From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Thu, 25 Jun 2020 11:38:08 -0500
Subject: umd: Rename umd_info.cmdline umd_info.driver_name
Patch-mainline: v5.9-rc1
Git-commit: 1199c6c3da5197e9924a906b9de71b8d0ac62a01
References: bsc#1177028

The only thing supplied in the cmdline today is the driver name so
rename the field to clarify the code.

As this value is always supplied stop trying to handle the case of
a NULL cmdline.

Additionally since we now have a name we can count on use the
driver_name any place where the code is looking for a name
of the binary.

v1: https://lkml.kernel.org/r/87imfef0k3.fsf_-_@x220.int.ebiederm.org
v2: https://lkml.kernel.org/r/87366d63os.fsf_-_@x220.int.ebiederm.org
Link: https://lkml.kernel.org/r/20200702164140.4468-7-ebiederm@xmission.com
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Gary Lin <glin@suse.com>
---
 include/linux/usermode_driver.h |    2 +-
 kernel/usermode_driver.c        |   11 ++++-------
 net/ipv4/bpfilter/sockopt.c     |    2 +-
 3 files changed, 6 insertions(+), 9 deletions(-)

--- a/include/linux/usermode_driver.h
+++ b/include/linux/usermode_driver.h
@@ -18,7 +18,7 @@ static inline void exit_umh(struct task_
 #endif
 
 struct umd_info {
-	const char *cmdline;
+	const char *driver_name;
 	struct file *pipe_to_umh;
 	struct file *pipe_from_umh;
 	struct list_head list;
--- a/kernel/usermode_driver.c
+++ b/kernel/usermode_driver.c
@@ -67,9 +67,6 @@ static void umd_cleanup(struct subproces
  * @len: length of the blob
  * @info: information about usermode process (shouldn't be NULL)
  *
- * If info->cmdline is set it will be used as command line for the
- * user process, else "usermodehelper" is used.
- *
  * Returns either negative error or zero which indicates success
  * in executing a blob of bytes as a usermode process. In such
  * case 'struct umd_info *info' is populated with two pipes
@@ -79,7 +76,6 @@ static void umd_cleanup(struct subproces
  */
 int fork_usermode_blob(void *data, size_t len, struct umd_info *info)
 {
-	const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper";
 	struct subprocess_info *sub_info;
 	char **argv = NULL;
 	struct file *file;
@@ -87,7 +83,7 @@ int fork_usermode_blob(void *data, size_
 	loff_t pos = 0;
 	int err;
 
-	file = shmem_kernel_file_setup("", len, 0);
+	file = shmem_kernel_file_setup(info->driver_name, len, 0);
 	if (IS_ERR(file))
 		return PTR_ERR(file);
 
@@ -100,11 +96,12 @@ int fork_usermode_blob(void *data, size_
 	}
 
 	err = -ENOMEM;
-	argv = argv_split(GFP_KERNEL, cmdline, NULL);
+	argv = argv_split(GFP_KERNEL, info->driver_name, NULL);
 	if (!argv)
 		goto out;
 
-	sub_info = call_usermodehelper_setup("none", argv, NULL, GFP_KERNEL,
+	sub_info = call_usermodehelper_setup(info->driver_name, argv, NULL,
+					     GFP_KERNEL,
 					     umd_setup, umd_cleanup, info);
 	if (!sub_info)
 		goto out;
--- a/net/ipv4/bpfilter/sockopt.c
+++ b/net/ipv4/bpfilter/sockopt.c
@@ -70,7 +70,7 @@ static int __init bpfilter_sockopt_init(
 {
 	mutex_init(&bpfilter_ops.lock);
 	bpfilter_ops.stop = true;
-	bpfilter_ops.info.cmdline = "bpfilter_umh";
+	bpfilter_ops.info.driver_name = "bpfilter_umh";
 	bpfilter_ops.info.cleanup = &bpfilter_umh_cleanup;
 
 	return 0;