From 281100560056e06f69d2cdb4dcc854bd3717734f Mon Sep 17 00:00:00 2001
From: Michal Sekletar <msekleta@redhat.com>
Date: Mon, 10 Feb 2014 17:41:32 +0100
Subject: [PATCH] pam: do not set XDG_RUNTIME_DIR unconditionally
If the session's original user is not the same as the newly logged in one we
will not set XDG_RUNTIME_DIR.
Patch based on upstream commit baae0358f349870544884e405e82e4be7d8add9f
---
src/login/logind-dbus.c | 2 ++
src/login/logind-session-dbus.c | 1 +
src/login/pam-module.c | 52 ++++++++++++++++++++---------------------
3 files changed, 29 insertions(+), 26 deletions(-)
diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c
index bb85c7d..69e94aa 100644
--- a/src/login/logind-dbus.c
+++ b/src/login/logind-dbus.c
@@ -90,6 +90,7 @@
" <arg name=\"path\" type=\"o\" direction=\"out\"/>\n" \
" <arg name=\"runtime_path\" type=\"o\" direction=\"out\"/>\n" \
" <arg name=\"fd\" type=\"h\" direction=\"out\"/>\n" \
+ " <arg name=\"uid\" type=\"u\" direction=\"out\"/>\n" \
" <arg name=\"seat\" type=\"s\" direction=\"out\"/>\n" \
" <arg name=\"vtnr\" type=\"u\" direction=\"out\"/>\n" \
" <arg name=\"existing\" type=\"b\" direction=\"out\"/>\n" \
@@ -523,6 +524,7 @@ static int bus_manager_create_session(Manager *m, DBusMessage *message) {
DBUS_TYPE_OBJECT_PATH, &path,
DBUS_TYPE_STRING, &session->user->runtime_path,
DBUS_TYPE_UNIX_FD, &fifo_fd,
+ DBUS_TYPE_UINT32, &session->user->uid,
DBUS_TYPE_STRING, &cseat,
DBUS_TYPE_UINT32, &vtnr,
DBUS_TYPE_BOOLEAN, &exists,
diff --git a/src/login/logind-session-dbus.c b/src/login/logind-session-dbus.c
index be4e01c..86b0746 100644
--- a/src/login/logind-session-dbus.c
+++ b/src/login/logind-session-dbus.c
@@ -755,6 +755,7 @@ int session_send_create_reply(Session *s, DBusError *error) {
DBUS_TYPE_OBJECT_PATH, &path,
DBUS_TYPE_STRING, &s->user->runtime_path,
DBUS_TYPE_UNIX_FD, &fifo_fd,
+ DBUS_TYPE_UINT32, &s->user->uid,
DBUS_TYPE_STRING, &cseat,
DBUS_TYPE_UINT32, &vtnr,
DBUS_TYPE_BOOLEAN, &exists,
diff --git a/src/login/pam-module.c b/src/login/pam-module.c
index 02f1618..22d9733 100644
--- a/src/login/pam-module.c
+++ b/src/login/pam-module.c
@@ -86,31 +86,24 @@ static int get_user_data(
const char *username = NULL;
struct passwd *pw = NULL;
- uid_t uid;
int r;
assert(handle);
assert(ret_username);
assert(ret_pw);
- r = audit_loginuid_from_pid(0, &uid);
- if (r >= 0)
- pw = pam_modutil_getpwuid(handle, uid);
- else {
- r = pam_get_user(handle, &username, NULL);
- if (r != PAM_SUCCESS) {
- pam_syslog(handle, LOG_ERR, "Failed to get user name.");
- return r;
- }
-
- if (isempty(username)) {
- pam_syslog(handle, LOG_ERR, "User name not valid.");
- return PAM_AUTH_ERR;
- }
+ r = pam_get_user(handle, &username, NULL);
+ if (r != PAM_SUCCESS) {
+ pam_syslog(handle, LOG_ERR, "Failed to get user name.");
+ return r;
+ }
- pw = pam_modutil_getpwnam(handle, username);
+ if (isempty(username)) {
+ pam_syslog(handle, LOG_ERR, "User name not valid.");
+ return PAM_AUTH_ERR;
}
+ pw = pam_modutil_getpwnam(handle, username);
if (!pw) {
pam_syslog(handle, LOG_ERR, "Failed to get user data.");
return PAM_USER_UNKNOWN;
@@ -123,16 +116,14 @@ static int get_user_data(
}
static int get_seat_from_display(const char *display, const char **seat, uint32_t *vtnr) {
- _cleanup_free_ char *p = NULL;
- int r;
+ _cleanup_free_ char *p = NULL, *tty=NULL;
_cleanup_close_ int fd = -1;
union sockaddr_union sa = {
.un.sun_family = AF_UNIX,
};
struct ucred ucred;
socklen_t l;
- _cleanup_free_ char *tty = NULL;
- int v;
+ int v, r;
assert(display);
assert(vtnr);
@@ -186,14 +177,14 @@ _public_ PAM_EXTERN int pam_sm_open_session(
bool debug = false;
const char *username, *id, *object_path, *runtime_path, *service = NULL, *tty = NULL, *display = NULL, *remote_user = NULL, *remote_host = NULL, *seat = NULL, *type = NULL, *class = NULL, *class_pam = NULL, *cvtnr = NULL;
DBusError error;
- uint32_t uid, pid;
DBusMessageIter iter;
int session_fd = -1;
DBusConnection *bus = NULL;
DBusMessage *m = NULL, *reply = NULL;
dbus_bool_t remote, existing;
int r;
- uint32_t vtnr = 0;
+ uint32_t uid, pid, vtnr = 0;
+ uid_t original_uid;
assert(handle);
@@ -389,6 +380,7 @@ _public_ PAM_EXTERN int pam_sm_open_session(
DBUS_TYPE_OBJECT_PATH, &object_path,
DBUS_TYPE_STRING, &runtime_path,
DBUS_TYPE_UNIX_FD, &session_fd,
+ DBUS_TYPE_UINT32, &original_uid,
DBUS_TYPE_STRING, &seat,
DBUS_TYPE_UINT32, &vtnr,
DBUS_TYPE_BOOLEAN, &existing,
@@ -409,10 +401,18 @@ _public_ PAM_EXTERN int pam_sm_open_session(
goto finish;
}
- r = pam_misc_setenv(handle, "XDG_RUNTIME_DIR", runtime_path, 0);
- if (r != PAM_SUCCESS) {
- pam_syslog(handle, LOG_ERR, "Failed to set runtime dir.");
- goto finish;
+ if (original_uid == pw->pw_uid) {
+ /* Don't set $XDG_RUNTIME_DIR if the user we now
+ * authenticated for does not match the original user
+ * of the session. We do this in order not to result
+ * in privileged apps clobbering the runtime directory
+ * unnecessarily. */
+
+ r = pam_misc_setenv(handle, "XDG_RUNTIME_DIR", runtime_path, 0);
+ if (r != PAM_SUCCESS) {
+ pam_syslog(handle, LOG_ERR, "Failed to set runtime dir.");
+ return r;
+ }
}
if (!isempty(seat)) {