diff options
| -rw-r--r-- | include/linux/kmod.h | 4 | ||||
| -rw-r--r-- | kernel/kmod.c | 55 |
2 files changed, 58 insertions, 1 deletions
diff --git a/include/linux/kmod.h b/include/linux/kmod.h index 0db22a1ab47..10f505c8431 100644 --- a/include/linux/kmod.h +++ b/include/linux/kmod.h @@ -47,4 +47,8 @@ call_usermodehelper(char *path, char **argv, char **envp, int wait) extern void usermodehelper_init(void); +struct file; +extern int call_usermodehelper_pipe(char *path, char *argv[], char *envp[], + struct file **filp); + #endif /* __LINUX_KMOD_H__ */ diff --git a/kernel/kmod.c b/kernel/kmod.c index 842f8015d7f..5c63c53014a 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -122,6 +122,7 @@ struct subprocess_info { struct key *ring; int wait; int retval; + struct file *stdin; }; /* @@ -145,12 +146,26 @@ static int ____call_usermodehelper(void *data) key_put(old_session); + /* Install input pipe when needed */ + if (sub_info->stdin) { + struct files_struct *f = current->files; + struct fdtable *fdt; + /* no races because files should be private here */ + sys_close(0); + fd_install(0, sub_info->stdin); + spin_lock(&f->file_lock); + fdt = files_fdtable(f); + FD_SET(0, fdt->open_fds); + FD_CLR(0, fdt->close_on_exec); + spin_unlock(&f->file_lock); + } + /* We can run anywhere, unlike our parent keventd(). */ set_cpus_allowed(current, CPU_MASK_ALL); retval = -EPERM; if (current->fs->root) - retval = execve(sub_info->path, sub_info->argv,sub_info->envp); + retval = execve(sub_info->path, sub_info->argv, sub_info->envp); /* Exec failed? */ sub_info->retval = retval; @@ -268,6 +283,44 @@ int call_usermodehelper_keys(char *path, char **argv, char **envp, } EXPORT_SYMBOL(call_usermodehelper_keys); +int call_usermodehelper_pipe(char *path, char **argv, char **envp, + struct file **filp) +{ + DECLARE_COMPLETION(done); + struct subprocess_info sub_info = { + .complete = &done, + .path = path, + .argv = argv, + .envp = envp, + .retval = 0, + }; + struct file *f; + DECLARE_WORK(work, __call_usermodehelper, &sub_info); + + if (!khelper_wq) + return -EBUSY; + + if (path[0] == '\0') + return 0; + + f = create_write_pipe(); + if (!f) + return -ENOMEM; + *filp = f; + + f = create_read_pipe(f); + if (!f) { + free_write_pipe(*filp); + return -ENOMEM; + } + sub_info.stdin = f; + + queue_work(khelper_wq, &work); + wait_for_completion(&done); + return sub_info.retval; +} +EXPORT_SYMBOL(call_usermodehelper_pipe); + void __init usermodehelper_init(void) { khelper_wq = create_singlethread_workqueue("khelper"); |