[PATCH] lockd: remove hardcoded maximum NLM cookie length

At the moment, the NLM cookie length is fixed to 8 bytes, while 1024 is the
theoretical maximum.  FreeBSD uses 16 bytes, Mac OS X uses 20 bytes. 
Therefore we need to make the length dynamic (which I set to 32 bytes).

This patch is based on an old patch for Linux 2.4.23-pre9, which I changed
to patch properly (also added some stylish NIPQUAD fixes).

From: Neil Brown <neilb@cse.unsw.edu.au>

Further lockd tidyups.
  - NIPQUAD everywhere that is appropriate
  - use XDR_QUADLEN in more places as appropriate
  - discard QUADLEN which is a lockd-specific version of XDR_QUADLEN
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/lockd/host.c

@@ -104,11 +104,7 @@ nlm_lookup_host(int server, struct sockaddr_in *sin,
 	memset(host, 0, sizeof(*host));
 
 	addr = sin->sin_addr.s_addr;
-	sprintf(host->h_name, "%d.%d.%d.%d",
-			(unsigned char) (ntohl(addr) >> 24),
-			(unsigned char) (ntohl(addr) >> 16),
-			(unsigned char) (ntohl(addr) >>  8),
-			(unsigned char) (ntohl(addr) >>  0));
+	sprintf(host->h_name, "%u.%u.%u.%u", NIPQUAD(addr));
 
 	host->h_addr       = *sin;
 	host->h_addr.sin_port = 0;	/* ouch! */

fs/lockd/mon.c

@@ -140,7 +140,6 @@ static u32 *
 xdr_encode_common(struct rpc_rqst *rqstp, u32 *p, struct nsm_args *argp)
 {
 	char	buffer[20];
-	u32	addr = ntohl(argp->addr);
 
 	/*
 	 * Use the dotted-quad IP address of the remote host as
@@ -148,8 +147,7 @@ xdr_encode_common(struct rpc_rqst *rqstp, u32 *p, struct nsm_args *argp)
 	 * hostname first for whatever remote hostname it receives,
 	 * so this works alright.
 	 */
-	sprintf(buffer, "%d.%d.%d.%d", (addr>>24) & 0xff, (addr>>16) & 0xff,
-				 	(addr>>8) & 0xff,  (addr) & 0xff);
+	sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(argp->addr));
 	if (!(p = xdr_encode_string(p, buffer))
 	 || !(p = xdr_encode_string(p, system_utsname.nodename)))
 		return ERR_PTR(-EIO);

fs/lockd/svc4proc.c

@@ -546,10 +546,10 @@ struct nlm_void			{ int dummy; };
    .pc_ressize	= sizeof(struct nlm_##rest),		\
    .pc_xdrressize = respsize,				\
  }
-#define	Ck	(1+8)	/* cookie */
-#define	No	(1+1024/4)	/* netobj */
-#define	St	1	/* status */
-#define	Rg	4	/* range (offset + length) */
+#define	Ck	(1+XDR_QUADLEN(NLM_MAXCOOKIELEN))	/* cookie */
+#define	No	(1+1024/4)				/* netobj */
+#define	St	1					/* status */
+#define	Rg	4					/* range (offset + length) */
 struct svc_procedure		nlmsvc_procedures4[] = {
   PROC(null,		void,		void,		void,	void, 1),
   PROC(test,		testargs,	testres,	args,	res, Ck+St+2+No+Rg),

fs/lockd/svclock.c

@@ -112,11 +112,11 @@ nlmsvc_lookup_block(struct nlm_file *file, struct nlm_lock *lock, int remove)
 				(long long)lock->fl.fl_end, lock->fl.fl_type);
 	for (head = &nlm_blocked; (block = *head) != 0; head = &block->b_next) {
 		fl = &block->b_call.a_args.lock.fl;
-		dprintk("lockd: check f=%p pd=%d %Ld-%Ld ty=%d cookie=%x\n",
+		dprintk("lockd: check f=%p pd=%d %Ld-%Ld ty=%d cookie=%s\n",
 				block->b_file, fl->fl_pid,
 				(long long)fl->fl_start,
 				(long long)fl->fl_end, fl->fl_type,
-				*(unsigned int*)(block->b_call.a_args.cookie.data));
+				nlmdbg_cookie2a(&block->b_call.a_args.cookie));
 		if (block->b_file == file && nlm_compare_locks(fl, &lock->fl)) {
 			if (remove) {
 				*head = block->b_next;
@@ -584,13 +584,13 @@ nlmsvc_grant_callback(struct rpc_task *task)
 	struct sockaddr_in	*peer_addr = RPC_PEERADDR(task->tk_client);
 
