Fixed bug in AOF rewrite not working because of integer overflow

[redis.git] / src / cluster.c

diff --git a/src/cluster.c b/src/cluster.c
index 9588920121ec55f2072dd1ed0b9a6f0bc6bbf5d5..3e65af7899e05f071585437ed5ac42ba5995193b 100644 (file)
--- a/src/cluster.c
+++ b/src/cluster.c
@@ -1014,11 +1014,24 @@ int clusterNodeGetSlotBit(clusterNode *n, int slot) {
  * If the slot is already assigned to another instance this is considered
  * an error and REDIS_ERR is returned. */
 int clusterAddSlot(clusterNode *n, int slot) {
  * If the slot is already assigned to another instance this is considered
  * an error and REDIS_ERR is returned. */
 int clusterAddSlot(clusterNode *n, int slot) {

-    redisAssert(clusterNodeSetSlotBit(n,slot) == 0);
+    if (clusterNodeSetSlotBit(n,slot) != 0)
+        return REDIS_ERR;

     server.cluster.slots[slot] = n;
     return REDIS_OK;
 }
 
     server.cluster.slots[slot] = n;
     return REDIS_OK;
 }
 

+/* Delete the specified slot marking it as unassigned.
+ * Returns REDIS_OK if the slot was assigned, otherwise if the slot was
+ * already unassigned REDIS_ERR is returned. */
+int clusterDelSlot(int slot) {
+    clusterNode *n = server.cluster.slots[slot];
+
+    if (!n) return REDIS_ERR;
+    redisAssert(clusterNodeClearSlotBit(n,slot) == 1);
+    server.cluster.slots[slot] = NULL;
+    return REDIS_OK;
+}
+

 /* -----------------------------------------------------------------------------
  * Cluster state evaluation function
  * -------------------------------------------------------------------------- */
 /* -----------------------------------------------------------------------------
  * Cluster state evaluation function
  * -------------------------------------------------------------------------- */


@@ -1128,6 +1141,18 @@ sds clusterGenNodesDescription(void) {
     return ci;
 }
 
     return ci;
 }
 

+int getSlotOrReply(redisClient *c, robj *o) {
+    long long slot;
+
+    if (getLongLongFromObject(o,&slot) != REDIS_OK ||
+        slot < 0 || slot > REDIS_CLUSTER_SLOTS)
+    {
+        addReplyError(c,"Invalid or out of range slot");
+        return -1;
+    }
+    return (int) slot;
+}
+

 void clusterCommand(redisClient *c) {
     if (server.cluster_enabled == 0) {
         addReplyError(c,"This instance has cluster support disabled");
 void clusterCommand(redisClient *c) {
     if (server.cluster_enabled == 0) {
         addReplyError(c,"This instance has cluster support disabled");


@@ -1165,24 +1190,26 @@ void clusterCommand(redisClient *c) {
         o = createObject(REDIS_STRING,ci);
         addReplyBulk(c,o);
         decrRefCount(o);
         o = createObject(REDIS_STRING,ci);
         addReplyBulk(c,o);
         decrRefCount(o);

-    } else if (!strcasecmp(c->argv[1]->ptr,"addslots") && c->argc >= 3) {
-        int j;
-        long long slot;
+    } else if ((!strcasecmp(c->argv[1]->ptr,"addslots") ||
+               !strcasecmp(c->argv[1]->ptr,"delslots")) && c->argc >= 3) {
+        int j, slot;

         unsigned char *slots = zmalloc(REDIS_CLUSTER_SLOTS);
         unsigned char *slots = zmalloc(REDIS_CLUSTER_SLOTS);

+        int del = !strcasecmp(c->argv[1]->ptr,"delslots");

 
         memset(slots,0,REDIS_CLUSTER_SLOTS);
         /* Check that all the arguments are parsable and that all the
          * slots are not already busy. */
         for (j = 2; j < c->argc; j++) {
 
         memset(slots,0,REDIS_CLUSTER_SLOTS);
         /* Check that all the arguments are parsable and that all the
          * slots are not already busy. */
         for (j = 2; j < c->argc; j++) {

-            if (getLongLongFromObject(c->argv[j],&slot) != REDIS_OK ||
-                slot < 0 || slot > REDIS_CLUSTER_SLOTS)
-            {
-                addReplyError(c,"Invalid or out of range slot index");
+            if ((slot = getSlotOrReply(c,c->argv[j])) == -1) {

                 zfree(slots);
                 return;
             }
                 zfree(slots);
                 return;
             }

