pam_smbpass: Wrap calls in talloc_stackframe() to avoid warnings about leaking memory

Any code in source3 is permitted to use talloc_tos() at any point, so we must protect all the library interfaces
against memory leaks this way.

Andrew Bartlett

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
(cherry picked from commit 8f3a516acb8c95cd6d88bf80abd495ac0cafaae3)

diff --git a/source3/pam_smbpass/pam_smb_acct.c b/source3/pam_smbpass/pam_smb_acct.c
index 60acd3c1ca5d8d310b28b4f5490acd3c4f13b364..bd4615f646e7f6517521acdaa781ef480c97db5f 100644 (file)
--- a/source3/pam_smbpass/pam_smb_acct.c
+++ b/source3/pam_smbpass/pam_smb_acct.c
@@ -55,6 +55,7 @@ int pam_sm_acct_mgmt( pam_handle_t *pamh, int flags,
        const char *name;
        struct samu *sampass = NULL;
        void (*oldsig_handler)(int);
+       TALLOC_CTX *frame = talloc_stackframe();
 
        /* Samba initialization. */
        load_case_tables_library();
@@ -68,6 +69,7 @@ int pam_sm_acct_mgmt( pam_handle_t *pamh, int flags,
                if (on( SMB_DEBUG, ctrl )) {
                        _log_err(pamh, LOG_DEBUG, "acct: could not identify user" );
                }
+               TALLOC_FREE(frame);
                return retval;
        }
        if (on( SMB_DEBUG, ctrl )) {
@@ -76,6 +78,7 @@ int pam_sm_acct_mgmt( pam_handle_t *pamh, int flags,
 
        if (geteuid() != 0) {
                _log_err(pamh, LOG_DEBUG, "Cannot access samba password database, not running as root.");
+               TALLOC_FREE(frame);
                return PAM_AUTHINFO_UNAVAIL;
        }
 
@@ -85,6 +88,7 @@ int pam_sm_acct_mgmt( pam_handle_t *pamh, int flags,
        if (!initialize_password_db(True, NULL)) {
          _log_err(pamh, LOG_ALERT, "Cannot access samba password database" );
                CatchSignal(SIGPIPE, oldsig_handler);
+               TALLOC_FREE(frame);
                return PAM_AUTHINFO_UNAVAIL;
        }
 
@@ -93,18 +97,21 @@ int pam_sm_acct_mgmt( pam_handle_t *pamh, int flags,
        if (!(sampass = samu_new( NULL ))) {
                CatchSignal(SIGPIPE, oldsig_handler);
                /* malloc fail. */
+               TALLOC_FREE(frame);
                return nt_status_to_pam(NT_STATUS_NO_MEMORY);
        }
 
        if (!pdb_getsampwnam(sampass, name )) {
                _log_err(pamh, LOG_DEBUG, "acct: could not identify user");
                CatchSignal(SIGPIPE, oldsig_handler);
+               TALLOC_FREE(frame);
                return PAM_USER_UNKNOWN;
        }
 
        /* check for lookup failure */
        if (!strlen(pdb_get_username(sampass)) ) {
                CatchSignal(SIGPIPE, oldsig_handler);
+               TALLOC_FREE(frame);
                return PAM_USER_UNKNOWN;
        }
 
@@ -118,12 +125,14 @@ int pam_sm_acct_mgmt( pam_handle_t *pamh, int flags,
                        "please see your system administrator." );
 
                CatchSignal(SIGPIPE, oldsig_handler);
+               TALLOC_FREE(frame);
                return PAM_ACCT_EXPIRED;
        }
 
        /* TODO: support for expired passwords. */
 
        CatchSignal(SIGPIPE, oldsig_handler);
+       TALLOC_FREE(frame);
        return PAM_SUCCESS;
 }
 

diff --git a/source3/pam_smbpass/pam_smb_auth.c b/source3/pam_smbpass/pam_smb_auth.c
index 4270bcce58787dbb51a2a8c375471e1ee559facd..ac5ef3f21c5156a0f028eb73f482e4668c72cb65 100644 (file)
--- a/source3/pam_smbpass/pam_smb_auth.c
+++ b/source3/pam_smbpass/pam_smb_auth.c
@@ -50,6 +50,7 @@ do {                                                          \
                pam_set_data( pamh, "smb_setcred_return"        \
                              , (void *) ret_data, NULL );      \
        }                                                       \
+       TALLOC_FREE(frame);                                     \
        return retval;                                          \
 } while (0)
 
@@ -75,6 +76,7 @@ int pam_sm_authenticate(pam_handle_t *pamh, int flags,
        const char *name;
        void (*oldsig_handler)(int) = NULL;
        bool found;
+       TALLOC_CTX *frame = talloc_stackframe();
 
        /* Points to memory managed by the PAM library. Do not free. */
        char *p = NULL;
@@ -195,6 +197,7 @@ static int _smb_add_user(pam_handle_t *pamh, unsigned int ctrl,
        char *msg_str = NULL;
        const char *pass = NULL;
        int retval;
+       TALLOC_CTX *frame = talloc_stackframe();
 
        /* Get the authtok; if we don't have one, silently fail. */
        retval = _pam_get_item( pamh, PAM_AUTHTOK, &pass );
@@ -202,8 +205,10 @@ static int _smb_add_user(pam_handle_t *pamh, unsigned int ctrl,
        if (retval != PAM_SUCCESS) {
                _log_err(pamh, LOG_ALERT
                        , "pam_get_item returned error to pam_sm_authenticate" );
+               TALLOC_FREE(frame);
                return PAM_AUTHTOK_RECOVER_ERR;
        } else if (pass == NULL) {
+               TALLOC_FREE(frame);
                return PAM_AUTHTOK_RECOVER_ERR;
        }
 
