X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fkmod.c;h=bb4e29d924e4ff29567a962e7b643e0c1c875896;hb=eea2078eaf2bcd4e5e8b2e08798071efedac5e17;hp=44166e3bb8afab469a61575946b46da45e215cc7;hpb=59a49e38711a146dc0bef4837c825b5422335460;p=linux-2.6-omap-h63xx.git

diff --git a/kernel/kmod.c b/kernel/kmod.c
index 44166e3bb8a..bb4e29d924e 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -18,9 +18,6 @@
 	call_usermodehelper wait flag, and remove exec_usermodehelper.
 	Rusty Russell <rusty@rustcorp.com.au>  Jan 2003
 */
-#define __KERNEL_SYSCALLS__
-
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/syscalls.h>
@@ -36,6 +33,7 @@
 #include <linux/mount.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
+#include <linux/resource.h>
 #include <asm/uaccess.h>
 
 extern int max_threads;
@@ -123,6 +121,7 @@ struct subprocess_info {
 	struct key *ring;
 	int wait;
 	int retval;
+	struct file *stdin;
 };
 
 /*
@@ -131,14 +130,14 @@ struct subprocess_info {
 static int ____call_usermodehelper(void *data)
 {
 	struct subprocess_info *sub_info = data;
-	struct key *old_session;
+	struct key *new_session, *old_session;
 	int retval;
 
 	/* Unblock all signals and set the session keyring. */
-	key_get(sub_info->ring);
+	new_session = key_get(sub_info->ring);
 	flush_signals(current);
 	spin_lock_irq(&current->sighand->siglock);
-	old_session = __install_session_keyring(current, sub_info->ring);
+	old_session = __install_session_keyring(current, new_session);
 	flush_signal_handlers(current, 1);
 	sigemptyset(&current->blocked);
 	recalc_sigpending();
@@ -146,12 +145,30 @@ static int ____call_usermodehelper(void *data)
 
 	key_put(old_session);
 
+	/* Install input pipe when needed */
+	if (sub_info->stdin) {
+		struct files_struct *f = current->files;
+		struct fdtable *fdt;
+		/* no races because files should be private here */
+		sys_close(0);
+		fd_install(0, sub_info->stdin);
+		spin_lock(&f->file_lock);
+		fdt = files_fdtable(f);
+		FD_SET(0, fdt->open_fds);
+		FD_CLR(0, fdt->close_on_exec);
+		spin_unlock(&f->file_lock);
+
+		/* and disallow core files too */
+		current->signal->rlim[RLIMIT_CORE] = (struct rlimit){0, 0};
+	}
+
 	/* We can run anywhere, unlike our parent keventd(). */
 	set_cpus_allowed(current, CPU_MASK_ALL);
 
 	retval = -EPERM;
 	if (current->fs->root)
-		retval = execve(sub_info->path, sub_info->argv,sub_info->envp);
+		retval = kernel_execve(sub_info->path,
+				sub_info->argv, sub_info->envp);
 
 	/* Exec failed? */
 	sub_info->retval = retval;
@@ -170,13 +187,15 @@ static int wait_for_helper(void *data)
 	sa.sa.sa_handler = SIG_IGN;
 	sa.sa.sa_flags = 0;
 	siginitset(&sa.sa.sa_mask, sigmask(SIGCHLD));
-	do_sigaction(SIGCHLD, &sa, (struct k_sigaction *)0);
+	do_sigaction(SIGCHLD, &sa, NULL);
 	allow_signal(SIGCHLD);
 
 	pid = kernel_thread(____call_usermodehelper, sub_info, SIGCHLD);
 	if (pid < 0) {
 		sub_info->retval = pid;
 	} else {
+		int ret;
+
 		/*
 		 * Normally it is bogus to call wait4() from in-kernel because
 		 * wait4() wants to write the exit code to a userspace address.
@@ -186,7 +205,15 @@ static int wait_for_helper(void *data)
 		 *
 		 * Thus the __user pointer cast is valid here.
 		 */
-		sys_wait4(pid, (int __user *) &sub_info->retval, 0, NULL);
+		sys_wait4(pid, (int __user *)&ret, 0, NULL);
+
+		/*
+		 * If ret is 0, either ____call_usermodehelper failed and the
+		 * real error code is already in sub_info->retval or
+		 * sub_info->retval is 0 anyway, so don't mess with it then.
+		 */
+		if (ret)
+			sub_info->retval = ret;
 	}
 
 	complete(sub_info->complete);
@@ -198,11 +225,12 @@ static void __call_usermodehelper(void *data)
 {
 	struct subprocess_info *sub_info = data;
 	pid_t pid;
+	int wait = sub_info->wait;
 
 	/* CLONE_VFORK: wait until the usermode helper has execve'd
 	 * successfully We need the data structures to stay around
 	 * until that is done.  */
-	if (sub_info->wait)
+	if (wait)
 		pid = kernel_thread(wait_for_helper, sub_info,
 				    CLONE_FS | CLONE_FILES | SIGCHLD);
 	else
@@ -212,7 +240,7 @@ static void __call_usermodehelper(void *data)
 	if (pid < 0) {
 		sub_info->retval = pid;
 		complete(sub_info->complete);
-	} else if (!sub_info->wait)
+	} else if (!wait)
 		complete(sub_info->complete);
 }
 
@@ -234,7 +262,7 @@ static void __call_usermodehelper(void *data)
 int call_usermodehelper_keys(char *path, char **argv, char **envp,
 			     struct key *session_keyring, int wait)
 {
-	DECLARE_COMPLETION(done);
+	DECLARE_COMPLETION_ONSTACK(done);
 	struct subprocess_info sub_info = {
 		.complete	= &done,
 		.path		= path,
@@ -258,6 +286,44 @@ int call_usermodehelper_keys(char *path, char **argv, char **envp,
 }
 EXPORT_SYMBOL(call_usermodehelper_keys);
 
+int call_usermodehelper_pipe(char *path, char **argv, char **envp,
+			     struct file **filp)
+{
+	DECLARE_COMPLETION(done);
+	struct subprocess_info sub_info = {
+		.complete	= &done,
+		.path		= path,
+		.argv		= argv,
+		.envp		= envp,
+		.retval		= 0,
+	};
+	struct file *f;
+	DECLARE_WORK(work, __call_usermodehelper, &sub_info);
+
+	if (!khelper_wq)
+		return -EBUSY;
+
+	if (path[0] == '\0')
+		return 0;
+
+	f = create_write_pipe();
+	if (!f)
+		return -ENOMEM;
+	*filp = f;
+
+	f = create_read_pipe(f);
+	if (!f) {
+		free_write_pipe(*filp);
+		return -ENOMEM;
+	}
+	sub_info.stdin = f;
+
+	queue_work(khelper_wq, &work);
+	wait_for_completion(&done);
+	return sub_info.retval;
+}
+EXPORT_SYMBOL(call_usermodehelper_pipe);
+
 void __init usermodehelper_init(void)
 {
 	khelper_wq = create_singlethread_workqueue("khelper");