r22020: Make it more clear that both the vuser struct and it's contents are

talloc_free()'ed at the end of a session.

Rework the passwd cache code to use talloc_unlink and
talloc_reference, to more carefully manage the cache.

Andrew Bartlett
(This used to be commit e3e0ec25e67308de314aa61852905ee42aa2c8fe)

diff --git a/source3/auth/auth_sam.c b/source3/auth/auth_sam.c
index 847315ef888dd856629c4a1db7be7d1a4c55c96f..31178a761ce8b13131838b4195aa67eefd619c5d 100644 (file)
--- a/source3/auth/auth_sam.c
+++ b/source3/auth/auth_sam.c
@@ -266,7 +266,7 @@ static NTSTATUS check_sam_security(const struct auth_context *auth_context,
        /* Can't use the talloc version here, because the returned struct gets
           kept on the server_info */
 
-       if ( !(sampass = samu_new( NULL )) ) {
+       if ( !(sampass = samu_new( mem_ctx )) ) {
                return NT_STATUS_NO_MEMORY;
        }
 

diff --git a/source3/auth/auth_util.c b/source3/auth/auth_util.c
index 82567473b5cdad87cf31f84571f378899a9e5edf..5c3bf7acceb7e966ce772f726f6278c87067109b 100644 (file)
--- a/source3/auth/auth_util.c
+++ b/source3/auth/auth_util.c
@@ -561,19 +561,23 @@ NTSTATUS make_server_info_sam(auth_serversupplied_info **server_info,
        DOM_SID unix_group_sid;
        
 
-       if ( !(pwd = getpwnam_alloc(NULL, pdb_get_username(sampass))) ) {
-               DEBUG(1, ("User %s in passdb, but getpwnam() fails!\n",
-                         pdb_get_username(sampass)));
-               return NT_STATUS_NO_SUCH_USER;
-       }
-
        if ( !(result = make_server_info(NULL)) ) {
                TALLOC_FREE(pwd);
                return NT_STATUS_NO_MEMORY;
        }
 
+       if ( !(pwd = getpwnam_alloc(result, pdb_get_username(sampass))) ) {
+               DEBUG(1, ("User %s in passdb, but getpwnam() fails!\n",
+                         pdb_get_username(sampass)));
+               return NT_STATUS_NO_SUCH_USER;
+       }
+
        result->sam_account = sampass;
-       result->unix_name = talloc_strdup(result, pwd->pw_name);
+       /* Ensure thaat the sampass will be freed with the result */
+       talloc_steal(result, sampass);
+       result->unix_name = pwd->pw_name;
+       /* Ensure that we keep pwd->pw_name, because we will free pwd below */
+       talloc_steal(result, pwd->pw_name);
        result->gid = pwd->pw_gid;
        result->uid = pwd->pw_uid;
        

diff --git a/source3/include/smb.h b/source3/include/smb.h
index 2eed76eb8098777f52a45e526a4793f5dd05e773..722c34d9d3f99488cea62bc0e8d57581559aeaae 100644 (file)
--- a/source3/include/smb.h
+++ b/source3/include/smb.h
@@ -1737,9 +1737,9 @@ typedef struct user_struct {
        gid_t gid; /* gid of a validated user */
 
        userdom_struct user;
-       char *homedir;
-       char *unix_homedir;
-       char *logon_script;
+       const char *homedir;
+       const char *unix_homedir;
+       const char *logon_script;
        
