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-rw-r--r--include/linux/kmod.h51
-rw-r--r--kernel/kmod.c51
-rw-r--r--kernel/sys.c6
3 files changed, 73 insertions, 35 deletions
diff --git a/include/linux/kmod.h b/include/linux/kmod.h
index facb27fe7de..f9edf63e90e 100644
--- a/include/linux/kmod.h
+++ b/include/linux/kmod.h
@@ -23,6 +23,7 @@
#include <linux/stddef.h>
#include <linux/errno.h>
#include <linux/compiler.h>
+#include <linux/workqueue.h>
#define KMOD_PATH_LEN 256
@@ -45,7 +46,27 @@ static inline int request_module_nowait(const char *name, ...) { return -ENOSYS;
struct key;
struct file;
-struct subprocess_info;
+
+enum umh_wait {
+ UMH_NO_WAIT = -1, /* don't wait at all */
+ UMH_WAIT_EXEC = 0, /* wait for the exec, but not the process */
+ UMH_WAIT_PROC = 1, /* wait for the process to complete */
+};
+
+struct subprocess_info {
+ struct work_struct work;
+ struct completion *complete;
+ struct cred *cred;
+ char *path;
+ char **argv;
+ char **envp;
+ enum umh_wait wait;
+ int retval;
+ struct file *stdin;
+ int (*init)(struct subprocess_info *info);
+ void (*cleanup)(struct subprocess_info *info);
+ void *data;
+};
/* Allocate a subprocess_info structure */
struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
@@ -56,14 +77,10 @@ void call_usermodehelper_setkeys(struct subprocess_info *info,
struct key *session_keyring);
int call_usermodehelper_stdinpipe(struct subprocess_info *sub_info,
struct file **filp);
-void call_usermodehelper_setcleanup(struct subprocess_info *info,
- void (*cleanup)(char **argv, char **envp));
-
-enum umh_wait {
- UMH_NO_WAIT = -1, /* don't wait at all */
- UMH_WAIT_EXEC = 0, /* wait for the exec, but not the process */
- UMH_WAIT_PROC = 1, /* wait for the process to complete */
-};
+void call_usermodehelper_setfns(struct subprocess_info *info,
+ int (*init)(struct subprocess_info *info),
+ void (*cleanup)(struct subprocess_info *info),
+ void *data);
/* Actually execute the sub-process */
int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
@@ -73,18 +90,32 @@ int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
void call_usermodehelper_freeinfo(struct subprocess_info *info);
static inline int
-call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
+call_usermodehelper_fns(char *path, char **argv, char **envp,
+ enum umh_wait wait,
+ int (*init)(struct subprocess_info *info),
+ void (*cleanup)(struct subprocess_info *), void *data)
{
struct subprocess_info *info;
gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
+
if (info == NULL)
return -ENOMEM;
+
+ call_usermodehelper_setfns(info, init, cleanup, data);
+
return call_usermodehelper_exec(info, wait);
}
static inline int
+call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
+{
+ return call_usermodehelper_fns(path, argv, envp, wait,
+ NULL, NULL, NULL);
+}
+
+static inline int
call_usermodehelper_keys(char *path, char **argv, char **envp,
struct key *session_keyring, enum umh_wait wait)
{
diff --git a/kernel/kmod.c b/kernel/kmod.c
index bf0e231d970..531ef62cf53 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -116,27 +116,16 @@ int __request_module(bool wait, const char *fmt, ...)
