From: tedu <tedu@openbsd.org>
Date: Thu, 15 Feb 2024 18:57:58 +0000 (+0000)
Subject: change permit to be more bits away from deny, because rowhammer.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=38599afa1d1d1f14a897b01350e8ce94486e1788;p=openbsd

change permit to be more bits away from deny, because rowhammer.
not really sure why this is our problem, but the diff is small.
ok deraadt millert miod
---

diff --git a/usr.bin/doas/doas.c b/usr.bin/doas/doas.c
index 8b684d6006c..3999b2e2f64 100644
--- a/usr.bin/doas/doas.c
+++ b/usr.bin/doas/doas.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: doas.c,v 1.98 2022/12/22 19:53:22 kn Exp $ */
+/* $OpenBSD: doas.c,v 1.99 2024/02/15 18:57:58 tedu Exp $ */
 /*
  * Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
  *
@@ -145,8 +145,10 @@ permit(uid_t uid, gid_t *groups, int ngroups, const struct rule **lastr,
 			*lastr = rules[i];
 	}
 	if (!*lastr)
+		return -1;
+	if ((*lastr)->action == PERMIT)
 		return 0;
-	return (*lastr)->action == PERMIT;
+	return -1;
 }
 
 static void
@@ -181,6 +183,7 @@ checkconfig(const char *confpath, int argc, char **argv,
     uid_t uid, gid_t *groups, int ngroups, uid_t target)
 {
 	const struct rule *rule;
+	int rv;
 
 	setresuid(uid, uid, uid);
 	if (pledge("stdio rpath getpw", NULL) == -1)
@@ -188,9 +191,9 @@ checkconfig(const char *confpath, int argc, char **argv,
 	parseconfig(confpath, 0);
 	if (!argc)
 		exit(0);
-
-	if (permit(uid, groups, ngroups, &rule, target, argv[0],
-	    (const char **)argv + 1)) {
+	rv = permit(uid, groups, ngroups, &rule, target, argv[0],
+ 	    (const char **)argv + 1);
+	if (rv == 0) {
 		printf("permit%s\n", (rule->options & NOPASS) ? " nopass" : "");
 		exit(0);
 	} else {
@@ -412,8 +415,9 @@ main(int argc, char **argv)
 	}
 
 	cmd = argv[0];
-	if (!permit(uid, groups, ngroups, &rule, target, cmd,
-	    (const char **)argv + 1)) {
+	rv = permit(uid, groups, ngroups, &rule, target, cmd,
+	    (const char **)argv + 1);
+	if (rv != 0) {
 		syslog(LOG_AUTHPRIV | LOG_NOTICE,
 		    "command not permitted for %s: %s", mypw->pw_name, cmdline);
 		errc(1, EPERM, NULL);
diff --git a/usr.bin/doas/doas.h b/usr.bin/doas/doas.h
index b98fe353b18..ce6a03618ac 100644
--- a/usr.bin/doas/doas.h
+++ b/usr.bin/doas/doas.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: doas.h,v 1.19 2021/11/30 20:08:15 tobias Exp $ */
+/* $OpenBSD: doas.h,v 1.20 2024/02/15 18:57:58 tedu Exp $ */
 /*
  * Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
  *
@@ -36,7 +36,7 @@ struct passwd;
 char **prepenv(const struct rule *, const struct passwd *,
     const struct passwd *);
 
-#define PERMIT	1
+#define PERMIT	-1
 #define DENY	2
 
 #define NOPASS		0x1