 	dprintk("lockd: GRANT_MSG RPC callback\n");
-	dprintk("callback: looking for cookie %x, host (%08x)\n", 
-		*(unsigned int *)(call->a_args.cookie.data),
-		ntohl(peer_addr->sin_addr.s_addr));
+	dprintk("callback: looking for cookie %s, host (%u.%u.%u.%u)\n",
+		nlmdbg_cookie2a(&call->a_args.cookie),
+		NIPQUAD(peer_addr->sin_addr.s_addr));
 	if (!(block = nlmsvc_find_block(&call->a_args.cookie, peer_addr))) {
-		dprintk("lockd: no block for cookie %x, host (%08x)\n",
-			*(u32 *)(call->a_args.cookie.data),
-			ntohl(peer_addr->sin_addr.s_addr));
+		dprintk("lockd: no block for cookie %s, host (%u.%u.%u.%u)\n",
+			nlmdbg_cookie2a(&call->a_args.cookie),
+			NIPQUAD(peer_addr->sin_addr.s_addr));
 		return;
 	}
 

fs/lockd/svcproc.c

@@ -571,10 +571,10 @@ struct nlm_void			{ int dummy; };
    .pc_xdrressize = respsize,				\
  }
 
-#define	Ck	(1+8)	/* cookie */
-#define	St	1	/* status */
-#define	No	(1+1024/4) /* Net Obj */
-#define	Rg	2	/* range - offset + size */
+#define	Ck	(1+XDR_QUADLEN(NLM_MAXCOOKIELEN))	/* cookie */
+#define	St	1				/* status */
+#define	No	(1+1024/4)			/* Net Obj */
+#define	Rg	2				/* range - offset + size */
 
 struct svc_procedure		nlmsvc_procedures[] = {
   PROC(null,		void,		void,		void,	void, 1),

fs/lockd/xdr.c

@@ -55,16 +55,16 @@ static inline u32 *nlm_decode_cookie(u32 *p, struct nlm_cookie *c)
 		c->len=4;
 		memset(c->data, 0, 4);	/* hockeypux brain damage */
 	}
-	else if(len<=8)
+	else if(len<=NLM_MAXCOOKIELEN)
 	{
 		c->len=len;
 		memcpy(c->data, p, len);
-		p+=(len+3)>>2;
+		p+=XDR_QUADLEN(len);
 	}
 	else 
 	{
 		printk(KERN_NOTICE
-			"lockd: bad cookie size %d (only cookies under 8 bytes are supported.)\n", len);
+			"lockd: bad cookie size %d (only cookies under %d bytes are supported.)\n", len, NLM_MAXCOOKIELEN);
 		return NULL;
 	}
 	return p;
@@ -75,7 +75,7 @@ nlm_encode_cookie(u32 *p, struct nlm_cookie *c)
 {
 	*p++ = htonl(c->len);
 	memcpy(p, c->data, c->len);
-	p+=(c->len+3)>>2;
+	p+=XDR_QUADLEN(c->len);
 	return p;
 }
 
@@ -86,7 +86,7 @@ nlm_decode_fh(u32 *p, struct nfs_fh *f)
 
 	if ((len = ntohl(*p++)) != NFS2_FHSIZE) {
 		printk(KERN_NOTICE
-			"lockd: bad fhandle size %x (should be %d)\n",
+			"lockd: bad fhandle size %d (should be %d)\n",
 			len, NFS2_FHSIZE);
 		return NULL;
 	}
@@ -512,11 +512,11 @@ nlmclt_decode_res(struct rpc_rqst *req, u32 *p, struct nlm_res *resp)
  * Buffer requirements for NLM
  */
 #define NLM_void_sz		0
-#define NLM_cookie_sz		3	/* 1 len , 2 data */
-#define NLM_caller_sz		1+QUADLEN(sizeof(system_utsname.nodename))
-#define NLM_netobj_sz		1+QUADLEN(XDR_MAX_NETOBJ)
-/* #define NLM_owner_sz		1+QUADLEN(NLM_MAXOWNER) */
-#define NLM_fhandle_sz		1+QUADLEN(NFS2_FHSIZE)
+#define NLM_cookie_sz		1+XDR_QUADLEN(NLM_MAXCOOKIELEN)
+#define NLM_caller_sz		1+XDR_QUADLEN(sizeof(system_utsname.nodename))
+#define NLM_netobj_sz		1+XDR_QUADLEN(XDR_MAX_NETOBJ)
+/* #define NLM_owner_sz		1+XDR_QUADLEN(NLM_MAXOWNER) */
+#define NLM_fhandle_sz		1+XDR_QUADLEN(NFS2_FHSIZE)
 #define NLM_lock_sz		3+NLM_caller_sz+NLM_netobj_sz+NLM_fhandle_sz
 #define NLM_holder_sz		4+NLM_netobj_sz
 
