From eb96d5c97b0825d542e9c4ba5e0a22b519355166 Mon Sep 17 00:00:00 2001 From: Andy Adamson Date: Tue, 27 Nov 2012 10:34:19 -0500 Subject: SUNRPC handle EKEYEXPIRED in call_refreshresult Currently, when an RPCSEC_GSS context has expired or is non-existent and the users (Kerberos) credentials have also expired or are non-existent, the client receives the -EKEYEXPIRED error and tries to refresh the context forever. If an application is performing I/O, or other work against the share, the application hangs, and the user is not prompted to refresh/establish their credentials. This can result in a denial of service for other users. Users are expected to manage their Kerberos credential lifetimes to mitigate this issue. Move the -EKEYEXPIRED handling into the RPC layer. Try tk_cred_retry number of times to refresh the gss_context, and then return -EACCES to the application. Signed-off-by: Andy Adamson Signed-off-by: Trond Myklebust --- fs/nfs/nfs3proc.c | 6 +++--- fs/nfs/nfs4filelayout.c | 1 - fs/nfs/nfs4proc.c | 18 ------------------ fs/nfs/nfs4state.c | 23 ----------------------- fs/nfs/proc.c | 43 ------------------------------------------- net/sunrpc/clnt.c | 1 + 6 files changed, 4 insertions(+), 88 deletions(-) diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c index 69322096c32..70efb63b1e4 100644 --- a/fs/nfs/nfs3proc.c +++ b/fs/nfs/nfs3proc.c @@ -24,14 +24,14 @@ #define NFSDBG_FACILITY NFSDBG_PROC -/* A wrapper to handle the EJUKEBOX and EKEYEXPIRED error messages */ +/* A wrapper to handle the EJUKEBOX error messages */ static int nfs3_rpc_wrapper(struct rpc_clnt *clnt, struct rpc_message *msg, int flags) { int res; do { res = rpc_call_sync(clnt, msg, flags); - if (res != -EJUKEBOX && res != -EKEYEXPIRED) + if (res != -EJUKEBOX) break; freezable_schedule_timeout_killable(NFS_JUKEBOX_RETRY_TIME); res = -ERESTARTSYS; @@ -44,7 +44,7 @@ nfs3_rpc_wrapper(struct rpc_clnt *clnt, struct rpc_message *msg, int flags) static int nfs3_async_handle_jukebox(struct rpc_task *task, struct inode *inode) { - if (task->tk_status != -EJUKEBOX && task->tk_status != -EKEYEXPIRED) + if (task->tk_status != -EJUKEBOX) return 0; if (task->tk_status == -EJUKEBOX) nfs_inc_stats(inode, NFSIOS_DELAY); diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c index 1e42413fab8..194c4841033 100644 --- a/fs/nfs/nfs4filelayout.c +++ b/fs/nfs/nfs4filelayout.c @@ -179,7 +179,6 @@ static int filelayout_async_handle_error(struct rpc_task *task, break; case -NFS4ERR_DELAY: case -NFS4ERR_GRACE: - case -EKEYEXPIRED: rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX); break; case -NFS4ERR_RETRY_UNCACHED_REP: diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index a4692e97bc1..b0963aeceed 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -333,7 +333,6 @@ static int nfs4_handle_exception(struct nfs_server *server, int errorcode, struc } case -NFS4ERR_GRACE: case -NFS4ERR_DELAY: - case -EKEYEXPIRED: ret = nfs4_delay(server->client, &exception->timeout); if (ret != 0) break; @@ -1343,13 +1342,6 @@ int nfs4_open_delegation_recall(struct nfs_open_context *ctx, struct nfs4_state nfs_inode_find_state_and_recover(state->inode, stateid); nfs4_schedule_stateid_recovery(server, state); - case -EKEYEXPIRED: - /* - * User RPCSEC_GSS context has expired. - * We cannot recover this stateid now, so - * skip it and allow recovery thread to - * proceed. - */ case -ENOMEM: err = 0; goto out; @@ -3946,7 +3938,6 @@ nfs4_async_handle_error(struct rpc_task *task, const struct nfs_server *server, case -NFS4ERR_DELAY: nfs_inc_server_stats(server, NFSIOS_DELAY); case -NFS4ERR_GRACE: - case -EKEYEXPIRED: rpc_delay(task, NFS4_POLL_RETRY_MAX); task->tk_status = 0; return -EAGAIN; @@ -4946,15 +4937,6 @@ int nfs4_lock_delegation_recall(struct nfs4_state *state, struct file_lock *fl) nfs4_schedule_stateid_recovery(server, state); err = 0; goto out; - case -EKEYEXPIRED: - /* - * User RPCSEC_GSS context has expired. - * We cannot recover this stateid now, so - * skip it and allow recovery thread to - * proceed. - */ - err = 0; - goto out; case -ENOMEM: case -NFS4ERR_DENIED: /* kill_proc(fl->fl_pid, SIGLOST, 1); */ diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 78e90a80fc3..8dcbd9a0367 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1437,14 +1437,6 @@ restart: /* Mark the file as being 'closed' */ state->state = 0; break; - case -EKEYEXPIRED: - /* - * User RPCSEC_GSS context has expired. - * We cannot recover this stateid now, so - * skip it and allow recovery thread to - * proceed. - */ - break; case -NFS4ERR_ADMIN_REVOKED: case -NFS4ERR_STALE_STATEID: case -NFS4ERR_BAD_STATEID: @@ -1597,14 +1589,6 @@ static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp) nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce); } -static void nfs4_warn_keyexpired(const char *s) -{ - printk_ratelimited(KERN_WARNING "Error: state manager" - " encountered RPCSEC_GSS session" - " expired against NFSv4 server %s.