[PATCH v3 04/16] umh: Remove call_usermodehelper_setup_file.

From: Eric W. Biederman
Date: Thu Jul 02 2020 - 12:47:47 EST


The only caller of call_usermodehelper_setup_file is fork_usermode_blob.
In fork_usermode_blob replace call_usermodehelper_setup_file with
call_usermodehelper_setup and delete fork_usermodehelper_setup_file.

For this to work the argv_free is moved from umh_clean_and_save_pid
to fork_usermode_blob.

v1: https://lkml.kernel.org/r/87zh8qf0mp.fsf_-_@xxxxxxxxxxxxxxxxxxxxx
v2: https://lkml.kernel.org/r/87o8p163u1.fsf_-_@xxxxxxxxxxxxxxxxxxxxx
Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
---
include/linux/umh.h | 3 ---
kernel/umh.c | 42 +++++++++++-------------------------------
2 files changed, 11 insertions(+), 34 deletions(-)

diff --git a/include/linux/umh.h b/include/linux/umh.h
index aae16a0ebd0f..de08af00c68a 100644
--- a/include/linux/umh.h
+++ b/include/linux/umh.h
@@ -39,9 +39,6 @@ call_usermodehelper_setup(const char *path, char **argv, char **envp,
int (*init)(struct subprocess_info *info, struct cred *new),
void (*cleanup)(struct subprocess_info *), void *data);

-struct subprocess_info *call_usermodehelper_setup_file(struct file *file,
- int (*init)(struct subprocess_info *info, struct cred *new),
- void (*cleanup)(struct subprocess_info *), void *data);
struct umh_info {
const char *cmdline;
struct file *pipe_to_umh;
diff --git a/kernel/umh.c b/kernel/umh.c
index 26c3d493f168..b8fa9b99b366 100644
--- a/kernel/umh.c
+++ b/kernel/umh.c
@@ -402,33 +402,6 @@ struct subprocess_info *call_usermodehelper_setup(const char *path, char **argv,
}
EXPORT_SYMBOL(call_usermodehelper_setup);

-struct subprocess_info *call_usermodehelper_setup_file(struct file *file,
- int (*init)(struct subprocess_info *info, struct cred *new),
- void (*cleanup)(struct subprocess_info *info), void *data)
-{
- struct subprocess_info *sub_info;
- struct umh_info *info = data;
- const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper";
-
- sub_info = kzalloc(sizeof(struct subprocess_info), GFP_KERNEL);
- if (!sub_info)
- return NULL;
-
- sub_info->argv = argv_split(GFP_KERNEL, cmdline, NULL);
- if (!sub_info->argv) {
- kfree(sub_info);
- return NULL;
- }
-
- INIT_WORK(&sub_info->work, call_usermodehelper_exec_work);
- sub_info->path = "none";
- sub_info->file = file;
- sub_info->init = init;
- sub_info->cleanup = cleanup;
- sub_info->data = data;
- return sub_info;
-}
-
static int umd_setup(struct subprocess_info *info, struct cred *new)
{
struct umh_info *umh_info = info->data;
@@ -479,8 +452,6 @@ static void umd_cleanup(struct subprocess_info *info)
fput(umh_info->pipe_to_umh);
fput(umh_info->pipe_from_umh);
}
-
- argv_free(info->argv);
}

/**
@@ -501,7 +472,9 @@ static void umd_cleanup(struct subprocess_info *info)
*/
int fork_usermode_blob(void *data, size_t len, struct umh_info *info)
{
+ const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper";
struct subprocess_info *sub_info;
+ char **argv = NULL;
struct file *file;
ssize_t written;
loff_t pos = 0;
@@ -520,11 +493,16 @@ int fork_usermode_blob(void *data, size_t len, struct umh_info *info)
}

err = -ENOMEM;
- sub_info = call_usermodehelper_setup_file(file, umd_setup, umd_cleanup,
- info);
+ argv = argv_split(GFP_KERNEL, cmdline, NULL);
+ if (!argv)
+ goto out;
+
+ sub_info = call_usermodehelper_setup("none", argv, NULL, GFP_KERNEL,
+ umd_setup, umd_cleanup, info);
if (!sub_info)
goto out;

+ sub_info->file = file;
err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC);
if (!err) {
mutex_lock(&umh_list_lock);
@@ -532,6 +510,8 @@ int fork_usermode_blob(void *data, size_t len, struct umh_info *info)
mutex_unlock(&umh_list_lock);
}
out:
+ if (argv)
+ argv_free(argv);
fput(file);
return err;
}
--
2.25.0