LU-17212 gss: survive improper obd or imp at ctx init

GSS context init requests can happen even after a client has been
unmounted, because they are coming from userspace (request-key,
lgss_keyring).
In this case they must be ignored, and code must be robust to survive
improper, already or partially shutdown obd device or import.

Test-Parameters: kerberos=true testlist=sanity-krb5
Signed-off-by: Sebastien Buisson <sbuisson@ddn.com>
Change-Id: I541727165eadf1fcb7715e416da85d100976cf2f
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/52755
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Aurelien Degremont <adegremont@nvidia.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lustre/ptlrpc/gss/gss_cli_upcall.c b/lustre/ptlrpc/gss/gss_cli_upcall.c
index 3e901e5..073fa12 100644 (file)
--- a/lustre/ptlrpc/gss/gss_cli_upcall.c
+++ b/lustre/ptlrpc/gss/gss_cli_upcall.c
@@ -222,7 +222,7 @@ int ctx_init_parse_reply(struct lustre_msg *msg, int swabbed,
 
 int gss_do_ctx_init_rpc(char __user *buffer, unsigned long count)
 {
-       struct obd_import *imp, *imp0;
+       struct obd_import *imp = NULL, *imp0;
        struct ptlrpc_request *req;
        struct lgssd_ioctl_param param;
        struct obd_device *obd;
@@ -255,20 +255,30 @@ int gss_do_ctx_init_rpc(char __user *buffer, unsigned long count)
 
        obd = class_name2obd(obdname);
        if (!obd) {
-               CERROR("no such obd %s\n", obdname);
-               RETURN(-EINVAL);
+               rc = -EINVAL;
+               CERROR("%s: no such obd: rc = %d\n", obdname, rc);
+               RETURN(rc);
        }
 
        if (unlikely(!obd->obd_set_up)) {
-               CERROR("obd %s not setup\n", obdname);
-               RETURN(-EINVAL);
+               rc = -EINVAL;
+               CERROR("%s: obd not setup: rc = %d\n", obdname, rc);
+               RETURN(rc);
        }
 
        spin_lock(&obd->obd_dev_lock);
        if (obd->obd_stopping) {
-               CERROR("obd %s has stopped\n", obdname);
+               rc = -EINVAL;
+               CERROR("%s: obd has stopped: rc = %d\n", obdname, rc);
                spin_unlock(&obd->obd_dev_lock);
-               RETURN(-EINVAL);
+               RETURN(rc);
+       }
+
+       if (!obd->obd_type || obd->obd_magic != OBD_DEVICE_MAGIC) {
+               rc = -EINVAL;
+               CERROR("%s: obd not valid: rc = %d\n", obdname, rc);
+               spin_unlock(&obd->obd_dev_lock);
+               RETURN(rc);
        }
 
        if (strcmp(obd->obd_type->typ_name, LUSTRE_MDC_NAME) &&
@@ -276,36 +286,47 @@ int gss_do_ctx_init_rpc(char __user *buffer, unsigned long count)
            strcmp(obd->obd_type->typ_name, LUSTRE_MGC_NAME) &&
            strcmp(obd->obd_type->typ_name, LUSTRE_LWP_NAME) &&
            strcmp(obd->obd_type->typ_name, LUSTRE_OSP_NAME)) {
-               CERROR("obd %s is not a client device\n", obdname);
+               rc = -EINVAL;
+               CERROR("%s: obd is not a client device: rc = %d\n",
+                      obdname, rc);
                spin_unlock(&obd->obd_dev_lock);
-               RETURN(-EINVAL);
+               RETURN(rc);
        }
        spin_unlock(&obd->obd_dev_lock);
 
-       with_imp_locked(obd, imp0, rc)
-               imp = class_import_get(imp0);
+       with_imp_locked(obd, imp0, rc) {
+               if (!imp0->imp_obd || !imp0->imp_sec)
+                       rc = -ENODEV;
+               else
+                       imp = class_import_get(imp0);
+       }
        if (rc) {
-               CERROR("obd %s: import has gone\n", obd->obd_name);
-               RETURN(-EINVAL);
+               rc = -EINVAL;
+               CERROR("%s: import has gone: rc = %d\n", obd->obd_name, rc);
+               RETURN(rc);
        }
 
        if (imp->imp_deactive) {
-               CERROR("import has been deactivated\n");
+               rc = -EINVAL;
+               CERROR("%s: import has been deactivated: rc = %d\n",
+                      obd->obd_name, rc);
                class_import_put(imp);
-               RETURN(-EINVAL);
+               RETURN(rc);
        }
 
        req = ptlrpc_request_alloc_pack(imp, &RQF_SEC_CTX, LUSTRE_OBD_VERSION,
                                        SEC_CTX_INIT);
-       if (req == NULL) {
+       if (!req || !req->rq_cli_ctx || !req->rq_cli_ctx->cc_sec) {
                param.status = -ENOMEM;
                goto out_copy;
        }
 
        if (req->rq_cli_ctx->cc_sec->ps_id != param.secid) {
-               CWARN("original secid %d, now has changed to %d, cancel this negotiation\n",
-                     param.secid, req->rq_cli_ctx->cc_sec->ps_id);
-               param.status = -EINVAL;
+               rc = -EINVAL;
+               CWARN("%s: original secid %d, now has changed to %d, cancel this negotiation: rc = %d\n",
+                     obd->obd_name, param.secid,
+                     req->rq_cli_ctx->cc_sec->ps_id, rc);
+               param.status = rc;
                goto out_copy;
        }