ceph: ensure auth ops are defined before use

In the create_authorizer method for both the mds and osd clients,
the auth_client->ops pointer is blindly dereferenced.  There is no
obvious guarantee that this pointer has been assigned.  And
furthermore, even if the ops pointer is non-null there is definitely
no guarantee that the create_authorizer or destroy_authorizer
methods are defined.

Add checks in both routines to make sure they are defined (non-null)
before use.  Add similar checks in a few other spots in these files
while we're at it.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index b71ffd2c80942f71bb338df0580129d4c7ea8a39..462281742aefd3eaf3ddb1698016a6081e4faf67 100644 (file)
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -3406,16 +3406,14 @@ static int get_authorizer(struct ceph_connection *con,
        int ret = 0;
 
        if (force_new && auth->authorizer) {
-               ac->ops->destroy_authorizer(ac, auth->authorizer);
+               if (ac->ops && ac->ops->destroy_authorizer)
+                       ac->ops->destroy_authorizer(ac, auth->authorizer);
                auth->authorizer = NULL;
        }
-       if (auth->authorizer == NULL) {
-               if (ac->ops->create_authorizer) {
-                       ret = ac->ops->create_authorizer(ac,
-                                               CEPH_ENTITY_TYPE_MDS, auth);
-                       if (ret)
-                               return ret;
-               }
+       if (!auth->authorizer && ac->ops && ac->ops->create_authorizer) {
+               ret = ac->ops->create_authorizer(ac, CEPH_ENTITY_TYPE_MDS, auth);
+               if (ret)
+                       return ret;
        }
 
        *proto = ac->protocol;

diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 2da4b9e97dc165b03deb7be1928e2df800157290..f640bdf027e79f868054f5ce534810aba682a2cb 100644 (file)
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -664,10 +664,10 @@ static void put_osd(struct ceph_osd *osd)
 {
        dout("put_osd %p %d -> %d\n", osd, atomic_read(&osd->o_ref),
             atomic_read(&osd->o_ref) - 1);
-       if (atomic_dec_and_test(&osd->o_ref)) {
+       if (atomic_dec_and_test(&osd->o_ref) && osd->o_auth.authorizer) {
                struct ceph_auth_client *ac = osd->o_osdc->client->monc.auth;
 
-               if (osd->o_auth.authorizer)
+               if (ac->ops && ac->ops->destroy_authorizer)
                        ac->ops->destroy_authorizer(ac, osd->o_auth.authorizer);
                kfree(osd);
        }
@@ -2119,10 +2119,11 @@ static int get_authorizer(struct ceph_connection *con,
        int ret = 0;
 
        if (force_new && auth->authorizer) {
-               ac->ops->destroy_authorizer(ac, auth->authorizer);
+               if (ac->ops && ac->ops->destroy_authorizer)
+                       ac->ops->destroy_authorizer(ac, auth->authorizer);
                auth->authorizer = NULL;
        }
-       if (auth->authorizer == NULL) {
+       if (!auth->authorizer && ac->ops && ac->ops->create_authorizer) {
                ret = ac->ops->create_authorizer(ac, CEPH_ENTITY_TYPE_OSD, auth);
                if (ret)
                        return ret;
@@ -2144,6 +2145,10 @@ static int verify_authorizer_reply(struct ceph_connection *con, int len)
        struct ceph_osd_client *osdc = o->o_osdc;
        struct ceph_auth_client *ac = osdc->client->monc.auth;
 
+       /*
+        * XXX If ac->ops or ac->ops->verify_authorizer_reply is null,
+        * XXX which do we do:  succeed or fail?
+        */
        return ac->ops->verify_authorizer_reply(ac, o->o_auth.authorizer, len);
 }
 
@@ -2153,7 +2158,7 @@ static int invalidate_authorizer(struct ceph_connection *con)
        struct ceph_osd_client *osdc = o->o_osdc;
        struct ceph_auth_client *ac = osdc->client->monc.auth;
 
-       if (ac->ops->invalidate_authorizer)
+       if (ac->ops && ac->ops->invalidate_authorizer)
                ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_OSD);
 
        return ceph_monc_validate_auth(&osdc->client->monc);