@@ -220,6 +225,7 @@ static int _smb_add_user(pam_handle_t *pamh, unsigned int ctrl,
 
                SAFE_FREE(err_str);
                SAFE_FREE(msg_str);
+               TALLOC_FREE(frame);
                return PAM_IGNORE;
        } else {
                /* mimick 'update encrypted' as long as the 'no pw req' flag is not set */
@@ -237,6 +243,7 @@ static int _smb_add_user(pam_handle_t *pamh, unsigned int ctrl,
        SAFE_FREE(err_str);
        SAFE_FREE(msg_str);
        pass = NULL;
+       TALLOC_FREE(frame);
        return PAM_IGNORE;
 }
 

diff --git a/source3/pam_smbpass/pam_smb_passwd.c b/source3/pam_smbpass/pam_smb_passwd.c
index ce0b1187d806d8bb89c8ace91a4ebd78ae09f762..dedfda03ffb3575dd98b4f840edac0fddd19efc2 100644 (file)
--- a/source3/pam_smbpass/pam_smb_passwd.c
+++ b/source3/pam_smbpass/pam_smb_passwd.c
@@ -103,6 +103,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
     const char *user;
     char *pass_old;
     char *pass_new;
+    TALLOC_CTX *frame = talloc_stackframe();
 
     /* Samba initialization. */
     load_case_tables_library();
@@ -119,6 +120,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
         if (on( SMB_DEBUG, ctrl )) {
             _log_err(pamh, LOG_DEBUG, "password: could not identify user");
         }
+       TALLOC_FREE(frame);
         return retval;
     }
     if (on( SMB_DEBUG, ctrl )) {
@@ -127,6 +129,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
 
     if (geteuid() != 0) {
        _log_err(pamh, LOG_DEBUG, "Cannot access samba password database, not running as root.");
+       TALLOC_FREE(frame);
        return PAM_AUTHINFO_UNAVAIL;
     }
 
@@ -137,19 +140,22 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
     if (!initialize_password_db(False, NULL)) {
       _log_err(pamh, LOG_ALERT, "Cannot access samba password database" );
         CatchSignal(SIGPIPE, oldsig_handler);
+       TALLOC_FREE(frame);
         return PAM_AUTHINFO_UNAVAIL;
     }
 
     /* obtain user record */
     if ( !(sampass = samu_new( NULL )) ) {
         CatchSignal(SIGPIPE, oldsig_handler);
+       TALLOC_FREE(frame);
         return nt_status_to_pam(NT_STATUS_NO_MEMORY);
     }
 
     if (!pdb_getsampwnam(sampass,user)) {
         _log_err(pamh, LOG_ALERT, "Failed to find entry for user %s.", user);
         CatchSignal(SIGPIPE, oldsig_handler);
-        return PAM_USER_UNKNOWN;
+       TALLOC_FREE(frame);
+       return PAM_USER_UNKNOWN;
     }
     if (on( SMB_DEBUG, ctrl )) {
         _log_err(pamh, LOG_DEBUG, "Located account for %s", user);
@@ -167,6 +173,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
 
             TALLOC_FREE(sampass);
             CatchSignal(SIGPIPE, oldsig_handler);
+           TALLOC_FREE(frame);
             return PAM_SUCCESS;
         }
 
@@ -179,6 +186,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
                        _log_err(pamh, LOG_CRIT, "password: out of memory");
                        TALLOC_FREE(sampass);
                        CatchSignal(SIGPIPE, oldsig_handler);
+                       TALLOC_FREE(frame);
                        return PAM_BUF_ERR;
                }
 
@@ -192,6 +200,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
                          "password - (old) token not obtained");
                 TALLOC_FREE(sampass);
                 CatchSignal(SIGPIPE, oldsig_handler);
+               TALLOC_FREE(frame);
                 return retval;
             }
 
@@ -207,6 +216,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
         pass_old = NULL;
         TALLOC_FREE(sampass);
         CatchSignal(SIGPIPE, oldsig_handler);
+       TALLOC_FREE(frame);
         return retval;
 
     } else if (flags & PAM_UPDATE_AUTHTOK) {
@@ -237,6 +247,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
             _log_err(pamh, LOG_NOTICE, "password: user not authenticated");
             TALLOC_FREE(sampass);
             CatchSignal(SIGPIPE, oldsig_handler);
+           TALLOC_FREE(frame);
             return retval;
         }
 
@@ -265,6 +276,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
             pass_old = NULL;                               /* tidy up */
             TALLOC_FREE(sampass);
             CatchSignal(SIGPIPE, oldsig_handler);
+           TALLOC_FREE(frame);
             return retval;
         }
 
@@ -285,6 +297,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
             pass_new = pass_old = NULL;               /* tidy up */
             TALLOC_FREE(sampass);
             CatchSignal(SIGPIPE, oldsig_handler);
+           TALLOC_FREE(frame);
             return retval;
         }
 
@@ -334,6 +347,7 @@ int pam_sm_chauthtok(pam_handle_t *pamh, int flags,
 
     TALLOC_FREE(sampass);
     CatchSignal(SIGPIPE, oldsig_handler);
+    TALLOC_FREE(frame);
     return retval;
 }