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/include/linux/kobject.h b/include/linux/kobject.h
index 949706c..626bdd3 100644
--- a/include/linux/kobject.h
+++ b/include/linux/kobject.h
@@ -29,6 +29,8 @@
#define KOBJ_NAME_LEN 20
#define UEVENT_HELPER_PATH_LEN 256
+#define UEVENT_NUM_ENVP 32 /* number of env pointers */
+#define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */
/* path to the userspace helper executed on an event */
extern char uevent_helper[];
@@ -111,11 +113,18 @@
struct attribute ** default_attrs;
};
+struct kobj_uevent_env {
+ char *envp[UEVENT_NUM_ENVP];
+ int envp_idx;
+ char buf[UEVENT_BUFFER_SIZE];
+ int buflen;
+};
+
struct kset_uevent_ops {
int (*filter)(struct kset *kset, struct kobject *kobj);
const char *(*name)(struct kset *kset, struct kobject *kobj);
- int (*uevent)(struct kset *kset, struct kobject *kobj, char **envp,
- int num_envp, char *buffer, int buffer_size);
+ int (*uevent)(struct kset *kset, struct kobject *kobj,
+ struct kobj_uevent_env *env);
};
/*
@@ -275,10 +284,8 @@
int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
char *envp[]);
-int add_uevent_var(char **envp, int num_envp, int *cur_index,
- char *buffer, int buffer_size, int *cur_len,
- const char *format, ...)
- __attribute__((format (printf, 7, 8)));
+int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
+ __attribute__((format (printf, 2, 3)));
#else
static inline int kobject_uevent(struct kobject *kobj, enum kobject_action action)
{ return 0; }
@@ -287,9 +294,7 @@
char *envp[])
{ return 0; }
-static inline int add_uevent_var(char **envp, int num_envp, int *cur_index,
- char *buffer, int buffer_size, int *cur_len,
- const char *format, ...)
+static inline int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
{ return 0; }
#endif