Merge pull request #11526 from ukernel/wip-17591

client: get caller's uid/gid on every libcephfs operation

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Greg Farnum <gfarnum@redhat.com>

src/client/Client.h

@@ -292,14 +292,14 @@ class Client : public Dispatcher, public md_config_obs_t {
   void tick();
 
   UserPerm pick_my_perms() {
-    uid_t uid = user_id >= 0 ? user_id : ::geteuid();
-    gid_t gid = group_id >= 0 ? group_id : ::getegid();
+    uid_t uid = user_id >= 0 ? user_id : -1;
+    gid_t gid = group_id >= 0 ? group_id : -1;
     return UserPerm(uid, gid);
   }
 
   static UserPerm pick_my_perms(CephContext *c) {
-    uid_t uid = c->_conf->client_mount_uid >= 0 ? c->_conf->client_mount_uid : ::geteuid();
-    gid_t gid = c->_conf->client_mount_gid >= 0 ? c->_conf->client_mount_gid : ::getegid();
+    uid_t uid = c->_conf->client_mount_uid >= 0 ? c->_conf->client_mount_uid : -1;
+    gid_t gid = c->_conf->client_mount_gid >= 0 ? c->_conf->client_mount_gid : -1;
     return UserPerm(uid, gid);
   }
 protected:

src/client/UserPerm.h

@@ -65,8 +65,8 @@ struct UserPerm
     return *this;
   }
 
-  uid_t uid() const { return m_uid; }
-  gid_t gid() const { return m_gid; }
+  uid_t uid() const { return m_uid != (uid_t)-1 ? m_uid : ::geteuid(); }
+  gid_t gid() const { return m_gid != (gid_t)-1 ? m_gid : ::getegid(); }
   bool gid_in_groups(gid_t gid) const {
     if (gid == m_gid) return true;
     for (int i = 0; i < gid_count; ++i) {