From 88da20ee56491fc6c38c26810c95e199f51fb71d Mon Sep 17 00:00:00 2001
From: "Andrew G. Morgan" <morgan@kernel.org>
Date: Sat, 27 Nov 2021 21:00:22 -0800
Subject: Complete Linux-PAM compliance for forked child in su and login.
As documented here:
http://www.linux-pam.org/Linux-PAM-html/adg-interface-by-app-expected.html#adg-pam_end
The child that is about to exec*() the user shell is supposed to pam_end()
with PAM_DATA_SILENT. This gives the modules a last chance to do a minor
cleanup of the module state before the user's shell is launched.
Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=2037212
Upstream: http://github.com/util-linux/util-linux/commit/4660286e9cdff6d95b49295674b96f83af10ea36
Signed-off-by: Andrew G. Morgan <morgan@kernel.org>
---
login-utils/login.c | 3 +++
login-utils/su-common.c | 3 +++
2 files changed, 6 insertions(+)
diff --git a/login-utils/login.c b/login-utils/login.c
index 3657f04cd..c62e91e94 100644
--- a/login-utils/login.c
+++ b/login-utils/login.c
@@ -1521,6 +1521,9 @@ int main(int argc, char **argv)
child_argv[child_argc++] = NULL;
+ /* http://www.linux-pam.org/Linux-PAM-html/adg-interface-by-app-expected.html#adg-pam_end */
+ (void) pam_end(cxt.pamh, PAM_SUCCESS|PAM_DATA_SILENT);
+
execvp(child_argv[0], child_argv + 1);
if (!strcmp(child_argv[0], "/bin/sh"))
diff --git a/login-utils/su-common.c b/login-utils/su-common.c
index afd0ea8ad..7d4826bbc 100644
--- a/login-utils/su-common.c
+++ b/login-utils/su-common.c
@@ -1231,6 +1231,9 @@ int su_main(int argc, char **argv, int mode)
if (su->simulate_login && chdir(su->pwd->pw_dir) != 0)
warn(_("warning: cannot change directory to %s"), su->pwd->pw_dir);
+ /* http://www.linux-pam.org/Linux-PAM-html/adg-interface-by-app-expected.html#adg-pam_end */
+ (void) pam_end(su->pamh, PAM_SUCCESS|PAM_DATA_SILENT);
+
if (shell)
run_shell(su, shell, command, argv + optind, max(0, argc - optind));
--
2.34.1