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diff -up Linux-PAM-1.0.91/modules/pam_mkhomedir/pam_mkhomedir.c.std-noclose Linux-PAM-1.0.91/modules/pam_mkhomedir/pam_mkhomedir.c
--- Linux-PAM-1.0.91/modules/pam_mkhomedir/pam_mkhomedir.c.std-noclose 2009-03-03 14:56:01.000000000 +0100
+++ Linux-PAM-1.0.91/modules/pam_mkhomedir/pam_mkhomedir.c 2009-03-26 10:02:15.000000000 +0100
@@ -131,13 +131,21 @@ create_homedir (pam_handle_t *pamh, int
if (child == 0) {
int i;
struct rlimit rlim;
+ int dummyfds[2];
static char *envp[] = { NULL };
char *args[] = { NULL, NULL, NULL, NULL, NULL };
+ /* replace std file descriptors with a dummy pipe */
+ if (pipe(dummyfds) == 0) {
+ dup2(dummyfds[0], STDIN_FILENO);
+ dup2(dummyfds[1], STDOUT_FILENO);
+ dup2(dummyfds[1], STDERR_FILENO);
+ }
+
if (getrlimit(RLIMIT_NOFILE, &rlim)==0) {
if (rlim.rlim_max >= MAX_FD_NO)
rlim.rlim_max = MAX_FD_NO;
- for (i=0; i < (int)rlim.rlim_max; i++) {
+ for (i = STDERR_FILENO + 1; i < (int)rlim.rlim_max; i++) {
close(i);
}
}
diff -up Linux-PAM-1.0.91/modules/pam_unix/support.c.std-noclose Linux-PAM-1.0.91/modules/pam_unix/support.c
--- Linux-PAM-1.0.91/modules/pam_unix/support.c.std-noclose 2009-03-03 14:56:01.000000000 +0100
+++ Linux-PAM-1.0.91/modules/pam_unix/support.c 2009-03-26 10:08:59.000000000 +0100
@@ -443,13 +443,16 @@ static int _unix_run_helper_binary(pam_h
/* reopen stdin as pipe */
dup2(fds[0], STDIN_FILENO);
+ /* and replace also the stdout/err as the helper will
+ not write anything there */
+ dup2(fds[1], STDOUT_FILENO);
+ dup2(fds[1], STDERR_FILENO);
if (getrlimit(RLIMIT_NOFILE,&rlim)==0) {
if (rlim.rlim_max >= MAX_FD_NO)
rlim.rlim_max = MAX_FD_NO;
- for (i=0; i < (int)rlim.rlim_max; i++) {
- if (i != STDIN_FILENO)
- close(i);
+ for (i = STDERR_FILENO + 1; i < (int)rlim.rlim_max; i++) {
+ close(i);
}
}
diff -up Linux-PAM-1.0.91/modules/pam_unix/pam_unix_passwd.c.std-noclose Linux-PAM-1.0.91/modules/pam_unix/pam_unix_passwd.c
--- Linux-PAM-1.0.91/modules/pam_unix/pam_unix_passwd.c.std-noclose 2009-03-03 14:56:01.000000000 +0100
+++ Linux-PAM-1.0.91/modules/pam_unix/pam_unix_passwd.c 2009-03-26 10:07:06.000000000 +0100
@@ -175,13 +175,16 @@ static int _unix_run_update_binary(pam_h
/* reopen stdin as pipe */
dup2(fds[0], STDIN_FILENO);
+ /* and replace also the stdout/err as the helper will
+ not write anything there */
+ dup2(fds[1], STDOUT_FILENO);
+ dup2(fds[1], STDERR_FILENO);
if (getrlimit(RLIMIT_NOFILE,&rlim)==0) {
if (rlim.rlim_max >= MAX_FD_NO)
rlim.rlim_max = MAX_FD_NO;
- for (i=0; i < (int)rlim.rlim_max; i++) {
- if (i != STDIN_FILENO)
- close(i);
+ for (i = STDERR_FILENO + 1; i < (int)rlim.rlim_max; i++) {
+ close(i);
}
}
diff -up Linux-PAM-1.0.91/modules/pam_unix/pam_unix_acct.c.std-noclose Linux-PAM-1.0.91/modules/pam_unix/pam_unix_acct.c
--- Linux-PAM-1.0.91/modules/pam_unix/pam_unix_acct.c.std-noclose 2009-03-03 14:56:01.000000000 +0100
+++ Linux-PAM-1.0.91/modules/pam_unix/pam_unix_acct.c 2009-03-26 10:05:41.000000000 +0100
@@ -100,16 +100,18 @@ int _unix_run_verify_binary(pam_handle_t
/* reopen stdout as pipe */
dup2(fds[1], STDOUT_FILENO);
+ /* and replace also the stdin, stderr so we do not exec the helper with
+ tty as stdin, it will not read anything from there anyway */
+ dup2(fds[0], STDIN_FILENO);
+ dup2(fds[1], STDERR_FILENO);
/* XXX - should really tidy up PAM here too */
if (getrlimit(RLIMIT_NOFILE,&rlim)==0) {
if (rlim.rlim_max >= MAX_FD_NO)
rlim.rlim_max = MAX_FD_NO;
- for (i=0; i < (int)rlim.rlim_max; i++) {
- if (i != STDOUT_FILENO) {
- close(i);
- }
+ for (i = STDERR_FILENO + 1; i < (int)rlim.rlim_max; i++) {
+ close(i);
}
}
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