From c36fca52f5e4594ffd0ff175b328966b0d393184 Mon Sep 17 00:00:00 2001 From: Andy Adamson Date: Thu, 6 Jan 2011 02:04:32 +0000 Subject: NFS refactor nfs_find_client and reference client across callback processing Fixes a bug where the nfs_client could be freed during callback processing. Refactor nfs_find_client to use minorversion specific means to locate the correct nfs_client structure. In the NFS layer, V4.0 clients are found using the callback_ident field in the CB_COMPOUND header. V4.1 clients are found using the sessionID in the CB_SEQUENCE operation which is also compared against the sessionID associated with the back channel thread after a successful CREATE_SESSION. Each of these methods finds the one an only nfs_client associated with the incoming callback request - so nfs_find_client_next is not needed. In the RPC layer, the pg_authenticate call needs to find the nfs_client. For the v4.0 callback service, the callback identifier has not been decoded so a search by address, version, and minorversion is used. The sessionid for the sessions based callback service has (usually) not been set for the pg_authenticate on a CB_NULL call which can be sent prior to the return of a CREATE_SESSION call, so the sessionid associated with the back channel thread is not used to find the client in pg_authenticate for CB_NULL calls. Pass the referenced nfs_client to each CB_COMPOUND operation being proceesed via the new cb_process_state structure. The reference is held across cb_compound processing. Use the new cb_process_state struct to move the NFS4ERR_RETRY_UNCACHED_REP processing from process_op into nfs4_callback_sequence where it belongs. Signed-off-by: Andy Adamson Signed-off-by: Trond Myklebust --- fs/nfs/callback.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) (limited to 'fs/nfs/callback.c') diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c index c0b05497972b..15677e7bede5 100644 --- a/fs/nfs/callback.c +++ b/fs/nfs/callback.c @@ -16,9 +16,7 @@ #include #include #include -#if defined(CONFIG_NFS_V4_1) #include -#endif #include @@ -384,6 +382,23 @@ static int check_gss_callback_principal(struct nfs_client *clp, return SVC_OK; } +/* pg_authenticate method helper */ +static struct nfs_client *nfs_cb_find_client(struct svc_rqst *rqstp) +{ + struct nfs4_sessionid *sessionid = bc_xprt_sid(rqstp); + int is_cb_compound = rqstp->rq_proc == CB_COMPOUND ? 1 : 0; + + dprintk("--> %s rq_proc %d\n", __func__, rqstp->rq_proc); + if (svc_is_backchannel(rqstp)) + /* Sessionid (usually) set after CB_NULL ping */ + return nfs4_find_client_sessionid(svc_addr(rqstp), sessionid, + is_cb_compound); + else + /* No callback identifier in pg_authenticate */ + return nfs4_find_client_no_ident(svc_addr(rqstp)); +} + +/* pg_authenticate method for nfsv4 callback threads. */ static int nfs_callback_authenticate(struct svc_rqst *rqstp) { struct nfs_client *clp; @@ -391,7 +406,7 @@ static int nfs_callback_authenticate(struct svc_rqst *rqstp) int ret = SVC_OK; /* Don't talk to strangers */ - clp = nfs_find_client(svc_addr(rqstp), 4); + clp = nfs_cb_find_client(rqstp); if (clp == NULL) return SVC_DROP; -- cgit v1.2.3