Commit bbb9db5e authored by Shyam Prasad N's avatar Shyam Prasad N Committed by Steve French
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cifs: avoid use of dstaddr as key for fscache client cookie 



server->dstaddr can change when the DNS mapping for the
server hostname changes. But conn_id is a u64 counter
that is incremented each time a new TCP connection
is setup. So use only that as a key.

Signed-off-by: default avatarShyam Prasad N <sprasad@microsoft.com>
Reviewed-by: default avatarPaulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 2adc8200

fs/cifs/fscache.c

+1 −37
Original line number Diff line number Diff line
@@ -16,14 +16,6 @@ 
 * Key layout of CIFS server cache index object

 */

struct cifs_server_key {

	struct {

		uint16_t	family;		/* address family */

		__be16		port;		/* IP port */

	} hdr;

	union {

		struct in_addr	ipv4_addr;

		struct in6_addr	ipv6_addr;

	};

	__u64 conn_id;

} __packed;
@@ -32,11 +24,7 @@ struct cifs_server_key { 
 */

void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server)

{

	const struct sockaddr *sa = (struct sockaddr *) &server->dstaddr;

	const struct sockaddr_in *addr = (struct sockaddr_in *) sa;

	const struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) sa;

	struct cifs_server_key key;

	uint16_t key_len = sizeof(key.hdr);



	/*

	 * Check if cookie was already initialized so don't reinitialize it.
@@ -47,36 +35,12 @@ void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) 
		return;



	memset(&key, 0, sizeof(key));



	/*

	 * Should not be a problem as sin_family/sin6_family overlays

	 * sa_family field

	 */

	key.hdr.family = sa->sa_family;

	switch (sa->sa_family) {

	case AF_INET:

		key.hdr.port = addr->sin_port;

		key.ipv4_addr = addr->sin_addr;

		key_len += sizeof(key.ipv4_addr);

		break;



	case AF_INET6:

		key.hdr.port = addr6->sin6_port;

		key.ipv6_addr = addr6->sin6_addr;

		key_len += sizeof(key.ipv6_addr);

		break;



	default:

		cifs_dbg(VFS, "Unknown network family '%d'\n", sa->sa_family);

		server->fscache = NULL;

		return;

	}

	key.conn_id = server->conn_id;



	server->fscache =

		fscache_acquire_cookie(cifs_fscache_netfs.primary_index,

				       &cifs_fscache_server_index_def,

				       &key, key_len,

				       &key, sizeof(key),

				       NULL, 0,

				       server, 0, true);

	cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",