG_MIN) continue;
             aux += k;
         }
-        snprintf(buf,64,"%ld",aux);
+        snprintf(buf,sizeof(buf),"%ld",aux);
         printf("%-11s",buf);
 
         /* Used memory */
         aux = getLongInfoField(reply->str,"used_memory");
-        bytesToHuman(buf,aux);
+        bytesToHuman(buf,aux,sizeof(buf));
         printf("%-8s",buf);
 
         /* Clients */
         aux = getLongInfoField(reply->str,"connected_clients");
-        snprintf(buf,64,"%ld",aux);
+        snprintf(buf,sizeof(buf),"%ld",aux);
         printf(" %-8s",buf);
 
         /* Blocked (BLPOPPING) Clients */
         aux = getLongInfoField(reply->str,"blocked_clients");
-        snprintf(buf,64,"%ld",aux);
+        snprintf(buf,sizeof(buf),"%ld",aux);
         printf("%-8s",buf);
 
         /* Requests */
         aux = getLongInfoField(reply->str,"total_commands_processed");
-        snprintf(buf,64,"%ld (+%ld)",aux,requests == 0 ? 0 : aux-requests);
+        snprintf(buf,sizeof(buf),"%ld (+%ld)",aux,requests == 0 ? 0 : aux-requests);
         printf("%-19s",buf);
         requests = aux;
 
         /* Connections */
         aux = getLongInfoField(reply->str,"total_connections_received");
-        snprintf(buf,64,"%ld",aux);
+        snprintf(buf,sizeof(buf),"%ld",aux);
         printf(" %-12s",buf);
 
         /* Children */

src/replication.cpp

@@ -3736,7 +3736,7 @@ retry_connect:
         while(maxtries--) {
             auto dt = std::chrono::system_clock::now().time_since_epoch();
             auto dtMillisecond = std::chrono::duration_cast<std::chrono::milliseconds>(dt);
-            snprintf(tmpfile,256,
+            snprintf(tmpfile,sizeof(tmpfile),
                 "temp-%d.%ld.rdb",(int)dtMillisecond.count(),(long int)getpid());
             dfd = open(tmpfile,O_CREAT|O_WRONLY|O_EXCL,0644);
             if (dfd != -1) break;

src/server.cpp

@@ -5471,30 +5471,30 @@ NULL
 
 /* Convert an amount of bytes into a human readable string in the form
  * of 100B, 2G, 100M, 4K, and so forth. */
-void bytesToHuman(char *s, unsigned long long n) {
+void bytesToHuman(char *s, unsigned long long n, size_t bufsize) {
     double d;
 
     if (n < 1024) {
         /* Bytes */
-        snprintf(s,256,"%lluB",n);
+        snprintf(s,bufsize,"%lluB",n);
     } else if (n < (1024*1024)) {
         d = (double)n/(1024);
-        snprintf(s,256,"%.2fK",d);
+        snprintf(s,bufsize,"%.2fK",d);
     } else if (n < (1024LL*1024*1024)) {
         d = (double)n/(1024*1024);
-        snprintf(s,256,"%.2fM",d);
+        snprintf(s,bufsize,"%.2fM",d);
     } else if (n < (1024LL*1024*1024*1024)) {
         d = (double)n/(1024LL*1024*1024);
-        snprintf(s,256,"%.2fG",d);
+        snprintf(s,bufsize,"%.2fG",d);
     } else if (n < (1024LL*1024*1024*1024*1024)) {
         d = (double)n/(1024LL*1024*1024*1024);
-        snprintf(s,256,"%.2fT",d);
+        snprintf(s,bufsize,"%.2fT",d);
     } else if (n < (1024LL*1024*1024*1024*1024*1024)) {
         d = (double)n/(1024LL*1024*1024*1024*1024);
-        snprintf(s,256,"%.2fP",d);
+        snprintf(s,bufsize,"%.2fP",d);
     } else {
         /* Let's hope we never need this */
-        snprintf(s,256,"%lluB",n);
+        snprintf(s,bufsize,"%lluB",n);
     }
 }
 
@@ -5670,13 +5670,13 @@ sds genRedisInfoString(const char *section) {
         if (zmalloc_used > g_pserver->stat_peak_memory)
             g_pserver->stat_peak_memory = zmalloc_used;
 
-        bytesToHuman(hmem,zmalloc_used);
+        bytesToHuman(hmem,zmalloc_used,sizeof(hmem));
-        bytesToHuman(peak_hmem,g_pserver->stat_peak_memory);
+        bytesToHuman(peak_hmem,g_pserver->stat_peak_memory,sizeof(peak_hmem));
-        bytesToHuman(total_system_hmem,total_system_mem);
+        bytesToHuman(total_system_hmem,total_system_mem,sizeof(total_system_hmem));
-        bytesToHuman(used_memory_lua_hmem,memory_lua);
+        bytesToHuman(used_memory_lua_hmem,memory_lua,sizeof(used_memory_lua_hmem));
-        bytesToHuman(used_memory_scripts_hmem,mh->lua_caches);
+        bytesToHuman(used_memory_scripts_hmem,mh->lua_caches,sizeof(used_memory_scripts_hmem));
-        bytesToHuman(used_memory_rss_hmem,g_pserver->cron_malloc_stats.process_rss);
+        bytesToHuman(used_memory_rss_hmem,g_pserver->cron_malloc_stats.process_rss,sizeof(used_memory_rss_hmem));
-        bytesToHuman(maxmemory_hmem,g_pserver->maxmemory);
+        bytesToHuman(maxmemory_hmem,g_pserver->maxmemory,sizeof(maxmemory_hmem));
 
         if (sections++) info = sdscat(info,"\r\n");
         info = sdscatprintf(info,
@@ -6563,7 +6563,8 @@ void usage(void) {
 
