diff options
Diffstat (limited to 'arch/um/drivers/mconsole_kern.c')
| -rw-r--r-- | arch/um/drivers/mconsole_kern.c | 62 |
1 files changed, 44 insertions, 18 deletions
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index ff3ab72fd90f..ff4bda95b9c7 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -1,7 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) * Copyright (C) 2001 - 2008 Jeff Dike (jdike@{addtoit,linux.intel}.com) - * Licensed under the GPL */ #include <linux/console.h> @@ -12,6 +12,7 @@ #include <linux/mm.h> #include <linux/module.h> #include <linux/notifier.h> +#include <linux/panic_notifier.h> #include <linux/reboot.h> #include <linux/sched/debug.h> #include <linux/proc_fs.h> @@ -36,6 +37,8 @@ #include "mconsole_kern.h" #include <os.h> +static struct vfsmount *proc_mnt = NULL; + static int do_unlink_socket(struct notifier_block *notifier, unsigned long what, void *data) { @@ -123,7 +126,7 @@ void mconsole_log(struct mc_request *req) void mconsole_proc(struct mc_request *req) { - struct vfsmount *mnt = task_active_pid_ns(current)->proc_mnt; + struct vfsmount *mnt = proc_mnt; char *buf; int len; struct file *file; @@ -134,7 +137,11 @@ void mconsole_proc(struct mc_request *req) ptr += strlen("proc"); ptr = skip_spaces(ptr); - file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY, 0); + if (!mnt) { + mconsole_reply(req, "Proc not available", 1, 0); + goto out; + } + file = file_open_root_mnt(mnt, ptr, O_RDONLY, 0); if (IS_ERR(file)) { mconsole_reply(req, "Failed to open file", 1, 0); printk(KERN_ERR "open /proc/%s: %ld\n", ptr, PTR_ERR(file)); @@ -217,7 +224,7 @@ void mconsole_go(struct mc_request *req) void mconsole_stop(struct mc_request *req) { - deactivate_fd(req->originating_fd, MCONSOLE_IRQ); + block_signals(); os_set_fd_block(req->originating_fd, 1); mconsole_reply(req, "stopped", 0, 0); for (;;) { @@ -240,6 +247,7 @@ void mconsole_stop(struct mc_request *req) } os_set_fd_block(req->originating_fd, 0); mconsole_reply(req, "", 0, 0); + unblock_signals(); } static DEFINE_SPINLOCK(mc_devices_lock); @@ -275,7 +283,7 @@ struct unplugged_pages { }; static DEFINE_MUTEX(plug_mem_mutex); -static unsigned long long unplugged_pages_count = 0; +static unsigned long long unplugged_pages_count; static LIST_HEAD(unplugged_pages); static int unplug_index = UNPLUGGED_PER_PAGE; @@ -546,7 +554,7 @@ struct mconsole_output { static DEFINE_SPINLOCK(client_lock); static LIST_HEAD(clients); -static char console_buf[MCONSOLE_MAX_DATA]; +static char console_buf[MCONSOLE_MAX_DATA] __nonstring; static void console_write(struct console *console, const char *string, unsigned int len) @@ -559,7 +567,7 @@ static void console_write(struct console *console, const char *string, while (len > 0) { n = min((size_t) len, ARRAY_SIZE(console_buf)); - strncpy(console_buf, string, n); + memcpy(console_buf, string, n); string += n; len -= n; @@ -642,7 +650,7 @@ static void stack_proc(void *arg) { struct task_struct *task = arg; - show_stack(task, NULL); + show_stack(task, NULL, KERN_INFO); } /* @@ -683,6 +691,24 @@ void mconsole_stack(struct mc_request *req) with_console(req, stack_proc, to); } +static int __init mount_proc(void) +{ + struct file_system_type *proc_fs_type; + struct vfsmount *mnt; + + proc_fs_type = get_fs_type("proc"); + if (!proc_fs_type) + return -ENODEV; + + mnt = kern_mount(proc_fs_type); + put_filesystem(proc_fs_type); + if (IS_ERR(mnt)) + return PTR_ERR(mnt); + + proc_mnt = mnt; + return 0; +} + /* * Changed by mconsole_setup, which is __setup, and called before SMP is * active. @@ -696,6 +722,8 @@ static int __init mconsole_init(void) int err; char file[UNIX_PATH_MAX]; + mount_proc(); + if (umid_file_name("mconsole", file, sizeof(file))) return -1; snprintf(mconsole_socket_name, sizeof(file), "%s", file); @@ -712,7 +740,7 @@ static int __init mconsole_init(void) err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt, IRQF_SHARED, "mconsole", (void *)sock); - if (err) { + if (err < 0) { printk(KERN_ERR "Failed to get IRQ for management console\n"); goto out; } @@ -752,10 +780,9 @@ static ssize_t mconsole_proc_write(struct file *file, return count; } -static const struct file_operations mconsole_proc_fops = { - .owner = THIS_MODULE, - .write = mconsole_proc_write, - .llseek = noop_llseek, +static const struct proc_ops mconsole_proc_ops = { + .proc_write = mconsole_proc_write, + .proc_lseek = noop_llseek, }; static int create_proc_mconsole(void) @@ -765,7 +792,7 @@ static int create_proc_mconsole(void) if (notify_socket == NULL) return 0; - ent = proc_create("mconsole", 0200, NULL, &mconsole_proc_fops); + ent = proc_create("mconsole", 0200, NULL, &mconsole_proc_ops); if (ent == NULL) { printk(KERN_INFO "create_proc_mconsole : proc_create failed\n"); return 0; @@ -819,13 +846,12 @@ static int notify_panic(struct notifier_block *self, unsigned long unused1, mconsole_notify(notify_socket, MCONSOLE_PANIC, message, strlen(message) + 1); - return 0; + return NOTIFY_DONE; } static struct notifier_block panic_exit_notifier = { - .notifier_call = notify_panic, - .next = NULL, - .priority = 1 + .notifier_call = notify_panic, + .priority = INT_MAX, /* run as soon as possible */ }; static int add_notifier(void) |