\n", - s); -} - static int nfs4_recovery_handle_error(struct nfs_client *clp, int error) { switch (error) { @@ -1638,10 +1622,6 @@ static int nfs4_recovery_handle_error(struct nfs_client *clp, int error) case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION: set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state); break; - case -EKEYEXPIRED: - /* Nothing we can do */ - nfs4_warn_keyexpired(clp->cl_hostname); - break; default: dprintk("%s: failed to handle error %d for server %s\n", __func__, error, clp->cl_hostname); @@ -1758,8 +1738,6 @@ static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status) dprintk("%s: exit with error %d for server %s\n", __func__, -EPROTONOSUPPORT, clp->cl_hostname); return -EPROTONOSUPPORT; - case -EKEYEXPIRED: - nfs4_warn_keyexpired(clp->cl_hostname); case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery * in nfs4_exchange_id */ default: @@ -1912,7 +1890,6 @@ again: break; case -EKEYEXPIRED: - nfs4_warn_keyexpired(clp->cl_hostname); case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery * in nfs4_exchange_id */ status = -EKEYEXPIRED; diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c index 50a88c3546e..f084dac948e 100644 --- a/fs/nfs/proc.c +++ b/fs/nfs/proc.c @@ -46,39 +46,6 @@ #define NFSDBG_FACILITY NFSDBG_PROC -/* - * wrapper to handle the -EKEYEXPIRED error message. This should generally - * only happen if using krb5 auth and a user's TGT expires. NFSv2 doesn't - * support the NFSERR_JUKEBOX error code, but we handle this situation in the - * same way that we handle that error with NFSv3. - */ -static int -nfs_rpc_wrapper(struct rpc_clnt *clnt, struct rpc_message *msg, int flags) -{ - int res; - do { - res = rpc_call_sync(clnt, msg, flags); - if (res != -EKEYEXPIRED) - break; - freezable_schedule_timeout_killable(NFS_JUKEBOX_RETRY_TIME); - res = -ERESTARTSYS; - } while (!fatal_signal_pending(current)); - return res; -} - -#define rpc_call_sync(clnt, msg, flags) nfs_rpc_wrapper(clnt, msg, flags) - -static int -nfs_async_handle_expired_key(struct rpc_task *task) -{ - if (task->tk_status != -EKEYEXPIRED) - return 0; - task->tk_status = 0; - rpc_restart_call(task); - rpc_delay(task, NFS_JUKEBOX_RETRY_TIME); - return 1; -} - /* * Bare-bones access to getattr: this is for nfs_read_super. */ @@ -364,8 +331,6 @@ static void nfs_proc_unlink_rpc_prepare(struct rpc_task *task, struct nfs_unlink static int nfs_proc_unlink_done(struct rpc_task *task, struct inode *dir) { - if (nfs_async_handle_expired_key(task)) - return 0; nfs_mark_for_revalidate(dir); return 1; } @@ -385,8 +350,6 @@ static int nfs_proc_rename_done(struct rpc_task *task, struct inode *old_dir, struct inode *new_dir) { - if (nfs_async_handle_expired_key(task)) - return 0; nfs_mark_for_revalidate(old_dir); nfs_mark_for_revalidate(new_dir); return 1; @@ -642,9 +605,6 @@ static int nfs_read_done(struct rpc_task *task, struct nfs_read_data *data) { struct inode *inode = data->header->inode; - if (nfs_async_handle_expired_key(task)) - return -EAGAIN; - nfs_invalidate_atime(inode); if (task->tk_status >= 0) { nfs_refresh_inode(inode, data->res.fattr); @@ -671,9 +631,6 @@ static int nfs_write_done(struct rpc_task *task, struct nfs_write_data *data) { struct inode *inode = data->header->inode; - if (nfs_async_handle_expired_key(task)) - return -EAGAIN; - if (task->tk_status >= 0) nfs_post_op_update_inode_force_wcc(inode, data->res.fattr); return 0; diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index c69e199b108..55e174f2d02 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -1381,6 +1381,7 @@ call_refreshresult(struct rpc_task *task) return; case -ETIMEDOUT: rpc_delay(task, 3*HZ); + case -EKEYEXPIRED: case -EAGAIN: status = -EACCES; if (!task->tk_cred_retry) -- cgit v1.2.3