-            if (server.cluster.slots[slot]) {
-                addReplyErrorFormat(c,"Slot %lld is already busy", slot);
+            if (del && server.cluster.slots[slot] == NULL) {
+                addReplyErrorFormat(c,"Slot %d is already unassigned", slot);
+                zfree(slots);
+                return;
+            } else if (!del && server.cluster.slots[slot]) {
+                addReplyErrorFormat(c,"Slot %d is already busy", slot);

                 zfree(slots);
                 return;
             }
                 zfree(slots);
                 return;
             }


@@ -1195,8 +1222,15 @@ void clusterCommand(redisClient *c) {
         }
         for (j = 0; j < REDIS_CLUSTER_SLOTS; j++) {
             if (slots[j]) {
         }
         for (j = 0; j < REDIS_CLUSTER_SLOTS; j++) {
             if (slots[j]) {

-                int retval = clusterAddSlot(server.cluster.myself,j);
-                
+                int retval;
+
+                /* If this slot was set as importing we can clear this 
+                 * state as now we are the real owner of the slot. */
+                if (server.cluster.importing_slots_from[j])
+                    server.cluster.importing_slots_from[j] = NULL;
+
+                retval = del ? clusterDelSlot(j) :
+                               clusterAddSlot(server.cluster.myself,j);

                 redisAssert(retval == REDIS_OK);
             }
         }
                 redisAssert(retval == REDIS_OK);
             }
         }


@@ -1208,22 +1242,16 @@ void clusterCommand(redisClient *c) {
         /* SETSLOT 10 MIGRATING <instance ID> */
         /* SETSLOT 10 IMPORTING <instance ID> */
         /* SETSLOT 10 STABLE */
         /* SETSLOT 10 MIGRATING <instance ID> */
         /* SETSLOT 10 IMPORTING <instance ID> */
         /* SETSLOT 10 STABLE */

-        long long aux;
-        unsigned int slot;
+        int slot;

         clusterNode *n;
 
         clusterNode *n;
 

-        if (getLongLongFromObjectOrReply(c,c->argv[2],&aux,NULL) != REDIS_OK)
-            return;
-        if (aux < 0 || aux >= REDIS_CLUSTER_SLOTS) {
-            addReplyError(c,"Slot out of range");
-            return;
-        }
-        slot = (unsigned int) aux;
-        if (server.cluster.slots[slot] != server.cluster.myself) {
-            addReplyErrorFormat(c,"I'm not the owner of hash slot %u",slot);
-            return;
-        }
+        if ((slot = getSlotOrReply(c,c->argv[2])) == -1) return;
+

         if (!strcasecmp(c->argv[3]->ptr,"migrating") && c->argc == 5) {
         if (!strcasecmp(c->argv[3]->ptr,"migrating") && c->argc == 5) {

+            if (server.cluster.slots[slot] != server.cluster.myself) {
+                addReplyErrorFormat(c,"I'm not the owner of hash slot %u",slot);
+                return;
+            }

             if ((n = clusterLookupNode(c->argv[4]->ptr)) == NULL) {
                 addReplyErrorFormat(c,"I don't know about node %s",
                     (char*)c->argv[4]->ptr);
             if ((n = clusterLookupNode(c->argv[4]->ptr)) == NULL) {
                 addReplyErrorFormat(c,"I don't know about node %s",
                     (char*)c->argv[4]->ptr);


@@ -1231,6 +1259,11 @@ void clusterCommand(redisClient *c) {
             }
             server.cluster.migrating_slots_to[slot] = n;
         } else if (!strcasecmp(c->argv[3]->ptr,"importing") && c->argc == 5) {
             }
             server.cluster.migrating_slots_to[slot] = n;
         } else if (!strcasecmp(c->argv[3]->ptr,"importing") && c->argc == 5) {

+            if (server.cluster.slots[slot] == server.cluster.myself) {
+                addReplyErrorFormat(c,
+                    "I'm already the owner of hash slot %u",slot);
+                return;
+            }

             if ((n = clusterLookupNode(c->argv[4]->ptr)) == NULL) {
                 addReplyErrorFormat(c,"I don't know about node %s",
                     (char*)c->argv[3]->ptr);
             if ((n = clusterLookupNode(c->argv[4]->ptr)) == NULL) {
                 addReplyErrorFormat(c,"I don't know about node %s",
                     (char*)c->argv[3]->ptr);


