From: shumikhinaka <shumikhinaka@sgu.ru>
Date: Tue, 30 Jun 2026 19:51:34 +0000 (+0400)
Subject: pam_winbind: fix partial configuration argument matching
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5bc9de27802120bfd405bc66d496dbd7b3ab4d66;p=thirdparty%2Fsamba.git

pam_winbind: fix partial configuration argument matching

get_config_item_int and get_conf_item_string function used strncmp
to check command line arguments, but didn't verify the trailing character.
This allowed partial prefix matches
(e.g., matching "itemXYZ=value" when looking for "item").

Refactored lookup-logic to ensure correct parsing.

Pair-Programmed-With: Dmitry Mikhalchenko <tascad@altlinux.org>
Signed-off-by: Shumikhina Ksenia <shumikhinaka@sgu.ru>
Reviewed-by: Anoop C S <anoopcs@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>

Autobuild-User(master): Volker Lendecke <vl@samba.org>
Autobuild-Date(master): Wed Jul  1 09:30:23 UTC 2026 on atb-devel-224
---

diff --git a/nsswitch/pam_winbind.c b/nsswitch/pam_winbind.c
index cb9edb4bc7b..9f305144f1b 100644
--- a/nsswitch/pam_winbind.c
+++ b/nsswitch/pam_winbind.c
@@ -2325,21 +2325,29 @@ static const char *get_conf_item_string(struct pwb_context *ctx,
 	}
 
 	/* let the pam opt take precedence over the pam_winbind.conf option */
-	for (i=0; i<ctx->argc; i++) {
+	for (i = 0; i < ctx->argc; i++) {
+		const char *p = strchr(ctx->argv[i], '=');
+		if (p != NULL) {
+			size_t len = p - ctx->argv[i];
+			char name[len + 1];
 
-		if ((strncmp(ctx->argv[i], item, strlen(item)) == 0)) {
-			const char *p;
+			memcpy(name, ctx->argv[i], len);
+			name[len] = 0;
 
-			if ((p = strchr(ctx->argv[i], '=')) == NULL) {
-				_pam_log(ctx, LOG_INFO,
-					 "no \"=\" delimiter for \"%s\" found\n",
-					 item);
-				goto out;
+			if (strcmp(name, item) != 0) {
+				continue;
 			}
 			_pam_log_debug(ctx, LOG_INFO,
-				       "PAM config: %s '%s'\n", item, p+1);
+				       "PAM config: %s '%s'\n",
+				       item, p + 1);
 			return p + 1;
 		}
+		if (strcmp(ctx->argv[i], item) == 0) {
+			_pam_log(ctx, LOG_INFO,
+				 "no \"=\" delimiter for \"%s\" found\n",
+				 item);
+			goto out;
+		}
 	}
 
 	if (ctx->dict) {
@@ -2364,49 +2372,14 @@ static int get_config_item_int(struct pwb_context *ctx,
 			       const char *item,
 			       int config_flag)
 {
-	int i, parm_opt = -1;
-
-	if (!(ctx->ctrl & config_flag)) {
-		goto out;
-	}
-
-	/* let the pam opt take precedence over the pam_winbind.conf option */
-	for (i = 0; i < ctx->argc; i++) {
+	const char *value;
 
-		if ((strncmp(ctx->argv[i], item, strlen(item)) == 0)) {
-			const char *p;
-
-			if ((p = strchr(ctx->argv[i], '=')) == NULL) {
-				_pam_log(ctx, LOG_INFO,
-					 "no \"=\" delimiter for \"%s\" found\n",
-					 item);
-				goto out;
-			}
-			parm_opt = atoi(p + 1);
-			_pam_log_debug(ctx, LOG_INFO,
-				       "PAM config: %s '%d'\n",
-				       item, parm_opt);
-			return parm_opt;
-		}
+	value = get_conf_item_string(ctx, item, config_flag);
+	if (value == NULL) {
+		return -1;
 	}
 
-	if (ctx->dict) {
-		char *key = NULL;
-
-		key = talloc_asprintf(ctx, "global:%s", item);
-		if (!key) {
-			goto out;
-		}
-
-		parm_opt = tiniparser_getint(ctx->dict, key, -1);
-		TALLOC_FREE(key);
-
-		_pam_log_debug(ctx, LOG_INFO,
-			       "CONFIG file: %s '%d'\n",
-			       item, parm_opt);
-	}
-out:
-	return parm_opt;
+	return atoi(value);
 }
 
 static const char *get_krb5_cc_type_from_config(struct pwb_context *ctx)