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/input/input.c b/drivers/input/input.c
index 5fe7555..5dc361c 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -859,87 +859,66 @@
* Input uevent interface - loading event handlers based on
* device bitfields.
*/
-static int input_add_uevent_bm_var(char **envp, int num_envp, int *cur_index,
- char *buffer, int buffer_size, int *cur_len,
+static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
const char *name, unsigned long *bitmap, int max)
{
- if (*cur_index >= num_envp - 1)
+ int len;
+
+ if (add_uevent_var(env, "%s=", name))
return -ENOMEM;
- envp[*cur_index] = buffer + *cur_len;
-
- *cur_len += snprintf(buffer + *cur_len, max(buffer_size - *cur_len, 0), name);
- if (*cur_len >= buffer_size)
+ len = input_print_bitmap(&env->buf[env->buflen - 1],
+ sizeof(env->buf) - env->buflen,
+ bitmap, max, 0);
+ if (len >= (sizeof(env->buf) - env->buflen))
return -ENOMEM;
- *cur_len += input_print_bitmap(buffer + *cur_len,
- max(buffer_size - *cur_len, 0),
- bitmap, max, 0) + 1;
- if (*cur_len > buffer_size)
- return -ENOMEM;
-
- (*cur_index)++;
+ env->buflen += len;
return 0;
}
-static int input_add_uevent_modalias_var(char **envp, int num_envp, int *cur_index,
- char *buffer, int buffer_size, int *cur_len,
+static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
struct input_dev *dev)
{
- if (*cur_index >= num_envp - 1)
+ int len;
+
+ if (add_uevent_var(env, "MODALIAS="))
return -ENOMEM;
- envp[*cur_index] = buffer + *cur_len;
-
- *cur_len += snprintf(buffer + *cur_len, max(buffer_size - *cur_len, 0),
- "MODALIAS=");
- if (*cur_len >= buffer_size)
+ len = input_print_modalias(&env->buf[env->buflen - 1],
+ sizeof(env->buf) - env->buflen,
+ dev, 0);
+ if (len >= (sizeof(env->buf) - env->buflen))
return -ENOMEM;
- *cur_len += input_print_modalias(buffer + *cur_len,
- max(buffer_size - *cur_len, 0),
- dev, 0) + 1;
- if (*cur_len > buffer_size)
- return -ENOMEM;
-
- (*cur_index)++;
+ env->buflen += len;
return 0;
}
#define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
do { \
- int err = add_uevent_var(envp, num_envp, &i, \
- buffer, buffer_size, &len, \
- fmt, val); \
+ int err = add_uevent_var(env, fmt, val); \
if (err) \
return err; \
} while (0)
#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
do { \
- int err = input_add_uevent_bm_var(envp, num_envp, &i, \
- buffer, buffer_size, &len, \
- name, bm, max); \
+ int err = input_add_uevent_bm_var(env, name, bm, max); \
if (err) \
return err; \
} while (0)
#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
do { \
- int err = input_add_uevent_modalias_var(envp, \
- num_envp, &i, \
- buffer, buffer_size, &len, \
- dev); \
+ int err = input_add_uevent_modalias_var(env, dev); \
if (err) \
return err; \
} while (0)
-static int input_dev_uevent(struct device *device, char **envp,
- int num_envp, char *buffer, int buffer_size)
+static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
{
struct input_dev *dev = to_input_dev(device);
- int i = 0;
- int len = 0;
INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
dev->id.bustype, dev->id.vendor,
@@ -971,7 +950,6 @@
INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
- envp[i] = NULL;
return 0;
}