android_kernel_xiaomi_sm8350/fs/afs/main.c
David Howells df44f9f4f9 AFS: Fix the module init error handling
Fix the module init error handling.  There are a bunch of goto labels for
aborting the init procedure at different points and just undoing what needs
undoing - they aren't all in the right places, however.

This can lead to an oops like the following:

	BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
	IP: [<ffffffff81042a31>] destroy_workqueue+0x17/0xc0
	...
	Modules linked in: kafs(+) dns_resolver rxkad af_rxrpc fscache

	Pid: 2171, comm: insmod Not tainted 2.6.35-cachefs+ #319 DG965RY/
	...
	Process insmod (pid: 2171, threadinfo ffff88003ca6a000, task ffff88003dcc3050)
	...
	Call Trace:
	 [<ffffffffa0055994>] afs_callback_update_kill+0x10/0x12 [kafs]
	 [<ffffffffa007d1c5>] afs_init+0x190/0x1ce [kafs]
	 [<ffffffffa007d035>] ? afs_init+0x0/0x1ce [kafs]
	 [<ffffffff810001ef>] do_one_initcall+0x59/0x14e
	 [<ffffffff8105f7ee>] sys_init_module+0x9c/0x1de
	 [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-07 14:23:37 -07:00

176 lines
4.2 KiB
C

/* AFS client file system
*
* Copyright (C) 2002,5 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/completion.h>
#include <linux/sched.h>
#include "internal.h"
MODULE_DESCRIPTION("AFS Client File System");
MODULE_AUTHOR("Red Hat, Inc.");
MODULE_LICENSE("GPL");
unsigned afs_debug;
module_param_named(debug, afs_debug, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(debug, "AFS debugging mask");
static char *rootcell;
module_param(rootcell, charp, 0);
MODULE_PARM_DESC(rootcell, "root AFS cell name and VL server IP addr list");
struct afs_uuid afs_uuid;
/*
* get a client UUID
*/
static int __init afs_get_client_UUID(void)
{
struct timespec ts;
u64 uuidtime;
u16 clockseq;
int ret;
/* read the MAC address of one of the external interfaces and construct
* a UUID from it */
ret = afs_get_MAC_address(afs_uuid.node, sizeof(afs_uuid.node));
if (ret < 0)
return ret;
getnstimeofday(&ts);
uuidtime = (u64) ts.tv_sec * 1000 * 1000 * 10;
uuidtime += ts.tv_nsec / 100;
uuidtime += AFS_UUID_TO_UNIX_TIME;
afs_uuid.time_low = uuidtime;
afs_uuid.time_mid = uuidtime >> 32;
afs_uuid.time_hi_and_version = (uuidtime >> 48) & AFS_UUID_TIMEHI_MASK;
afs_uuid.time_hi_and_version = AFS_UUID_VERSION_TIME;
get_random_bytes(&clockseq, 2);
afs_uuid.clock_seq_low = clockseq;
afs_uuid.clock_seq_hi_and_reserved =
(clockseq >> 8) & AFS_UUID_CLOCKHI_MASK;
afs_uuid.clock_seq_hi_and_reserved = AFS_UUID_VARIANT_STD;
_debug("AFS UUID: %08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
afs_uuid.time_low,
afs_uuid.time_mid,
afs_uuid.time_hi_and_version,
afs_uuid.clock_seq_hi_and_reserved,
afs_uuid.clock_seq_low,
afs_uuid.node[0], afs_uuid.node[1], afs_uuid.node[2],
afs_uuid.node[3], afs_uuid.node[4], afs_uuid.node[5]);
return 0;
}
/*
* initialise the AFS client FS module
*/
static int __init afs_init(void)
{
int ret;
printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 registering.\n");
ret = afs_get_client_UUID();
if (ret < 0)
return ret;
/* register the /proc stuff */
ret = afs_proc_init();
if (ret < 0)
return ret;
#ifdef CONFIG_AFS_FSCACHE
/* we want to be able to cache */
ret = fscache_register_netfs(&afs_cache_netfs);
if (ret < 0)
goto error_cache;
#endif
/* initialise the cell DB */
ret = afs_cell_init(rootcell);
if (ret < 0)
goto error_cell_init;
/* initialise the VL update process */
ret = afs_vlocation_update_init();
if (ret < 0)
goto error_vl_update_init;
/* initialise the callback update process */
ret = afs_callback_update_init();
if (ret < 0)
goto error_callback_update_init;
/* create the RxRPC transport */
ret = afs_open_socket();
if (ret < 0)
goto error_open_socket;
/* register the filesystems */
ret = afs_fs_init();
if (ret < 0)
goto error_fs;
return ret;
error_fs:
afs_close_socket();
error_open_socket:
afs_callback_update_kill();
error_callback_update_init:
afs_vlocation_purge();
error_vl_update_init:
afs_cell_purge();
error_cell_init:
#ifdef CONFIG_AFS_FSCACHE
fscache_unregister_netfs(&afs_cache_netfs);
error_cache:
#endif
afs_proc_cleanup();
rcu_barrier();
printk(KERN_ERR "kAFS: failed to register: %d\n", ret);
return ret;
}
/* XXX late_initcall is kludgy, but the only alternative seems to create
* a transport upon the first mount, which is worse. Or is it?
*/
late_initcall(afs_init); /* must be called after net/ to create socket */
/*
* clean up on module removal
*/
static void __exit afs_exit(void)
{
printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 unregistering.\n");
afs_fs_exit();
afs_kill_lock_manager();
afs_close_socket();
afs_purge_servers();
afs_callback_update_kill();
afs_vlocation_purge();
flush_scheduled_work();
afs_cell_purge();
#ifdef CONFIG_AFS_FSCACHE
fscache_unregister_netfs(&afs_cache_netfs);
#endif
afs_proc_cleanup();
rcu_barrier();
}
module_exit(afs_exit);