Fix nobh_truncate_page() to not pass stack garbage to get_block()
[safe/jmp/linux-2.6] / fs / lockd / host.c
index be8f19d..99d737b 100644 (file)
@@ -15,7 +15,6 @@
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/svc.h>
 #include <linux/lockd/lockd.h>
-#include <linux/lockd/sm_inter.h>
 #include <linux/mutex.h>
 
 #include <net/ipv6.h>
@@ -32,11 +31,19 @@ static int                  nrhosts;
 static DEFINE_MUTEX(nlm_host_mutex);
 
 static void                    nlm_gc_hosts(void);
-static struct nsm_handle       *nsm_find(const struct sockaddr *sap,
-                                               const size_t salen,
-                                               const char *hostname,
-                                               const size_t hostname_len,
-                                               const int create);
+
+struct nlm_lookup_host_info {
+       const int               server;         /* search for server|client */
+       const struct sockaddr   *sap;           /* address to search for */
+       const size_t            salen;          /* it's length */
+       const unsigned short    protocol;       /* transport to search for*/
+       const u32               version;        /* NLM version to search for */
+       const char              *hostname;      /* remote's hostname */
+       const size_t            hostname_len;   /* it's length */
+       const struct sockaddr   *src_sap;       /* our address (optional) */
+       const size_t            src_len;        /* it's length */
+       const int               noresvport;     /* use non-priv port */
+};
 
 /*
  * Hash function must work well on big- and little-endian platforms
@@ -92,52 +99,16 @@ static void nlm_clear_port(struct sockaddr *sap)
        }
 }
 
-static void nlm_display_address(const struct sockaddr *sap,
-                               char *buf, const size_t len)
-{
-       const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
-       const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
-
-       switch (sap->sa_family) {
-       case AF_UNSPEC:
-               snprintf(buf, len, "unspecified");
-               break;
-       case AF_INET:
-               snprintf(buf, len, NIPQUAD_FMT, NIPQUAD(sin->sin_addr.s_addr));
-               break;
-       case AF_INET6:
-               if (ipv6_addr_v4mapped(&sin6->sin6_addr))
-                       snprintf(buf, len, NIPQUAD_FMT,
-                                NIPQUAD(sin6->sin6_addr.s6_addr32[3]));
-               else
-                       snprintf(buf, len, NIP6_FMT, NIP6(sin6->sin6_addr));
-               break;
-       default:
-               snprintf(buf, len, "unsupported address family");
-               break;
-       }
-}
-
 /*
  * Common host lookup routine for server & client
  */
-static struct nlm_host *nlm_lookup_host(int server,
-                                       const struct sockaddr_in *sin,
-                                       int proto, u32 version,
-                                       const char *hostname,
-                                       unsigned int hostname_len,
-                                       const struct sockaddr_in *ssin)
+static struct nlm_host *nlm_lookup_host(struct nlm_lookup_host_info *ni)
 {
        struct hlist_head *chain;
        struct hlist_node *pos;
        struct nlm_host *host;
        struct nsm_handle *nsm = NULL;
 
-       dprintk("lockd: nlm_lookup_host(proto=%d, vers=%u,"
-                       " my role is %s, hostname=%.*s)\n",
-                       proto, version, server ? "server" : "client",
-                       hostname_len, hostname ? hostname : "<none>");
-
        mutex_lock(&nlm_host_mutex);
 
        if (time_after_eq(jiffies, next_gc))
@@ -150,22 +121,23 @@ static struct nlm_host *nlm_lookup_host(int server,
         * different NLM rpc_clients into one single nlm_host object.
         * This would allow us to have one nlm_host per address.
         */
-       chain = &nlm_hosts[nlm_hash_address((struct sockaddr *)sin)];
+       chain = &nlm_hosts[nlm_hash_address(ni->sap)];
        hlist_for_each_entry(host, pos, chain, h_hash) {
-               if (!nlm_cmp_addr(nlm_addr(host), (struct sockaddr *)sin))
+               if (!nlm_cmp_addr(nlm_addr(host), ni->sap))
                        continue;
 
                /* See if we have an NSM handle for this client */
                if (!nsm)
                        nsm = host->h_nsmhandle;
 
-               if (host->h_proto != proto)
+               if (host->h_proto != ni->protocol)
                        continue;
-               if (host->h_version != version)
+               if (host->h_version != ni->version)
                        continue;
-               if (host->h_server != server)
+               if (host->h_server != ni->server)
                        continue;
-               if (!nlm_cmp_addr(nlm_srcaddr(host), (struct sockaddr *)ssin))
+               if (ni->server &&
+                   !nlm_cmp_addr(nlm_srcaddr(host), ni->src_sap))
                        continue;
 