 void redisAsciiArt(void) {
 #include "asciilogo.h"
-    char *buf = (char*)zmalloc(1024*16, MALLOC_LOCAL);
+    size_t bufsize = 1024*16;
+    char *buf = (char*)zmalloc(bufsize, MALLOC_LOCAL);
     const char *mode;
 
     if (g_pserver->cluster_enabled) mode = "cluster";
@@ -6585,7 +6586,7 @@ void redisAsciiArt(void) {
         );
     } else {
         sds motd = fetchMOTD(true, cserver.enable_motd);
-        snprintf(buf,1024*16,ascii_logo,
+        snprintf(buf,bufsize,ascii_logo,
             KEYDB_REAL_VERSION,
             redisGitSHA1(),
             strtol(redisGitDirty(),NULL,10) > 0,

src/tls.cpp

@@ -616,8 +616,9 @@ bool tlsValidateCertificateName(tls_connection* conn){
     /* If neither the CN nor the SANs match, update the SSL error and return false */
     conn->c.last_errno = 0;
     if (conn->ssl_error) zfree(conn->ssl_error);
-    conn->ssl_error = (char*)zmalloc(512);
+    size_t bufsize = 512;
-    snprintf(conn->ssl_error, 512, "Client CN (%s) and SANs not found in allowlist.", commonName);
+    conn->ssl_error = (char*)zmalloc(bufsize);
+    snprintf(conn->ssl_error, bufsize, "Client CN (%s) and SANs not found in allowlist.", commonName);
     return false;
 }
 

src/ziplist.c

@@ -1704,17 +1704,17 @@ static unsigned char *createIntList() {
     unsigned char *zl = ziplistNew();
     char buf[32];
 
-    snprintf(buf, 32, "100");
+    snprintf(buf, sizeof(buf), "100");
     zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_TAIL);
-    snprintf(buf, 32, "128000");
+    snprintf(buf, sizeof(buf), "128000");
     zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_TAIL);
-    snprintf(buf, 32, "-100");
+    snprintf(buf, sizeof(buf), "-100");
     zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_HEAD);
-    snprintf(buf, 32, "4294967296");
+    snprintf(buf, sizeof(buf), "4294967296");
     zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_HEAD);
-    snprintf(buf, 32, "non integer");
+    snprintf(buf, sizeof(buf), "non integer");
     zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_TAIL);
-    snprintf(buf, 32, "much much longer non integer");
+    snprintf(buf, sizeof(buf), "much much longer non integer");
     zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_TAIL);
     return zl;
 }
@@ -2228,7 +2228,7 @@ int ziplistTest(int argc, char **argv, int accurate) {
         char buf[32];
         int i,len;
         for (i = 0; i < 1000; i++) {
-            len = snprintf(buf,32,"%d",i);
+            len = snprintf(buf,sizeof(buf),"%d",i);
             zl = ziplistPush(zl,(unsigned char*)buf,len,ZIPLIST_TAIL);
         }
         for (i = 0; i < 1000; i++) {
@@ -2375,13 +2375,13 @@ int ziplistTest(int argc, char **argv, int accurate) {
                 } else {
                     switch(rand() % 3) {
                     case 0:
-                        buflen = snprintf(buf,1024,"%lld",(0LL + rand()) >> 20);
+                        buflen = snprintf(buf,sizeof(buf),"%lld",(0LL + rand()) >> 20);
                         break;
                     case 1:
-                        buflen = snprintf(buf,1024,"%lld",(0LL + rand()));
+                        buflen = snprintf(buf,sizeof(buf),"%lld",(0LL + rand()));
                         break;
                     case 2:
-                        buflen = snprintf(buf,1024,"%lld",(0LL + rand()) << 20);
+                        buflen = snprintf(buf,sizeof(buf),"%lld",(0LL + rand()) << 20);
                         break;
                     default:
                         assert(NULL);
@@ -2410,7 +2410,7 @@ int ziplistTest(int argc, char **argv, int accurate) {
 
                 assert(ziplistGet(p,&sstr,&slen,&sval));
                 if (sstr == NULL) {
-                    buflen = snprintf(buf,1024,"%lld",sval);
+                    buflen = snprintf(buf,sizeof(buf),"%lld",sval);
                 } else {
                     buflen = slen;
                     memcpy(buf,sstr,buflen);

src/zmalloc.cpp

@@ -370,7 +370,7 @@ size_t zmalloc_get_rss(void) {
     int fd, count;
     char *p, *x;
 
-    snprintf(filename,256,"/proc/%ld/stat",(long) getpid());
+    snprintf(filename,sizeof(filename),"/proc/%ld/stat",(long) getpid());
     if ((fd = open(filename,O_RDONLY)) == -1) return 0;
     if (read(fd,buf,4096) <= 0) {
         close(fd);
@@ -462,7 +462,7 @@ size_t zmalloc_get_rss(void) {
     char filename[256];
     int fd;
 
-    snprintf(filename,256,"/proc/%ld/psinfo",(long) getpid());
+    snprintf(filename,sizeof(filename),"/proc/%ld/psinfo",(long) getpid());
 
     if ((fd = open(filename,O_RDONLY)) == -1) return 0;
     if (ioctl(fd, PIOCPSINFO, &info) == -1) {
@@ -521,7 +521,7 @@ int jemalloc_purge() {
     unsigned narenas = 0;
     size_t sz = sizeof(unsigned);
     if (!je_mallctl("arenas.narenas", &narenas, &sz, NULL, 0)) {
-        snprintf(tmp, 32, "arena.%d.purge", narenas);
+        snprintf(tmp, sizeof(tmp), "arena.%d.purge", narenas);
         if (!je_mallctl(tmp, NULL, 0, NULL, 0))
             return 0;
     }