@@ -604,3 +604,32 @@ struct rpc_program		nlm_program = {
 		.stats		= &nlm_stats,
 };
 
+#ifdef RPC_DEBUG
+const char *nlmdbg_cookie2a(const struct nlm_cookie *cookie)
+{
+	/*
+	 * We can get away with a static buffer because we're only
+	 * called with BKL held.
+	 */
+	static char buf[2*NLM_MAXCOOKIELEN+1];
+	int i;
+	int len = sizeof(buf);
+	char *p = buf;
+
+	len--;	/* allow for trailing \0 */
+	if (len < 3)
+		return "???";
+	for (i = 0 ; i < cookie->len ; i++) {
+		if (len < 2) {
+			strcpy(p-3, "...");
+			break;
+		}
+		sprintf(p, "%02x", cookie->data[i]);
+		p += 2;
+		len -= 2;
+	}
+	*p = '\0';
+
+	return buf;
+}
+#endif

fs/lockd/xdr4.c

@@ -56,16 +56,16 @@ nlm4_decode_cookie(u32 *p, struct nlm_cookie *c)
 		c->len=4;
 		memset(c->data, 0, 4);	/* hockeypux brain damage */
 	}
-	else if(len<=8)
+	else if(len<=NLM_MAXCOOKIELEN)
 	{
 		c->len=len;
 		memcpy(c->data, p, len);
-		p+=(len+3)>>2;
+		p+=XDR_QUADLEN(len);
 	}
 	else 
 	{
 		printk(KERN_NOTICE
-			"lockd: bad cookie size %d (only cookies under 8 bytes are supported.)\n", len);
+			"lockd: bad cookie size %d (only cookies under %d bytes are supported.)\n", len, NLM_MAXCOOKIELEN);
 		return NULL;
 	}
 	return p;
@@ -76,7 +76,7 @@ nlm4_encode_cookie(u32 *p, struct nlm_cookie *c)
 {
 	*p++ = htonl(c->len);
 	memcpy(p, c->data, c->len);
-	p+=(c->len+3)>>2;
+	p+=XDR_QUADLEN(c->len);
 	return p;
 }
 
@@ -515,7 +515,7 @@ nlm4clt_decode_res(struct rpc_rqst *req, u32 *p, struct nlm_res *resp)
  * Buffer requirements for NLM
  */
 #define NLM4_void_sz		0
-#define NLM4_cookie_sz		3	/* 1 len , 2 data */
+#define NLM4_cookie_sz		1+XDR_QUADLEN(NLM_MAXCOOKIELEN)
 #define NLM4_caller_sz		1+XDR_QUADLEN(NLM_MAXSTRLEN)
 #define NLM4_netobj_sz		1+XDR_QUADLEN(XDR_MAX_NETOBJ)
 /* #define NLM4_owner_sz		1+XDR_QUADLEN(NLM4_MAXOWNER) */

include/linux/lockd/debug.h

@@ -45,4 +45,13 @@
 #define NLMDBG_ALL		0x7fff
 
 
+/*
+ * Support for printing NLM cookies in dprintk()
+ */
+#ifdef RPC_DEBUG
+struct nlm_cookie;
+/* Call this function with the BKL held (it uses a static buffer) */
+extern const char *nlmdbg_cookie2a(const struct nlm_cookie *);
+#endif
+
 #endif /* LINUX_LOCKD_DEBUG_H */

include/linux/lockd/xdr.h

@@ -13,10 +13,9 @@
 #include <linux/nfs.h>
 #include <linux/sunrpc/xdr.h>
 
+#define NLM_MAXCOOKIELEN    	32
 #define NLM_MAXSTRLEN		1024
 
-#define QUADLEN(len)		(((len) + 3) >> 2)
-
 #define	nlm_granted		__constant_htonl(NLM_LCK_GRANTED)
 #define	nlm_lck_denied		__constant_htonl(NLM_LCK_DENIED)
 #define	nlm_lck_denied_nolocks	__constant_htonl(NLM_LCK_DENIED_NOLOCKS)
@@ -33,13 +32,14 @@ struct nlm_lock {
 };
 
 /*
- *	NLM cookies. Technically they can be 1K, Nobody uses over 8 bytes
- *	however.
+ *	NLM cookies. Technically they can be 1K, but Linux only uses 8 bytes.
+ *	FreeBSD uses 16, Apple Mac OS X 10.3 uses 20. Therefore we set it to
+ *	32 bytes.
  */
  
 struct nlm_cookie
 {
-	unsigned char data[8];
+	unsigned char data[NLM_MAXCOOKIELEN];
 	unsigned int len;
 };