Relevant BUGIDs:

Purpose of commit: cleanup

Commit summary:
---------------
Better check the input parameters of pam_start (by ldv)

1 files changed, 22 insertions, 13 deletions

diff --git a/libpam/pam_start.c b/libpam/pam_start.c
index bf7c9af9..63f58f5b 100644
--- a/libpam/pam_start.c
+++ b/libpam/pam_start.c
@@ -27,7 +27,19 @@ int pam_start (
     if (pamh == NULL) {
 	pam_syslog(NULL, LOG_CRIT,
 		   "pam_start: invalid argument: pamh == NULL");
-	return (PAM_BUF_ERR);
+	return (PAM_SYSTEM_ERR);
+    }
+
+    if (service_name == NULL) {
+	pam_syslog(NULL, LOG_CRIT,
+		   "pam_start: invalid argument: service == NULL");
+	return (PAM_SYSTEM_ERR);
+    }
+
+    if (pam_conversation == NULL) {
+	pam_syslog(NULL, LOG_CRIT,
+		   "pam_start: invalid argument: conv == NULL");
+	return (PAM_SYSTEM_ERR);
     }
 
     if ((*pamh = calloc(1, sizeof(**pamh))) == NULL) {
@@ -45,19 +57,17 @@ int pam_start (
 
     __PAM_TO_APP(*pamh);
 
-    if (service_name) {
+    if (((*pamh)->service_name = _pam_strdup(service_name)) == NULL) {
+	pam_syslog(*pamh, LOG_CRIT,
+		   "pam_start: _pam_strdup failed for service name");
+	_pam_drop(*pamh);
+	return (PAM_BUF_ERR);
+    } else {
 	char *tmp;
 
-	if (((*pamh)->service_name = _pam_strdup(service_name)) == NULL) {
-	    pam_syslog(*pamh, LOG_CRIT,
-	               "pam_start: _pam_strdup failed for service name");
-	    _pam_drop(*pamh);
-	    return (PAM_BUF_ERR);
-	}
 	for (tmp=(*pamh)->service_name; *tmp; ++tmp)
 	    *tmp = tolower(*tmp);                   /* require lower case */
-    } else
-       	(*pamh)->service_name = NULL;
+    }
 
     if (user) {
 	if (((*pamh)->user = _pam_strdup(user)) == NULL) {
@@ -79,9 +89,8 @@ int pam_start (
     (*pamh)->fail_delay.delay_fn_ptr = NULL;
     (*pamh)->former.choice = PAM_NOT_STACKED;
 
-    if (pam_conversation == NULL
-	|| ((*pamh)->pam_conversation = (struct pam_conv *)
-	    malloc(sizeof(struct pam_conv))) == NULL) {
+    if (((*pamh)->pam_conversation = (struct pam_conv *)
+	  malloc(sizeof(struct pam_conv))) == NULL) {
 	pam_syslog(*pamh, LOG_CRIT, "pam_start: malloc failed for pam_conv");
 	_pam_drop((*pamh)->service_name);
 	_pam_drop((*pamh)->user);