From 4ae19c2dd713edb7b8ad3d4ab9d234ed5dcb6b98 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 18 Jan 2013 22:41:53 -0500 Subject: NFSv4: Fix NFSv4 reference counting for trunked sessions The reference counting in nfs4_init_client assumes wongly that it is safe for nfs4_discover_server_trunking() to return a pointer to a nfs_client prior to bumping the reference count. Signed-off-by: Trond Myklebust Cc: Chuck Lever Cc: Ben Greear Cc: stable@vger.kernel.org [>=3.7] --- fs/nfs/nfs4client.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) (limited to 'fs/nfs/nfs4client.c') diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index acc347268124..65a290a73065 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -236,11 +236,10 @@ struct nfs_client *nfs4_init_client(struct nfs_client *clp, error = nfs4_discover_server_trunking(clp, &old); if (error < 0) goto error; + nfs_put_client(clp); if (clp != old) { clp->cl_preserve_clid = true; - nfs_put_client(clp); clp = old; - atomic_inc(&clp->cl_count); } return clp; @@ -306,7 +305,7 @@ int nfs40_walk_client_list(struct nfs_client *new, .clientid = new->cl_clientid, .confirm = new->cl_confirm, }; - int status; + int status = -NFS4ERR_STALE_CLIENTID; spin_lock(&nn->nfs_client_lock); list_for_each_entry_safe(pos, n, &nn->nfs_client_list, cl_share_link) { @@ -332,28 +331,28 @@ int nfs40_walk_client_list(struct nfs_client *new, if (prev) nfs_put_client(prev); + prev = pos; status = nfs4_proc_setclientid_confirm(pos, &clid, cred); - if (status == 0) { + switch (status) { + case -NFS4ERR_STALE_CLIENTID: + break; + case 0: nfs4_swap_callback_idents(pos, new); - nfs_put_client(pos); + prev = NULL; *result = pos; dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n", __func__, pos, atomic_read(&pos->cl_count)); - return 0; - } - if (status != -NFS4ERR_STALE_CLIENTID) { - nfs_put_client(pos); - dprintk("NFS: <-- %s status = %d, no result\n", - __func__, status); - return status; + default: + goto out; } spin_lock(&nn->nfs_client_lock); - prev = pos; } + spin_unlock(&nn->nfs_client_lock); +out: /* * No matching nfs_client found. This should be impossible, * because the new nfs_client has already been added to @@ -363,9 +362,8 @@ int nfs40_walk_client_list(struct nfs_client *new, */ if (prev) nfs_put_client(prev); - spin_unlock(&nn->nfs_client_lock); - pr_err("NFS: %s Error: no matching nfs_client found\n", __func__); - return -NFS4ERR_STALE_CLIENTID; + dprintk("NFS: <-- %s status = %d\n", __func__, status); + return status; } #ifdef CONFIG_NFS_V4_1 @@ -473,6 +471,7 @@ int nfs41_walk_client_list(struct nfs_client *new, if (!nfs4_match_serverowners(pos, new)) continue; + atomic_inc(&pos->cl_count); spin_unlock(&nn->nfs_client_lock); dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n", __func__, pos, atomic_read(&pos->cl_count)); -- cgit v1.2.3 From 202c312dba7d95b96493b412c606163a0cd83984 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 18 Jan 2013 22:56:23 -0500 Subject: NFSv4: Fix NFSv4 trunking discovery If walking the list in nfs4[01]_walk_client_list fails, then the most likely explanation is that the server dropped the clientid before we actually managed to confirm it. As long as our nfs_client is the very last one in the list to be tested, the caller can be assured that this is the case when the final return value is NFS4ERR_STALE_CLIENTID. Reported-by: Ben Greear Signed-off-by: Trond Myklebust Cc: Chuck Lever Cc: stable@vger.kernel.org [>=3.7] Tested-by: Ben Greear --- fs/nfs/nfs4client.c | 26 +++++++------------------- fs/nfs/nfs4state.c | 8 ++------ 2 files changed, 9 insertions(+), 25 deletions(-) (limited to 'fs/nfs/nfs4client.c') diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index 