trace_module_request(module_name, wait, _RET_IP_);
- ret = call_usermodehelper(modprobe_path, argv, envp,
- wait ? UMH_WAIT_PROC : UMH_WAIT_EXEC);
+ ret = call_usermodehelper_fns(modprobe_path, argv, envp,
+ wait ? UMH_WAIT_PROC : UMH_WAIT_EXEC,
+ NULL, NULL, NULL);
+
atomic_dec(&kmod_concurrent);
return ret;
}
EXPORT_SYMBOL(__request_module);
#endif /* CONFIG_MODULES */
-struct subprocess_info {
- struct work_struct work;
- struct completion *complete;
- struct cred *cred;
- char *path;
- char **argv;
- char **envp;
- enum umh_wait wait;
- int retval;
- struct file *stdin;
- void (*cleanup)(char **argv, char **envp);
-};
-
/*
* This is the task which runs the usermode application
*/
@@ -184,9 +173,16 @@ static int ____call_usermodehelper(void *data)
*/
set_user_nice(current, 0);
+ if (sub_info->init) {
+ retval = sub_info->init(sub_info);
+ if (retval)
+ goto fail;
+ }
+
retval = kernel_execve(sub_info->path, sub_info->argv, sub_info->envp);
/* Exec failed? */
+fail:
sub_info->retval = retval;
do_exit(0);
}
@@ -194,7 +190,7 @@ static int ____call_usermodehelper(void *data)
void call_usermodehelper_freeinfo(struct subprocess_info *info)
{
if (info->cleanup)
- (*info->cleanup)(info->argv, info->envp);
+ (*info->cleanup)(info);
if (info->cred)
put_cred(info->cred);
kfree(info);
@@ -406,21 +402,31 @@ void call_usermodehelper_setkeys(struct subprocess_info *info,
EXPORT_SYMBOL(call_usermodehelper_setkeys);
/**
- * call_usermodehelper_setcleanup - set a cleanup function
+ * call_usermodehelper_setfns - set a cleanup/init function
* @info: a subprocess_info returned by call_usermodehelper_setup
* @cleanup: a cleanup function
+ * @init: an init function
+ * @data: arbitrary context sensitive data
+ *
+ * The init function is used to customize the helper process prior to
+ * exec. A non-zero return code causes the process to error out, exit,
+ * and return the failure to the calling process
*
- * The cleanup function is just befor ethe subprocess_info is about to
+ * The cleanup function is just before ethe subprocess_info is about to
* be freed. This can be used for freeing the argv and envp. The
* Function must be runnable in either a process context or the
* context in which call_usermodehelper_exec is called.
*/
-void call_usermodehelper_setcleanup(struct subprocess_info *info,
- void (*cleanup)(char **argv, char **envp))
+void call_usermodehelper_setfns(struct subprocess_info *info,
+ int (*init)(struct subprocess_info *info),
+ void (*cleanup)(struct subprocess_info *info),
+ void *data)
{
info->cleanup = cleanup;
+ info->init = init;
+ info->data = data;
}
-EXPORT_SYMBOL(call_usermodehelper_setcleanup);
+EXPORT_SYMBOL(call_usermodehelper_setfns);
/**
* call_usermodehelper_stdinpipe - set up a pipe to be used for stdin
@@ -515,7 +521,8 @@ int call_usermodehelper_pipe(char *path, char **argv, char **envp,
struct subprocess_info *sub_info;
int ret;
- sub_info = call_usermodehelper_setup(path, argv, envp, GFP_KERNEL);
+ sub_info = call_usermodehelper_setup(path, argv, envp,
+ GFP_KERNEL);
if (sub_info == NULL)
return -ENOMEM;
diff --git a/kernel/sys.c b/kernel/sys.c
index 0d36d889c74..e83ddbbaf89 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1632,9 +1632,9 @@ SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff";
-static void argv_cleanup(char **argv, char **envp)
+static void argv_cleanup(struct subprocess_info *info)
{
- argv_free(argv);
+ argv_free(info->argv);
}
/**
@@ -1668,7 +1668,7 @@ int orderly_poweroff(bool force)
goto out;
}
- call_usermodehelper_setcleanup(info, argv_cleanup);
+ call_usermodehelper_setfns(info, NULL, argv_cleanup, NULL);
ret = call_usermodehelper_exec(info, UMH_NO_WAIT);