        BOOL guest;
 

diff --git a/source3/lib/util_pw.c b/source3/lib/util_pw.c
index dc184233a6db5d7566ad785c085be8aa8c03ac1a..8b3c78a3f97d8aef413f2f7782bb65f1254b4fe9 100644 (file)
--- a/source3/lib/util_pw.c
+++ b/source3/lib/util_pw.c
@@ -98,15 +98,15 @@ struct passwd *getpwnam_alloc(TALLOC_CTX *mem_ctx, const char *name)
                i = rand() % PWNAMCACHE_SIZE;
 
        if (pwnam_cache[i] != NULL) {
-               TALLOC_FREE(pwnam_cache[i]);
+               /* Remove this old cache entry, from the cache.  We
+                * use talloc_unlink here because we want to be very
+                * clear which referece we are removing */
+               talloc_unlink(pwnam_cache, pwnam_cache[i]);
        }
 
        pwnam_cache[i] = tcopy_passwd(pwnam_cache, temp);
-       if (pwnam_cache[i]!= NULL && mem_ctx != NULL) {
-               return (struct passwd *)talloc_reference(mem_ctx, pwnam_cache[i]);
-       }
-
-       return tcopy_passwd(NULL, pwnam_cache[i]);
+       /* while keeping this in the cache, reference a copy for the caller */
+       return (struct passwd *)talloc_reference(mem_ctx, pwnam_cache[i]);
 }
 
 struct passwd *getpwuid_alloc(TALLOC_CTX *mem_ctx, uid_t uid) 

diff --git a/source3/smbd/password.c b/source3/smbd/password.c
index bf4e9258ff266307887b00223fb29c012e70eba9..b7945bd7eacad8aba6f232b4532a61bb50de9973 100644 (file)
--- a/source3/smbd/password.c
+++ b/source3/smbd/password.c
@@ -92,14 +92,7 @@ void invalidate_vuid(uint16 vuid)
        if (vuser == NULL)
                return;
        
-       SAFE_FREE(vuser->homedir);
-       SAFE_FREE(vuser->unix_homedir);
-       SAFE_FREE(vuser->logon_script);
-       
        session_yield(vuser);
-       SAFE_FREE(vuser->session_keystr);
-
-       TALLOC_FREE(vuser->server_info);
 
        data_blob_free(&vuser->session_key);
 
@@ -109,10 +102,7 @@ void invalidate_vuid(uint16 vuid)
           from the vuid 'owner' of connections */
        conn_clear_vuid_cache(vuid);
 
-       SAFE_FREE(vuser->groups);
-       TALLOC_FREE(vuser->nt_user_token);
-
-       SAFE_FREE(vuser);
+       TALLOC_FREE(vuser);
        num_validated_vuids--;
 }
 
@@ -153,7 +143,7 @@ int register_vuid(auth_serversupplied_info *server_info,
                  DATA_BLOB session_key, DATA_BLOB response_blob,
                  const char *smb_name)
 {
-       user_struct *vuser = NULL;
+       user_struct *vuser;
 
        /* Paranoia check. */
        if(lp_security() == SEC_SHARE) {
@@ -166,14 +156,12 @@ int register_vuid(auth_serversupplied_info *server_info,
                return UID_FIELD_INVALID;
        }
 
-       if((vuser = SMB_MALLOC_P(user_struct)) == NULL) {
-               DEBUG(0,("Failed to malloc users struct!\n"));
+       if((vuser = talloc_zero(NULL, user_struct)) == NULL) {
+               DEBUG(0,("Failed to talloc users struct!\n"));
                data_blob_free(&session_key);
                return UID_FIELD_INVALID;
        }
 
-       ZERO_STRUCTP(vuser);
-
        /* Allocate a free vuid. Yes this is a linear search... :-) */
        while( get_valid_user_struct(next_vuid) != NULL ) {
                next_vuid++;
@@ -203,6 +191,11 @@ int register_vuid(auth_serversupplied_info *server_info,
                return vuser->vuid;
        }
 