65a290a73065..2f21f17fb16c 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -352,14 +352,8 @@ int nfs40_walk_client_list(struct nfs_client *new, } spin_unlock(&nn->nfs_client_lock); + /* No match found. The server lost our clientid */ out: - /* - * No matching nfs_client found. This should be impossible, - * because the new nfs_client has already been added to - * nfs_client_list by nfs_get_client(). - * - * Don't BUG(), since the caller is holding a mutex. - */ if (prev) nfs_put_client(prev); dprintk("NFS: <-- %s status = %d\n", __func__, status); @@ -430,7 +424,7 @@ int nfs41_walk_client_list(struct nfs_client *new, { struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id); struct nfs_client *pos, *n, *prev = NULL; - int error; + int status = -NFS4ERR_STALE_CLIENTID; spin_lock(&nn->nfs_client_lock); list_for_each_entry_safe(pos, n, &nn->nfs_client_list, cl_share_link) { @@ -446,8 +440,8 @@ int nfs41_walk_client_list(struct nfs_client *new, nfs_put_client(prev); prev = pos; - error = nfs_wait_client_init_complete(pos); - if (error < 0) { + status = nfs_wait_client_init_complete(pos); + if (status < 0) { nfs_put_client(pos); spin_lock(&nn->nfs_client_lock); continue; @@ -480,16 +474,10 @@ int nfs41_walk_client_list(struct nfs_client *new, return 0; } - /* - * No matching nfs_client found. This should be impossible, - * because the new nfs_client has already been added to - * nfs_client_list by nfs_get_client(). - * - * Don't BUG(), since the caller is holding a mutex. - */ + /* No matching nfs_client found. */ spin_unlock(&nn->nfs_client_lock); - pr_err("NFS: %s Error: no matching nfs_client found\n", __func__); - return -NFS4ERR_STALE_CLIENTID; + dprintk("NFS: <-- %s status = %d\n", __func__, status); + return status; } #endif /* CONFIG_NFS_V4_1 */ diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 9448c579d41a..f72561ca6895 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -136,16 +136,11 @@ int nfs40_discover_server_trunking(struct nfs_client *clp, clp->cl_confirm = clid.confirm; status = nfs40_walk_client_list(clp, result, cred); - switch (status) { - case -NFS4ERR_STALE_CLIENTID: - set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); - case 0: + if (status == 0) { /* Sustain the lease, even if it's empty. If the clientid4 * goes stale it's of no use for trunking discovery. */ nfs4_schedule_state_renewal(*result); - break; } - out: return status; } @@ -1863,6 +1858,7 @@ again: case -ETIMEDOUT: case -EAGAIN: ssleep(1); + case -NFS4ERR_STALE_CLIENTID: dprintk("NFS: %s after status %d, retrying\n", __func__, status); goto again; -- cgit v1.2.3 From 65436ec0c8e344d9b23302b686e418f2a7b7cf7b Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 18 Jan 2013 23:01:43 -0500 Subject: NFSv4.1: Ensure that nfs41_walk_client_list() does start lease recovery We do need to start the lease recovery thread prior to waiting for the client initialisation to complete in NFSv4.1. Signed-off-by: Trond Myklebust Cc: Chuck Lever Cc: Ben Greear Cc: stable@vger.kernel.org [>=3.7] --- fs/nfs/nfs4client.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'fs/nfs/nfs4client.c') diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index 2f21f17fb16c..2e9779b58b7a 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -440,14 +440,17 @@ int nfs41_walk_client_list(struct nfs_client *new, nfs_put_client(prev); prev = pos; + nfs4_schedule_lease_recovery(pos); status = nfs_wait_client_init_complete(pos); if (status < 0) { nfs_put_client(pos); spin_lock(&nn->nfs_client_lock); continue; } - + status = pos->cl_cons_state; spin_lock(&nn->nfs_client_lock); + if (status < 0) + continue; } if (pos->rpc_ops != new->rpc_ops) -- cgit v1.2.3