On 14/02/28, Eric W. Biederman wrote:
 
 In perverse cases of file descriptor passing the current network
 namespace of a process and the network namespace of a socket used by
 that socket may differ.  Therefore use the network namespace of the
 appropiate socket to ensure replies always go to the appropiate
 socket.
 
 Signed-off-by: "Eric W. Biederman" <ebiederm(a)xmission.com> 
Signed-off-by: Richard Guy Briggs <rgb(a)tricolour.ca>
 ---
 
 This is an incremental change on top of my previous patch to guarantee
 that replies always happen in the appropriate network namespace.
 
  include/linux/audit.h |    3 ++-
  kernel/audit.c        |   21 ++++++++++-----------
  kernel/auditfilter.c  |    7 +++++--
  3 files changed, 17 insertions(+), 14 deletions(-)
 
 diff --git a/include/linux/audit.h b/include/linux/audit.h
 index aa865a9a4c4f..ec1464df4c60 100644
 --- a/include/linux/audit.h
 +++ b/include/linux/audit.h
 @@ -43,6 +43,7 @@ struct mq_attr;
  struct mqstat;
  struct audit_watch;
  struct audit_tree;
 +struct sk_buff;
  
  struct audit_krule {
  	int			vers_ops;
 @@ -463,7 +464,7 @@ extern int audit_filter_user(int type);
  extern int audit_filter_type(int type);
  extern int audit_rule_change(int type, __u32 portid, int seq,
  				void *data, size_t datasz);
 -extern int audit_list_rules_send(__u32 portid, int seq);
 +extern int audit_list_rules_send(struct sk_buff *request_skb, int seq);
  
  extern u32 audit_enabled;
  #else /* CONFIG_AUDIT */
 diff --git a/kernel/audit.c b/kernel/audit.c
 index 1e5756f16f6f..32086bff5564 100644
 --- a/kernel/audit.c
 +++ b/kernel/audit.c
 @@ -570,9 +570,11 @@ static int audit_send_reply_thread(void *arg)
   * Allocates an skb, builds the netlink message, and sends it to the port id.
   * No failure notifications.
   */
 -static void audit_send_reply(__u32 portid, int seq, int type, int done,
 +static void audit_send_reply(struct sk_buff *request_skb, int seq, int type, int done,
  			     int multi, const void *payload, int size)
  {
 +	u32 portid = NETLINK_CB(request_skb).portid;
 +	struct net *net = sock_net(NETLINK_CB(request_skb).sk);
  	struct sk_buff *skb;
  	struct task_struct *tsk;
  	struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
 @@ -585,7 +587,7 @@ static void audit_send_reply(__u32 portid, int seq, int type, int
done,
  	if (!skb)
  		goto out;
  
 -	reply->net = get_net(current->nsproxy->net_ns);
 +	reply->net = get_net(net);
  	reply->portid = portid;
  	reply->skb = skb;
  
 @@ -675,8 +677,7 @@ static int audit_get_feature(struct sk_buff *skb)
  
  	seq = nlmsg_hdr(skb)->nlmsg_seq;
  
 -	audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0,
 -			 &af, sizeof(af));
 +	audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &af, sizeof(af));
  
  	return 0;
  }
 @@ -796,8 +797,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr
*nlh)
  		s.backlog		= skb_queue_len(&audit_skb_queue);
  		s.version		= AUDIT_VERSION_LATEST;
  		s.backlog_wait_time	= audit_backlog_wait_time;
 -		audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0,
 -				 &s, sizeof(s));
 +		audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &s, sizeof(s));
  		break;
  	}
  	case AUDIT_SET: {
 @@ -907,7 +907,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr
*nlh)
  					   seq, data, nlmsg_len(nlh));
  		break;
  	case AUDIT_LIST_RULES:
 -		err = audit_list_rules_send(NETLINK_CB(skb).portid, seq);
 +		err = audit_list_rules_send(skb, seq);
  		break;
  	case AUDIT_TRIM:
  		audit_trim_trees();
 @@ -972,8 +972,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr
*nlh)
  			memcpy(sig_data->ctx, ctx, len);
  			security_release_secctx(ctx, len);
  		}
 -		audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_SIGNAL_INFO,
 -				0, 0, sig_data, sizeof(*sig_data) + len);
 +		audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
 +				 sig_data, sizeof(*sig_data) + len);
  		kfree(sig_data);
  		break;
  	case AUDIT_TTY_GET: {
 @@ -985,8 +985,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr
*nlh)
  		s.log_passwd = tsk->signal->audit_tty_log_passwd;
  		spin_unlock(&tsk->sighand->siglock);
  
 -		audit_send_reply(NETLINK_CB(skb).portid, seq,
 -				 AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
 +		audit_send_reply(skb, seq, AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
  		break;
  	}
  	case AUDIT_TTY_SET: {
 diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
 index a5e3d73d73e4..e8d1c7c515d7 100644
 --- a/kernel/auditfilter.c
 +++ b/kernel/auditfilter.c
 @@ -30,6 +30,7 @@
  #include <linux/slab.h>
  #include <linux/security.h>
  #include <net/net_namespace.h>
 +#include <net/sock.h>
  #include "audit.h"
  
  /*
 @@ -1069,8 +1070,10 @@ int audit_rule_change(int type, __u32 portid, int seq, void
*data,
   * @portid: target portid for netlink audit messages
   * @seq: netlink audit message sequence (serial) number
   */
 -int audit_list_rules_send(__u32 portid, int seq)
 +int audit_list_rules_send(struct sk_buff *request_skb, int seq)
  {
 +	u32 portid = NETLINK_CB(request_skb).portid;
 +	struct net *net = sock_net(NETLINK_CB(request_skb).sk);
  	struct task_struct *tsk;
  	struct audit_netlink_list *dest;
  	int err = 0;
 @@ -1084,7 +1087,7 @@ int audit_list_rules_send(__u32 portid, int seq)
  	dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL);
  	if (!dest)
  		return -ENOMEM;
 -	dest->net = get_net(current->nsproxy->net_ns);
 +	dest->net = get_net(net);
  	dest->portid = portid;
  	skb_queue_head_init(&dest->q);
  
 -- 
 1.7.5.4
  
- RGB
--
Richard Guy Briggs <rbriggs(a)redhat.com>
Senior Software Engineer, Kernel Security, AMER ENG Base Operating Systems, Red Hat
Remote, Ottawa, Canada
Voice: +1.647.777.2635, Internal: (81) 32635, Alt: +1.613.693.0684x3545