3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Adamson <andros@xxxxxxxxxx> commit eb96d5c97b0825d542e9c4ba5e0a22b519355166 upstream. 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 <andros@xxxxxxxxxx> Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> [bwh: Backported to 3.2: - Adjust context - Drop change to nfs4_handle_reclaim_lease_error()] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/nfs/nfs3proc.c | 6 +++--- fs/nfs/nfs4filelayout.c | 1 - fs/nfs/nfs4proc.c | 18 ------------------ fs/nfs/nfs4state.c | 21 --------------------- fs/nfs/proc.c | 43 ------------------------------------------- net/sunrpc/clnt.c | 1 + 6 files changed, 4 insertions(+), 86 deletions(-) --- 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, 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); --- a/fs/nfs/nfs4filelayout.c +++ b/fs/nfs/nfs4filelayout.c @@ -122,7 +122,6 @@ static int filelayout_async_handle_error break; case -NFS4ERR_DELAY: case -NFS4ERR_GRACE: - case -EKEYEXPIRED: rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX); break; case -NFS4ERR_RETRY_UNCACHED_REP: --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -319,7 +319,6 @@ static int nfs4_handle_exception(struct } case -NFS4ERR_GRACE: case -NFS4ERR_DELAY: - case -EKEYEXPIRED: ret = nfs4_delay(server->client, &exception->timeout); if (ret != 0) break; @@ -1352,13 +1351,6 @@ int nfs4_open_delegation_recall(struct n 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; @@ -3924,7 +3916,6 @@ nfs4_async_handle_error(struct rpc_task 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; @@ -4871,15 +4862,6 @@ int nfs4_lock_delegation_recall(struct n 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); */ --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1298,14 +1298,6 @@ 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: @@ -1458,14 +1450,6 @@ static void nfs4_state_start_reclaim_nog 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) { @@ -1497,10 +1481,6 @@ static int nfs4_recovery_handle_error(st set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state); /* Zero session reset errors */ break; - case -EKEYEXPIRED: - /* Nothing we can do */ - nfs4_warn_keyexpired(clp->cl_hostname); - break; default: return error; } @@ -1745,7 +1725,6 @@ static void nfs4_set_lease_expired(struc break; case -EKEYEXPIRED: - nfs4_warn_keyexpired(clp->cl_hostname); case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery * in nfs4_exchange_id */ default: --- a/fs/nfs/proc.c +++ b/fs/nfs/proc.c @@ -47,39 +47,6 @@ #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. */ static int @@ -365,8 +332,6 @@ static void nfs_proc_unlink_rpc_prepare( 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; } @@ -386,8 +351,6 @@ 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; @@ -641,9 +604,6 @@ nfs_proc_pathconf(struct nfs_server *ser static int nfs_read_done(struct rpc_task *task, struct nfs_read_data *data) { - if (nfs_async_handle_expired_key(task)) - return -EAGAIN; - nfs_invalidate_atime(data->inode); if (task->tk_status >= 0) { nfs_refresh_inode(data->inode, data->res.fattr); @@ -668,9 +628,6 @@ static void nfs_proc_read_rpc_prepare(st static int nfs_write_done(struct rpc_task *task, struct nfs_write_data *data) { - if (nfs_async_handle_expired_key(task)) - return -EAGAIN; - if (task->tk_status >= 0) nfs_post_op_update_inode_force_wcc(data->inode, data->res.fattr); return 0; --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -1336,6 +1336,7 @@ 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) -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html