Re: [PATCH] NFS: hard-code init_net for NFS callback transports

["J. Bruce Fields" <bfields@fieldses.org>]

On Fri, Jun 01, 2012 at 01:55:47PM +0400, Stanislav Kinsbursky wrote:
> This patch set is a bug fix for Bruce's 3.5 branch.
> I'll rebase this for 3.4 and resend.

Apologies for neglecting this, I'm done with the bakeathon and should be
back to this soon.

But, I'm a bit confused: you say you'll rebase this, but I've only seen
two rebased patches for 3.4, and neither looks like a simple rebase of
this one.

OK, I'll look more closely and probably I'll figure out.  But in
general, a little more detail in changelogs would help me process
patches more quickly:

	- Please make sure it's clear whether a given patch is a bug
	  fix, a new feature, or code reshuffling that isn't intended to
	  change behavior.  If it's a bug fix, tell me whether we've had
	  the bug forever or whether it's a recent regression.  And
	  (relevant here) if it's a recent regression, reference the ID
	  of the commit that introduced it.
	- If something is a backport, please reference in the changelog
	  the commit ID of the backported patch, especially if it's not
	  obviously the same.

--b.
	

> 
> In case of destroying mount namespace on child reaper exit, nsproxy is zeroed
> to the point already. So, dereferencing of it is invalid.
> This patch hard-code "init_net" for all network namespace references for NFS
> callback services. This will be fixed with proper NFS callback
> containerization.
> 
> Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
> ---
>  fs/nfs/callback.c |   11 +++++------
>  1 files changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
> index 970659d..23ff18f 100644
> --- a/fs/nfs/callback.c
> +++ b/fs/nfs/callback.c
> @@ -17,7 +17,6 @@
>  #include <linux/kthread.h>
>  #include <linux/sunrpc/svcauth_gss.h>
>  #include <linux/sunrpc/bc_xprt.h>
> -#include <linux/nsproxy.h>
>  
>  #include <net/inet_sock.h>
>  
> @@ -107,7 +106,7 @@ nfs4_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
>  {
>  	int ret;
>  
> -	ret = svc_create_xprt(serv, "tcp", xprt->xprt_net, PF_INET,
> +	ret = svc_create_xprt(serv, "tcp", &init_net, PF_INET,
>  				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
>  	if (ret <= 0)
>  		goto out_err;
> @@ -115,7 +114,7 @@ nfs4_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
>  	dprintk("NFS: Callback listener port = %u (af %u)\n",
>  			nfs_callback_tcpport, PF_INET);
>  
> -	ret = svc_create_xprt(serv, "tcp", xprt->xprt_net, PF_INET6,
> +	ret = svc_create_xprt(serv, "tcp", &init_net, PF_INET6,
>  				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
>  	if (ret > 0) {
>  		nfs_callback_tcpport6 = ret;
> @@ -184,7 +183,7 @@ nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
>  	 * fore channel connection.
>  	 * Returns the input port (0) and sets the svc_serv bc_xprt on success
>  	 */
> -	ret = svc_create_xprt(serv, "tcp-bc", xprt->xprt_net, PF_INET, 0,
> +	ret = svc_create_xprt(serv, "tcp-bc", &init_net, PF_INET, 0,
>  			      SVC_SOCK_ANONYMOUS);
>  	if (ret < 0) {
>  		rqstp = ERR_PTR(ret);
> @@ -254,7 +253,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
>  	char svc_name[12];
>  	int ret = 0;
>  	int minorversion_setup;
> -	struct net *net = current->nsproxy->net_ns;
> +	struct net *net = &init_net;
>  
>  	mutex_lock(&nfs_callback_mutex);
>  	if (cb_info->users++ || cb_info->task != NULL) {
> @@ -330,7 +329,7 @@ void nfs_callback_down(int minorversion)
>  	cb_info->users--;
>  	if (cb_info->users == 0 && cb_info->task != NULL) {
>  		kthread_stop(cb_info->task);
> -		svc_shutdown_net(cb_info->serv, current->nsproxy->net_ns);
> +		svc_shutdown_net(cb_info->serv, &init_net);
>  		svc_exit_thread(cb_info->rqst);
>  		cb_info->serv = NULL;
>  		cb_info->rqst = NULL;
>