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|
On systems without setfsuid(), use setreuid() instead.
Authors: Steve Langasek <vorlon@debian.org>
Upstream status: superseded by pam_modutil_set_euid proposal
Index: Linux-PAM/modules/pam_xauth/pam_xauth.c
===================================================================
--- Linux-PAM/modules/pam_xauth/pam_xauth.c.orig
+++ Linux-PAM/modules/pam_xauth/pam_xauth.c
@@ -35,7 +35,9 @@
#include "config.h"
#include <sys/types.h>
+#ifdef HAVE_SYS_FSUID_H
#include <sys/fsuid.h>
+#endif /* HAVE_SYS_FSUID_H */
#include <sys/wait.h>
#include <errno.h>
#include <fnmatch.h>
@@ -210,6 +212,9 @@
FILE *fp;
int i;
uid_t euid;
+#ifndef HAVE_SYS_FSUID_H
+ uid_t uid;
+#endif
/* Check this user's <sense> file. */
pwd = pam_modutil_getpwnam(pamh, this_user);
if (pwd == NULL) {
@@ -226,9 +231,34 @@
return PAM_SESSION_ERR;
}
euid = geteuid();
+#ifdef HAVE_SYS_FSUID_H
setfsuid(pwd->pw_uid);
+#else
+ uid = getuid();
+ if (uid == pwd->pw_uid)
+ setreuid(euid, uid);
+ else {
+ setreuid(0, -1);
+ if (setreuid(-1, uid) == -1) {
+ setreuid(-1, 0);
+ setreuid(0, -1);
+ if (setreuid(-1, pwd->pw_uid))
+ return PAM_CRED_INSUFFICIENT;
+ }
+ }
+#endif
fp = fopen(path, "r");
+#ifdef HAVE_SYS_FSUID_H
setfsuid(euid);
+#else
+ if (uid == pwd->pw_uid)
+ setreuid(uid, euid);
+ else {
+ if (setreuid(-1, 0) == -1)
+ setreuid(uid, -1);
+ setreuid(-1, euid);
+ }
+#endif
if (fp != NULL) {
char buf[LINE_MAX], *tmp;
/* Scan the file for a list of specs of users to "trust". */
@@ -297,6 +327,9 @@
int fd, i, debug = 0;
int retval = PAM_SUCCESS;
uid_t systemuser = 499, targetuser = 0, euid;
+#ifndef HAVE_SYS_FSUID_H
+ uid_t uid;
+#endif
/* Parse arguments. We don't understand many, so no sense in breaking
* this into a separate function. */
@@ -541,9 +574,34 @@
/* Generate a new file to hold the data. */
euid = geteuid();
+#ifdef HAVE_SYS_FSUID_H
setfsuid(tpwd->pw_uid);
+#else
+ uid = getuid();
+ if (uid == tpwd->pw_uid)
+ setreuid(euid, uid);
+ else {
+ setreuid(0, -1);
+ if (setreuid(-1, uid) == -1) {
+ setreuid(-1, 0);
+ setreuid(0, -1);
+ if (setreuid(-1, tpwd->pw_uid))
+ return PAM_CRED_INSUFFICIENT;
+ }
+ }
+#endif
fd = mkstemp(xauthority + strlen(XAUTHENV) + 1);
+#ifdef HAVE_SYS_FSUID_H
setfsuid(euid);
+#else
+ if (uid == tpwd->pw_uid)
+ setreuid(uid, euid);
+ else {
+ if (setreuid(-1, 0) == -1)
+ setreuid(uid, -1);
+ setreuid(-1, euid);
+ }
+#endif
if (fd == -1) {
pam_syslog(pamh, LOG_ERR,
"error creating temporary file `%s': %m",
|