@@ -1238,9 +1271,43 @@ void clusterCommand(redisClient *c) {
             }
             server.cluster.importing_slots_from[slot] = n;
         } else if (!strcasecmp(c->argv[3]->ptr,"stable") && c->argc == 4) {
             }
             server.cluster.importing_slots_from[slot] = n;
         } else if (!strcasecmp(c->argv[3]->ptr,"stable") && c->argc == 4) {

+            /* CLUSTER SETSLOT <SLOT> STABLE */

             server.cluster.importing_slots_from[slot] = NULL;
             server.cluster.importing_slots_from[slot] = NULL;

+            server.cluster.migrating_slots_to[slot] = NULL;
+        } else if (!strcasecmp(c->argv[3]->ptr,"node") && c->argc == 4) {
+            /* CLUSTER SETSLOT <SLOT> NODE <NODE ID> */
+            clusterNode *n = clusterLookupNode(c->argv[4]->ptr);
+
+            if (!n) addReplyErrorFormat(c,"Unknown node %s",
+                (char*)c->argv[4]->ptr);
+            /* If this hash slot was served by 'myself' before to switch
+             * make sure there are no longer local keys for this hash slot. */
+            if (server.cluster.slots[slot] == server.cluster.myself &&
+                n != server.cluster.myself)
+            {
+                int numkeys;
+                robj **keys;
+
+                keys = zmalloc(sizeof(robj*)*1);
+                numkeys = GetKeysInSlot(slot, keys, 1);
+                zfree(keys);
+                if (numkeys == 0) {
+                    addReplyErrorFormat(c, "Can't assign hashslot %d to a different node while I still hold keys for this hash slot.", slot);
+                    return;
+                }
+            }
+            /* If this node was the slot owner and the slot was marked as
+             * migrating, assigning the slot to another node will clear
+             * the migratig status. */
+            if (server.cluster.slots[slot] == server.cluster.myself &&
+                server.cluster.migrating_slots_to[slot])
+                server.cluster.migrating_slots_to[slot] = NULL;
+
+            clusterDelSlot(slot);
+            clusterAddSlot(n,slot);

         } else {
             addReplyError(c,"Invalid CLUSTER SETSLOT action or number of arguments");
         } else {
             addReplyError(c,"Invalid CLUSTER SETSLOT action or number of arguments");

+            return;

         }
         clusterSaveConfigOrDie();
         addReply(c,shared.ok);
         }
         clusterSaveConfigOrDie();
         addReply(c,shared.ok);


@@ -1605,12 +1672,19 @@ file_rd_err:
 /* Return the pointer to the cluster node that is able to serve the query
  * as all the keys belong to hash slots for which the node is in charge.
  *
 /* Return the pointer to the cluster node that is able to serve the query
  * as all the keys belong to hash slots for which the node is in charge.
  *

- * If keys in query spawn multiple nodes NULL is returned. */
-clusterNode *getNodeByQuery(redisClient *c, struct redisCommand *cmd, robj **argv, int argc, int *hashslot) {
+ * If the returned node should be used only for this request, the *ask
+ * integer is set to '1', otherwise to '0'. This is used in order to
+ * let the caller know if we should reply with -MOVED or with -ASK.
+ *
+ * If the request contains more than a single key NULL is returned,
+ * however a request with more then a key argument where the key is always
+ * the same is valid, like in: RPOPLPUSH mylist mylist.*/
+clusterNode *getNodeByQuery(redisClient *c, struct redisCommand *cmd, robj **argv, int argc, int *hashslot, int *ask) {

     clusterNode *n = NULL;
     clusterNode *n = NULL;

+    robj *firstkey = NULL;

     multiState *ms, _ms;
     multiCmd mc;
     multiState *ms, _ms;
     multiCmd mc;

-    int i;
+    int i, slot = 0;

 
     /* We handle all the cases as if they were EXEC commands, so we have
      * a common code path for everything */
 
     /* We handle all the cases as if they were EXEC commands, so we have
      * a common code path for everything */