+       /* use this to keep tabs on all our info from the authentication */
+       vuser->server_info = server_info;
+       /* Ensure that the server_info will dissapear with the vuser it is now attached to */
+       talloc_steal(vuser, vuser->server_info);
+
        /* the next functions should be done by a SID mapping system (SMS) as
         * the new real sam db won't have reference to unix uids or gids
         */
@@ -212,14 +205,13 @@ int register_vuid(auth_serversupplied_info *server_info,
        
        vuser->n_groups = server_info->n_groups;
        if (vuser->n_groups) {
-               if (!(vuser->groups = (gid_t *)memdup(server_info->groups,
-                                                     sizeof(gid_t) *
-                                                     vuser->n_groups))) {
-                       DEBUG(0,("register_vuid: failed to memdup "
+               if (!(vuser->groups = (gid_t *)talloc_memdup(vuser, server_info->groups,
+                                                            sizeof(gid_t) *
+                                                            vuser->n_groups))) {
+                       DEBUG(0,("register_vuid: failed to talloc_memdup "
                                 "vuser->groups\n"));
                        data_blob_free(&session_key);
-                       free(vuser);
-                       TALLOC_FREE(server_info);
+                       TALLOC_FREE(vuser);
                        return UID_FIELD_INVALID;
                }
        }
@@ -247,24 +239,26 @@ int register_vuid(auth_serversupplied_info *server_info,
                        const char *unix_homedir =
                                pdb_get_unix_homedir(server_info->sam_account);
                        if (unix_homedir) {
-                               vuser->unix_homedir =
-                                       smb_xstrdup(unix_homedir);
+                               vuser->unix_homedir = unix_homedir;
                        }
                } else {
                        struct passwd *passwd =
-                               getpwnam_alloc(NULL, vuser->user.unix_name);
+                               getpwnam_alloc(vuser, vuser->user.unix_name);
                        if (passwd) {
-                               vuser->unix_homedir =
-                                       smb_xstrdup(passwd->pw_dir);
+                               vuser->unix_homedir = passwd->pw_dir;
+                               /* Ensure that the unix_homedir now
+                                * belongs to vuser, so it goes away
+                                * with it, not with passwd below: */
+                               talloc_steal(vuser, vuser->unix_homedir);
                                TALLOC_FREE(passwd);
                        }
                }
                
                if (homedir) {
-                       vuser->homedir = smb_xstrdup(homedir);
+                       vuser->homedir = homedir;
                }
                if (logon_script) {
-                       vuser->logon_script = smb_xstrdup(logon_script);
+                       vuser->logon_script = logon_script;
                }
        }
 
@@ -280,23 +274,15 @@ int register_vuid(auth_serversupplied_info *server_info,
                  vuser->user.full_name));      
 
        if (server_info->ptok) {
-               vuser->nt_user_token = dup_nt_token(NULL, server_info->ptok);
+               vuser->nt_user_token = dup_nt_token(vuser, server_info->ptok);
        } else {
                DEBUG(1, ("server_info does not contain a user_token - "
                          "cannot continue\n"));
-               TALLOC_FREE(server_info);
+               TALLOC_FREE(vuser);
                data_blob_free(&session_key);
-               SAFE_FREE(vuser->homedir);
-               SAFE_FREE(vuser->unix_homedir);
-               SAFE_FREE(vuser->logon_script);
-
-               SAFE_FREE(vuser);
                return UID_FIELD_INVALID;
        }
 
-       /* use this to keep tabs on all our info from the authentication */
-       vuser->server_info = server_info;
-
        DEBUG(3,("UNIX uid %d is UNIX user %s, and will be vuid %u\n",
                 (int)vuser->uid,vuser->user.unix_name, vuser->vuid));
 

diff --git a/source3/smbd/session.c b/source3/smbd/session.c
index a3334a353e3bb735b0ef6def50c2e606411c5d44..05b1026f41fc1fdbe1923f6add215632a924a4b3 100644 (file)
--- a/source3/smbd/session.c
+++ b/source3/smbd/session.c
@@ -153,9 +153,9 @@ BOOL session_claim(user_struct *vuser)
                               sessionid.id_str, sessionid.id_num);
        }
 
-       vuser->session_keystr = SMB_STRDUP(keystr);
+       vuser->session_keystr = talloc_strdup(vuser, keystr);
        if (!vuser->session_keystr) {
-               DEBUG(0, ("session_claim:  strdup() failed for session_keystr\n"));
+               DEBUG(0, ("session_claim:  talloc_strdup() failed for session_keystr\n"));
                return False;
        }
        return True;