From: "Dr. David Alan Gilbert" <linux@xxxxxxxxxxx> The last use of the usermode driver code was removed by commit 98e20e5e13d2 ("bpfilter: remove bpfilter") Remove the code. Signed-off-by: Dr. David Alan Gilbert <linux@xxxxxxxxxxx> --- include/linux/usermode_driver.h | 19 ---- kernel/Makefile | 1 - kernel/bpf/preload/Kconfig | 4 - kernel/usermode_driver.c | 191 -------------------------------- 4 files changed, 215 deletions(-) delete mode 100644 include/linux/usermode_driver.h delete mode 100644 kernel/usermode_driver.c diff --git a/include/linux/usermode_driver.h b/include/linux/usermode_driver.h deleted file mode 100644 index ad970416260d..000000000000 --- a/include/linux/usermode_driver.h +++ /dev/null @@ -1,19 +0,0 @@ -#ifndef __LINUX_USERMODE_DRIVER_H__ -#define __LINUX_USERMODE_DRIVER_H__ - -#include <linux/umh.h> -#include <linux/path.h> - -struct umd_info { - const char *driver_name; - struct file *pipe_to_umh; - struct file *pipe_from_umh; - struct path wd; - struct pid *tgid; -}; -int umd_load_blob(struct umd_info *info, const void *data, size_t len); -int umd_unload_blob(struct umd_info *info); -int fork_usermode_driver(struct umd_info *info); -void umd_cleanup_helper(struct umd_info *info); - -#endif /* __LINUX_USERMODE_DRIVER_H__ */ diff --git a/kernel/Makefile b/kernel/Makefile index 87866b037fbe..25d58da2a6ee 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -12,7 +12,6 @@ obj-y = fork.o exec_domain.o panic.o \ notifier.o ksysfs.o cred.o reboot.o \ async.o range.o smpboot.o ucount.o regset.o ksyms_common.o -obj-$(CONFIG_USERMODE_DRIVER) += usermode_driver.o obj-$(CONFIG_MULTIUSER) += groups.o obj-$(CONFIG_VHOST_TASK) += vhost_task.o diff --git a/kernel/bpf/preload/Kconfig b/kernel/bpf/preload/Kconfig index f9b11d01c3b5..aef7b0bc96d6 100644 --- a/kernel/bpf/preload/Kconfig +++ b/kernel/bpf/preload/Kconfig @@ -1,8 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only -config USERMODE_DRIVER - bool - default n - menuconfig BPF_PRELOAD bool "Preload BPF file system with kernel specific program and map iterators" depends on BPF diff --git a/kernel/usermode_driver.c b/kernel/usermode_driver.c deleted file mode 100644 index 8303f4c7ca71..000000000000 --- a/kernel/usermode_driver.c +++ /dev/null @@ -1,191 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * umd - User mode driver support - */ -#include <linux/shmem_fs.h> -#include <linux/pipe_fs_i.h> -#include <linux/mount.h> -#include <linux/fs_struct.h> -#include <linux/task_work.h> -#include <linux/usermode_driver.h> - -static struct vfsmount *blob_to_mnt(const void *data, size_t len, const char *name) -{ - struct file_system_type *type; - struct vfsmount *mnt; - struct file *file; - ssize_t written; - loff_t pos = 0; - - type = get_fs_type("tmpfs"); - if (!type) - return ERR_PTR(-ENODEV); - - mnt = kern_mount(type); - put_filesystem(type); - if (IS_ERR(mnt)) - return mnt; - - file = file_open_root_mnt(mnt, name, O_CREAT | O_WRONLY, 0700); - if (IS_ERR(file)) { - kern_unmount(mnt); - return ERR_CAST(file); - } - - written = kernel_write(file, data, len, &pos); - if (written != len) { - int err = written; - if (err >= 0) - err = -ENOMEM; - filp_close(file, NULL); - kern_unmount(mnt); - return ERR_PTR(err); - } - - fput(file); - - /* Flush delayed fput so exec can open the file read-only */ - flush_delayed_fput(); - task_work_run(); - return mnt; -} - -/** - * umd_load_blob - Remember a blob of bytes for