@@ -1620,7 +1694,9 @@ clusterNode *getNodeByQuery(redisClient *c, struct redisCommand *cmd, robj **arg
         if (!(c->flags & REDIS_MULTI)) return server.cluster.myself;
         ms = &c->mstate;
     } else {
         if (!(c->flags & REDIS_MULTI)) return server.cluster.myself;
         ms = &c->mstate;
     } else {

-        /* Create a fake Multi State structure, with just one command */
+        /* In order to have a single codepath create a fake Multi State
+         * structure if the client is not in MULTI/EXEC state, this way
+         * we have a single codepath below. */

         ms = &_ms;
         _ms.commands = &mc;
         _ms.count = 1;
         ms = &_ms;
         _ms.commands = &mc;
         _ms.count = 1;


@@ -1629,6 +1705,8 @@ clusterNode *getNodeByQuery(redisClient *c, struct redisCommand *cmd, robj **arg
         mc.cmd = cmd;
     }
 
         mc.cmd = cmd;
     }
 

+    /* Check that all the keys are the same key, and get the slot and
+     * node for this key. */

     for (i = 0; i < ms->count; i++) {
         struct redisCommand *mcmd;
         robj **margv;
     for (i = 0; i < ms->count; i++) {
         struct redisCommand *mcmd;
         robj **margv;


@@ -1639,26 +1717,50 @@ clusterNode *getNodeByQuery(redisClient *c, struct redisCommand *cmd, robj **arg
         margv = ms->commands[i].argv;
 
         keyindex = getKeysFromCommand(mcmd,margv,margc,&numkeys,
         margv = ms->commands[i].argv;
 
         keyindex = getKeysFromCommand(mcmd,margv,margc,&numkeys,

-                                      REDIS_GETKEYS_PRELOAD);
+                                      REDIS_GETKEYS_ALL);

         for (j = 0; j < numkeys; j++) {
         for (j = 0; j < numkeys; j++) {

-            int slot = keyHashSlot((char*)margv[keyindex[j]]->ptr,
-                sdslen(margv[keyindex[j]]->ptr));
-            struct clusterNode *slotnode;
-
-            slotnode = server.cluster.slots[slot];
-            if (hashslot) *hashslot = slot;
-            /* Node not assigned? (Should never happen actually
-             * if we reached this function).
-             * Different node than the previous one?
-             * Return NULL, the cluster can't serve multi-node requests */
-            if (slotnode == NULL || (n && slotnode != n)) {
-                getKeysFreeResult(keyindex);
-                return NULL;
+            if (firstkey == NULL) {
+                /* This is the first key we see. Check what is the slot
+                 * and node. */
+                firstkey = margv[keyindex[j]];
+
+                slot = keyHashSlot((char*)firstkey->ptr, sdslen(firstkey->ptr));
+                n = server.cluster.slots[slot];
+                redisAssert(n != NULL);

             } else {
             } else {

-                n = slotnode;
+                /* If it is not the first key, make sure it is exactly
+                 * the same key as the first we saw. */
+                if (!equalStringObjects(firstkey,margv[keyindex[j]])) {
+                    decrRefCount(firstkey);
+                    getKeysFreeResult(keyindex);
+                    return NULL;
+                }

             }
         }
         getKeysFreeResult(keyindex);
     }
             }
         }
         getKeysFreeResult(keyindex);
     }

-    return (n == NULL) ? server.cluster.myself : n;
+    if (ask) *ask = 0; /* This is the default. Set to 1 if needed later. */
+    /* No key at all in command? then we can serve the request
+     * without redirections. */
+    if (n == NULL) return server.cluster.myself;
+    if (hashslot) *hashslot = slot;
+    /* This request is about a slot we are migrating into another instance?
+     * Then we need to check if we have the key. If we have it we can reply.
+     * If instead is a new key, we pass the request to the node that is
+     * receiving the slot. */
+    if (n == server.cluster.myself &&
+        server.cluster.migrating_slots_to[slot] != NULL)
+    {
+        if (lookupKeyRead(&server.db[0],firstkey) == NULL) {
+            if (ask) *ask = 1;
+            return server.cluster.migrating_slots_to[slot];
+        }
+    }
+    /* Handle the case in which we are receiving this hash slot from
+     * another instance, so we'll accept the query even if in the table
+     * it is assigned to a different node. */
+    if (server.cluster.importing_slots_from[slot] != NULL)
+        return server.cluster.myself;
+    /* It's not a -ASK case. Base case: just return the right node. */
+    return n;

 }
 }