                /* Move to head of hash chain. */
@@ -186,8 +158,8 @@ static struct nlm_host *nlm_lookup_host(int server,
                atomic_inc(&nsm->sm_count);
        else {
                host = NULL;
-               nsm = nsm_find((struct sockaddr *)sin, sizeof(*sin),
-                               hostname, hostname_len, 1);
+               nsm = nsm_get_handle(ni->sap, ni->salen,
+                                       ni->hostname, ni->hostname_len);
                if (!nsm) {
                        dprintk("lockd: nlm_lookup_host failed; "
                                "no nsm handle\n");
@@ -202,12 +174,13 @@ static struct nlm_host *nlm_lookup_host(int server,
                goto out;
        }
        host->h_name       = nsm->sm_name;
-       memcpy(nlm_addr(host), sin, sizeof(*sin));
-       host->h_addrlen = sizeof(*sin);
+       host->h_addrbuf    = nsm->sm_addrbuf;
+       memcpy(nlm_addr(host), ni->sap, ni->salen);
+       host->h_addrlen = ni->salen;
        nlm_clear_port(nlm_addr(host));
-       memcpy(nlm_srcaddr(host), ssin, sizeof(*ssin));
-       host->h_version    = version;
-       host->h_proto      = proto;
+       memcpy(nlm_srcaddr(host), ni->src_sap, ni->src_len);
+       host->h_version    = ni->version;
+       host->h_proto      = ni->protocol;
        host->h_rpcclnt    = NULL;
        mutex_init(&host->h_mutex);
        host->h_nextrebind = jiffies + NLM_HOST_REBIND;
@@ -218,7 +191,8 @@ static struct nlm_host *nlm_lookup_host(int server,
        host->h_state      = 0;                 /* pseudo NSM state */
        host->h_nsmstate   = 0;                 /* real NSM state */
        host->h_nsmhandle  = nsm;
-       host->h_server     = server;
+       host->h_server     = ni->server;
+       host->h_noresvport = ni->noresvport;
        hlist_add_head(&host->h_hash, chain);
        INIT_LIST_HEAD(&host->h_lockowners);
        spin_lock_init(&host->h_lock);
@@ -227,11 +201,6 @@ static struct nlm_host *nlm_lookup_host(int server,
 
        nrhosts++;
 
-       nlm_display_address((struct sockaddr *)&host->h_addr,
-                               host->h_addrbuf, sizeof(host->h_addrbuf));
-       nlm_display_address((struct sockaddr *)&host->h_srcaddr,
-                               host->h_srcaddrbuf, sizeof(host->h_srcaddrbuf));
-
        dprintk("lockd: nlm_lookup_host created host %s\n",
                        host->h_name);
 
@@ -251,10 +220,8 @@ nlm_destroy_host(struct nlm_host *host)
        BUG_ON(!list_empty(&host->h_lockowners));
        BUG_ON(atomic_read(&host->h_count));
 
-       /*
-        * Release NSM handle and unmonitor host.
-        */
        nsm_unmonitor(host);
+       nsm_release(host->h_nsmhandle);
 
        clnt = host->h_rpcclnt;
        if (clnt != NULL)
@@ -262,37 +229,107 @@ nlm_destroy_host(struct nlm_host *host)
        kfree(host);
 }
 
-/*
- * Find an NLM server handle in the cache. If there is none, create it.
+/**
+ * nlmclnt_lookup_host - Find an NLM host handle matching a remote server
+ * @sap: network address of server
+ * @salen: length of server address
+ * @protocol: transport protocol to use
+ * @version: NLM protocol version
+ * @hostname: '\0'-terminated hostname of server
+ * @noresvport: 1 if non-privileged port should be used
+ *
+ * Returns an nlm_host structure that matches the passed-in
+ * [server address, transport protocol, NLM version, server hostname].
+ * If one doesn't already exist in the host cache, a new handle is
+ * created and returned.
  */
-struct nlm_host *nlmclnt_lookup_host(const struct sockaddr_in *sin,
-                                    int proto, u32 version,
+struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap,
+                                    const size_t salen,
+                                    const unsigned short protocol,
+                                    const u32 version,
                                     const char *hostname,
-                                    unsigned int hostname_len)
+                                    int noresvport)
 {
-       const struct sockaddr_in source = {
-               .sin_family     = AF_UNSPEC,
+       const struct sockaddr source = {
+               .sa_family      = AF_UNSPEC,
        };
+       struct nlm_lookup_host_info ni = {
+               .server         = 0,
+               .sap            = sap,
+               .salen          = salen,
+               .protocol       = protocol,
+               .version        = version,
+               .hostname       = hostname,
+               .hostname_len   = strlen(hostname),
+               .src_sap        = &source,
+               .src_len        = sizeof(source),
+               .noresvport     = noresvport,
+       };
+
+       dprintk("lockd: %s(host='%s', vers=%u, proto=%s)\n", __func__,
+                       (hostname ? hostname : "<none>"), version,
+                       (protocol == IPPROTO_UDP ? "udp" : "tcp"));
 