fork_usermode_driver - * @info: information about usermode driver - * @data: a blob of bytes that can be executed as a file - * @len: The lentgh of the blob - * - */ -int umd_load_blob(struct umd_info *info, const void *data, size_t len) -{ - struct vfsmount *mnt; - - if (WARN_ON_ONCE(info->wd.dentry || info->wd.mnt)) - return -EBUSY; - - mnt = blob_to_mnt(data, len, info->driver_name); - if (IS_ERR(mnt)) - return PTR_ERR(mnt); - - info->wd.mnt = mnt; - info->wd.dentry = mnt->mnt_root; - return 0; -} -EXPORT_SYMBOL_GPL(umd_load_blob); - -/** - * umd_unload_blob - Disassociate @info from a previously loaded blob - * @info: information about usermode driver - * - */ -int umd_unload_blob(struct umd_info *info) -{ - if (WARN_ON_ONCE(!info->wd.mnt || - !info->wd.dentry || - info->wd.mnt->mnt_root != info->wd.dentry)) - return -EINVAL; - - kern_unmount(info->wd.mnt); - info->wd.mnt = NULL; - info->wd.dentry = NULL; - return 0; -} -EXPORT_SYMBOL_GPL(umd_unload_blob); - -static int umd_setup(struct subprocess_info *info, struct cred *new) -{ - struct umd_info *umd_info = info->data; - struct file *from_umh[2]; - struct file *to_umh[2]; - int err; - - /* create pipe to send data to umh */ - err = create_pipe_files(to_umh, 0); - if (err) - return err; - err = replace_fd(0, to_umh[0], 0); - fput(to_umh[0]); - if (err < 0) { - fput(to_umh[1]); - return err; - } - - /* create pipe to receive data from umh */ - err = create_pipe_files(from_umh, 0); - if (err) { - fput(to_umh[1]); - replace_fd(0, NULL, 0); - return err; - } - err = replace_fd(1, from_umh[1], 0); - fput(from_umh[1]); - if (err < 0) { - fput(to_umh[1]); - replace_fd(0, NULL, 0); - fput(from_umh[0]); - return err; - } - - set_fs_pwd(current->fs, &umd_info->wd); - umd_info->pipe_to_umh = to_umh[1]; - umd_info->pipe_from_umh = from_umh[0]; - umd_info->tgid = get_pid(task_tgid(current)); - return 0; -} - -static void umd_cleanup(struct subprocess_info *info) -{ - struct umd_info *umd_info = info->data; - - /* cleanup if umh_setup() was successful but exec failed */ - if (info->retval) - umd_cleanup_helper(umd_info); -} - -/** - * umd_cleanup_helper - release the resources which were allocated in umd_setup - * @info: information about usermode driver - */ -void umd_cleanup_helper(struct umd_info *info) -{ - fput(info->pipe_to_umh); - fput(info->pipe_from_umh); - put_pid(info->tgid); - info->tgid = NULL; -} -EXPORT_SYMBOL_GPL(umd_cleanup_helper); - -/** - * fork_usermode_driver - fork a usermode driver - * @info: information about usermode driver (shouldn't be NULL) - * - * Returns either negative error or zero which indicates success in - * executing a usermode driver. In such case 'struct umd_info *info' - * is populated with two pipes and a tgid of the process. The caller is - * responsible for health check of the user process, killing it via - * tgid, and closing the pipes when user process is no longer needed. - */ -int fork_usermode_driver(struct umd_info *info) -{ - struct subprocess_info *sub_info; - const char *argv[] = { info->driver_name, NULL }; - int err; - - if (WARN_ON_ONCE(info->tgid)) - return -EBUSY; - - err = -ENOMEM; - sub_info = call_usermodehelper_setup(info->driver_name, - (char **)argv, NULL, GFP_KERNEL, - umd_setup, umd_cleanup, info); - if (!sub_info) - goto out; - - err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC); -out: - return err; -} -EXPORT_SYMBOL_GPL(fork_usermode_driver); - - -- 2.47.0