From aaf68cfbf2241d24d46583423f6bff5c47e088b3 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Thu, 8 Feb 2007 14:20:30 -0800 Subject: [PATCH] knfsd: fix a race in closing NFSd connections If you lose this race, it can iput a socket inode twice and you get a BUG in fs/inode.c When I added the option for user-space to close a socket, I added some cruft to svc_delete_socket so that I could call that function when closing a socket per user-space request. This was the wrong thing to do. I should have just set SK_CLOSE and let normal mechanisms do the work. Not only wrong, but buggy. The locking is all wrong and it openned up a race where-by a socket could be closed twice. So this patch: Introduces svc_close_socket which sets SK_CLOSE then either leave the close up to a thread, or calls svc_delete_socket if it can get SK_BUSY. Adds a bias to sk_busy which is removed when SK_DEAD is set, This avoid races around shutting down the socket. Changes several 'spin_lock' to 'spin_lock_bh' where the _bh was missing. Bugzilla-url: http://bugzilla.kernel.org/show_bug.cgi?id=7916 Signed-off-by: Neil Brown Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sunrpc/svcsock.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/sunrpc') diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h index 98b21ad370fd..db312a1e2eeb 100644 --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -63,7 +63,7 @@ struct svc_sock { * Function prototypes. */ int svc_makesock(struct svc_serv *, int, unsigned short); -void svc_delete_socket(struct svc_sock *); +void svc_close_socket(struct svc_sock *); int svc_recv(struct svc_rqst *, long); int svc_send(struct svc_rqst *); void svc_drop(struct svc_rqst *); -- cgit v1.2.3