Driver core: change add_uevent_var to use a struct
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.
Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/base/core.c b/drivers/base/core.c
index ec86d6f..d487c03 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -141,33 +141,23 @@
return NULL;
}
-static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp,
- int num_envp, char *buffer, int buffer_size)
+static int dev_uevent(struct kset *kset, struct kobject *kobj,
+ struct kobj_uevent_env *env)
{
struct device *dev = to_dev(kobj);
- int i = 0;
- int length = 0;
int retval = 0;
/* add the major/minor if present */
if (MAJOR(dev->devt)) {
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "MAJOR=%u", MAJOR(dev->devt));
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "MINOR=%u", MINOR(dev->devt));
+ add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt));
+ add_uevent_var(env, "MINOR=%u", MINOR(dev->devt));
}
if (dev->type && dev->type->name)
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "DEVTYPE=%s", dev->type->name);
+ add_uevent_var(env, "DEVTYPE=%s", dev->type->name);
if (dev->driver)
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "DRIVER=%s", dev->driver->name);
+ add_uevent_var(env, "DRIVER=%s", dev->driver->name);
#ifdef CONFIG_SYSFS_DEPRECATED
if (dev->class) {
@@ -181,59 +171,43 @@
path = kobject_get_path(&parent->kobj, GFP_KERNEL);
if (path) {
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVPATH=%s", path);
+ add_uevent_var(env, "PHYSDEVPATH=%s", path);
kfree(path);
}
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVBUS=%s", parent->bus->name);
+ add_uevent_var(env, "PHYSDEVBUS=%s", parent->bus->name);
if (parent->driver)
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVDRIVER=%s", parent->driver->name);
+ add_uevent_var(env, "PHYSDEVDRIVER=%s",
+ parent->driver->name);
}
} else if (dev->bus) {
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVBUS=%s", dev->bus->name);
+ add_uevent_var(env, "PHYSDEVBUS=%s", dev->bus->name);
if (dev->driver)
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVDRIVER=%s", dev->driver->name);
+ add_uevent_var(env, "PHYSDEVDRIVER=%s", dev->driver->name);
}
#endif
- /* terminate, set to next free slot, shrink available space */
- envp[i] = NULL;
- envp = &envp[i];
- num_envp -= i;
- buffer = &buffer[length];
- buffer_size -= length;
-
+ /* have the bus specific function add its stuff */
if (dev->bus && dev->bus->uevent) {
- /* have the bus specific function add its stuff */
- retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size);
+ retval = dev->bus->uevent(dev, env);
if (retval)
pr_debug ("%s: bus uevent() returned %d\n",
__FUNCTION__, retval);
}
+ /* have the class specific function add its stuff */
if (dev->class && dev->class->dev_uevent) {
- /* have the class specific function add its stuff */
- retval = dev->class->dev_uevent(dev, envp, num_envp, buffer, buffer_size);
+ retval = dev->class->dev_uevent(dev, env);
if (retval)
pr_debug("%s: class uevent() returned %d\n",
__FUNCTION__, retval);
}
+ /* have the device type specific fuction add its stuff */
if (dev->type && dev->type->uevent) {
- /* have the device type specific fuction add its stuff */
- retval = dev->type->uevent(dev, envp, num_envp, buffer, buffer_size);
+ retval = dev->type->uevent(dev, env);
if (retval)
pr_debug("%s: dev_type uevent() returned %d\n",
__FUNCTION__, retval);
@@ -253,9 +227,7 @@
{
struct kobject *top_kobj;
struct kset *kset;
- char *envp[32];
- char *data = NULL;
- char *pos;
+ struct kobj_uevent_env *env = NULL;
int i;
size_t count = 0;
int retval;
@@ -278,26 +250,20 @@
if (!kset->uevent_ops->filter(kset, &dev->kobj))
goto out;
- data = (char *)get_zeroed_page(GFP_KERNEL);
- if (!data)
+ env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
+ if (!env)
return -ENOMEM;
/* let the kset specific function add its keys */
- pos = data;
- memset(envp, 0, sizeof(envp));
- retval = kset->uevent_ops->uevent(kset, &dev->kobj,
- envp, ARRAY_SIZE(envp),
- pos, PAGE_SIZE);
+ retval = kset->uevent_ops->uevent(kset, &dev->kobj, env);
if (retval)
goto out;
/* copy keys to file */
- for (i = 0; envp[i]; i++) {
- pos = &buf[count];
- count += sprintf(pos, "%s\n", envp[i]);
- }
+ for (i = 0; i < env->envp_idx; i++)
+ count += sprintf(&buf[count], "%s\n", env->envp[i]);
out:
- free_page((unsigned long)data);
+ kfree(env);
return count;
}