umd: Rename umd_info.cmdline umd_info.driver_name
authorEric W. Biederman <ebiederm@xmission.com>
Thu, 25 Jun 2020 16:38:08 +0000 (11:38 -0500)
committerEric W. Biederman <ebiederm@xmission.com>
Sat, 4 Jul 2020 14:35:13 +0000 (09:35 -0500)
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>
include/linux/usermode_driver.h
kernel/usermode_driver.c
net/ipv4/bpfilter/sockopt.c

index 7131ea611bab87afe4400902c814b5175a0e9b85..48cf25e3145d8bf9a3f7405ae4b7c1baae8320cb 100644 (file)
@@ -18,7 +18,7 @@ static inline void exit_umh(struct task_struct *tsk)
 #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;
index e73550e946d6aa194479fc51b868fb2f61fc55b1..46d60d855e93f3303c79e780bbc1795c2febdf8d 100644 (file)
@@ -67,9 +67,6 @@ static void umd_cleanup(struct subprocess_info *info)
  * @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 subprocess_info *info)
  */
 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_t len, struct umd_info *info)
        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_t len, struct umd_info *info)
        }
 
        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;
index c0dbcc86fcdb54cb1385e3fa8dcff77a5a6af44d..5050de28333d1fc0354913a3ed5b8dfa247614ca 100644 (file)
@@ -70,7 +70,7 @@ static int __init bpfilter_sockopt_init(void)
 {
        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;