Driver core: let request_module() send a /sys/modules/kmod/-uevent

On recent systems, calls to /sbin/modprobe are handled by udev depending
on the kind of device the kernel has discovered. This patch creates an
uevent for the kernels internal request_module(), to let udev take control
over the request, instead of forking the binary directly by the kernel.
The direct execution of /sbin/modprobe can be disabled by setting:
  /sys/module/kmod/mod_request_helper (/proc/sys/kernel/modprobe)
to an empty string, the same way /proc/sys/kernel/hotplug is disabled on an
udev system.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 16 insertions, 10 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 8a94e054230c..225501f620ff 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -653,20 +653,11 @@ static void wait_for_zero_refcount(struct module *mod)
 	mutex_lock(&module_mutex);
 }
 
-asmlinkage long
-sys_delete_module(const char __user *name_user, unsigned int flags)
+int delete_module(const char *name, unsigned int flags)
 {
 	struct module *mod;
-	char name[MODULE_NAME_LEN];
 	int ret, forced = 0;
 
-	if (!capable(CAP_SYS_MODULE))
-		return -EPERM;
-
-	if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
-		return -EFAULT;
-	name[MODULE_NAME_LEN-1] = '\0';
-
 	if (mutex_lock_interruptible(&module_mutex) != 0)
 		return -EINTR;
 
@@ -727,6 +718,21 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
 	return ret;
 }
 
+asmlinkage long
+sys_delete_module(const char __user *name_user, unsigned int flags)
+{
+	char name[MODULE_NAME_LEN];
+
+	if (!capable(CAP_SYS_MODULE))
+		return -EPERM;
+
+	if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
+		return -EFAULT;
+	name[MODULE_NAME_LEN-1] = '\0';
+
+	return delete_module(name, flags);
+}
+
 static void print_unload_info(struct seq_file *m, struct module *mod)
 {
 	struct module_use *use;