-       return nlm_lookup_host(0, sin, proto, version,
-                              hostname, hostname_len, &source);
+       return nlm_lookup_host(&ni);
 }
 
-/*
- * Find an NLM client handle in the cache. If there is none, create it.
+/**
+ * nlmsvc_lookup_host - Find an NLM host handle matching a remote client
+ * @rqstp: incoming NLM request
+ * @hostname: name of client host
+ * @hostname_len: length of client hostname
+ *
+ * Returns an nlm_host structure that matches the [client address,
+ * transport protocol, NLM version, client hostname] of the passed-in
+ * NLM request.  If one doesn't already exist in the host cache, a
+ * new handle is created and returned.
+ *
+ * Before possibly creating a new nlm_host, construct a sockaddr
+ * for a specific source address in case the local system has
+ * multiple network addresses.  The family of the address in
+ * rq_daddr is guaranteed to be the same as the family of the
+ * address in rq_addr, so it's safe to use the same family for
+ * the source address.
  */
-struct nlm_host *
-nlmsvc_lookup_host(struct svc_rqst *rqstp,
-                       const char *hostname, unsigned int hostname_len)
+struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
+                                   const char *hostname,
+                                   const size_t hostname_len)
 {
-       const struct sockaddr_in source = {
+       struct sockaddr_in sin = {
                .sin_family     = AF_INET,
-               .sin_addr       = rqstp->rq_daddr.addr,
        };
+       struct sockaddr_in6 sin6 = {
+               .sin6_family    = AF_INET6,
+       };
+       struct nlm_lookup_host_info ni = {
+               .server         = 1,
+               .sap            = svc_addr(rqstp),
+               .salen          = rqstp->rq_addrlen,
+               .protocol       = rqstp->rq_prot,
+               .version        = rqstp->rq_vers,
+               .hostname       = hostname,
+               .hostname_len   = hostname_len,
+               .src_len        = rqstp->rq_addrlen,
+       };
+
+       dprintk("lockd: %s(host='%*s', vers=%u, proto=%s)\n", __func__,
+                       (int)hostname_len, hostname, rqstp->rq_vers,
+                       (rqstp->rq_prot == IPPROTO_UDP ? "udp" : "tcp"));
+
+       switch (ni.sap->sa_family) {
+       case AF_INET:
+               sin.sin_addr.s_addr = rqstp->rq_daddr.addr.s_addr;
+               ni.src_sap = (struct sockaddr *)&sin;
+               break;
+       case AF_INET6:
+               ipv6_addr_copy(&sin6.sin6_addr, &rqstp->rq_daddr.addr6);
+               ni.src_sap = (struct sockaddr *)&sin6;
+               break;
+       default:
+               return NULL;
+       }
 
-       return nlm_lookup_host(1, svc_addr_in(rqstp),
-                              rqstp->rq_prot, rqstp->rq_vers,
-                              hostname, hostname_len, &source);
+       return nlm_lookup_host(&ni);
 }
 
 /*
@@ -303,8 +340,8 @@ nlm_bind_host(struct nlm_host *host)
 {
        struct rpc_clnt *clnt;
 
-       dprintk("lockd: nlm_bind_host %s (%s), my addr=%s\n",
-                       host->h_name, host->h_addrbuf, host->h_srcaddrbuf);
+       dprintk("lockd: nlm_bind_host %s (%s)\n",
+                       host->h_name, host->h_addrbuf);
 
        /* Lock host handle */
        mutex_lock(&host->h_mutex);
@@ -348,6 +385,8 @@ nlm_bind_host(struct nlm_host *host)
                 */
                if (!host->h_server)
                        args.flags |= RPC_CLNT_CREATE_HARDRTRY;
+               if (host->h_noresvport)
+                       args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
 
                clnt = rpc_create(&args);
                if (!IS_ERR(clnt))
@@ -404,35 +443,23 @@ void nlm_release_host(struct nlm_host *host)
        }
 }
 
