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>
diff --git a/fs/afs/main.c b/fs/afs/main.c
index 66d54d3..cfd1cbe 100644
--- a/fs/afs/main.c
+++ b/fs/afs/main.c
@@ -111,6 +111,8 @@
/* 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();
@@ -127,15 +129,16 @@
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_callback_update_kill();
- afs_vlocation_purge();
- afs_cell_purge();
afs_proc_cleanup();
rcu_barrier();
printk(KERN_ERR "kAFS: failed to register: %d\n", ret);