-/*
- * We were notified that the host indicated by address &sin
- * has rebooted.
- * Release all resources held by that peer.
+/**
+ * nlm_host_rebooted - Release all resources held by rebooted host
+ * @info: pointer to decoded results of NLM_SM_NOTIFY call
+ *
+ * We were notified that the specified host has rebooted.  Release
+ * all resources held by that peer.
  */
-void nlm_host_rebooted(const struct sockaddr_in *sin,
-                               const char *hostname,
-                               unsigned int hostname_len,
-                               u32 new_state)
+void nlm_host_rebooted(const struct nlm_reboot *info)
 {
        struct hlist_head *chain;
        struct hlist_node *pos;
        struct nsm_handle *nsm;
        struct nlm_host *host;
 
-       nsm = nsm_find((struct sockaddr *)sin, sizeof(*sin),
-                       hostname, hostname_len, 0);
-       if (nsm == NULL) {
-               dprintk("lockd: never saw rebooted peer '%.*s' before\n",
-                               hostname_len, hostname);
+       nsm = nsm_reboot_lookup(info);
+       if (unlikely(nsm == NULL))
                return;
-       }
-
-       dprintk("lockd: nlm_host_rebooted(%.*s, %s)\n",
-                       hostname_len, hostname, nsm->sm_addrbuf);
-
-       /* When reclaiming locks on this peer, make sure that
-        * we set up a new notification */
-       nsm->sm_monitored = 0;
 
        /* Mark all hosts tied to this NSM state as having rebooted.
         * We run the loop repeatedly, because we drop the host table
@@ -443,8 +470,8 @@ again:      mutex_lock(&nlm_host_mutex);
        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
                hlist_for_each_entry(host, pos, chain, h_hash) {
                        if (host->h_nsmhandle == nsm
-                        && host->h_nsmstate != new_state) {
-                               host->h_nsmstate = new_state;
+                        && host->h_nsmstate != info->state) {
+                               host->h_nsmstate = info->state;
                                host->h_state++;
 
                                nlm_get_host(host);
@@ -552,89 +579,3 @@ nlm_gc_hosts(void)
 
        next_gc = jiffies + NLM_HOST_COLLECT;
 }
-
-
-/*
- * Manage NSM handles
- */
-static LIST_HEAD(nsm_handles);
-static DEFINE_SPINLOCK(nsm_lock);
-
-static struct nsm_handle *nsm_find(const struct sockaddr *sap,
-                                  const size_t salen,
-                                  const char *hostname,
-                                  const size_t hostname_len,
-                                  const int create)
-{
-       struct nsm_handle *nsm = NULL;
-       struct nsm_handle *pos;
-
-       if (!sap)
-               return NULL;
-
-       if (hostname && memchr(hostname, '/', hostname_len) != NULL) {
-               if (printk_ratelimit()) {
-                       printk(KERN_WARNING "Invalid hostname \"%.*s\" "
-                                           "in NFS lock request\n",
-                               (int)hostname_len, hostname);
-               }
-               return NULL;
-       }
-
-retry:
-       spin_lock(&nsm_lock);
-       list_for_each_entry(pos, &nsm_handles, sm_link) {
-
-               if (hostname && nsm_use_hostnames) {
-                       if (strlen(pos->sm_name) != hostname_len
-                        || memcmp(pos->sm_name, hostname, hostname_len))
-                               continue;
-               } else if (!nlm_cmp_addr(nsm_addr(pos), sap))
-                       continue;
-               atomic_inc(&pos->sm_count);
-               kfree(nsm);
-               nsm = pos;
-               goto found;
-       }
-       if (nsm) {
-               list_add(&nsm->sm_link, &nsm_handles);
-               goto found;
-       }
-       spin_unlock(&nsm_lock);
-
-       if (!create)
-               return NULL;
-
-       nsm = kzalloc(sizeof(*nsm) + hostname_len + 1, GFP_KERNEL);
-       if (nsm == NULL)
-               return NULL;
-
-       memcpy(nsm_addr(nsm), sap, salen);
-       nsm->sm_addrlen = salen;
-       nsm->sm_name = (char *) (nsm + 1);
-       memcpy(nsm->sm_name, hostname, hostname_len);
-       nsm->sm_name[hostname_len] = '\0';
-       nlm_display_address((struct sockaddr *)&nsm->sm_addr,
-                               nsm->sm_addrbuf, sizeof(nsm->sm_addrbuf));
-       atomic_set(&nsm->sm_count, 1);
-       goto retry;
-
-found:
-       spin_unlock(&nsm_lock);
-       return nsm;
-}
-
-/*
- * Release an NSM handle
- */
-void
-nsm_release(struct nsm_handle *nsm)
-{
-       if (!nsm)
-               return;
-       if (atomic_dec_and_lock(&nsm->sm_count, &nsm_lock)) {
-               list_del(&nsm->sm_link);
-               spin_unlock(&nsm_lock);
-               kfree(nsm);
-       }
-}