netdev - [PATCH 3/7] SUNRPC: send notification events on pipefs sb creation and destruction

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20111028142542.5796.80283.stgit@localhost6.localdomain6>
Date:	Fri, 28 Oct 2011 18:25:43 +0300
From:	Stanislav Kinsbursky <skinsbursky@...allels.com>
To:	Trond.Myklebust@...app.com
Cc:	linux-nfs@...r.kernel.org, xemul@...allels.com, neilb@...e.de,
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
	bfields@...ldses.org, davem@...emloft.net, devel@...nvz.org
Subject: [PATCH 3/7] SUNRPC: send notification events on pipefs sb creation
	and destruction

They will be used to notify subscribers about pipefs superblock creation and
destruction.
Subcribers will have to create their dentries on passed superblock on mount
event and destroy otherwise.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@...allels.com>

---
 include/linux/sunrpc/rpc_pipe_fs.h |    8 ++++++++
 net/sunrpc/rpc_pipe.c              |   32 ++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 0 deletions(-)

diff --git a/include/linux/sunrpc/rpc_pipe_fs.h b/include/linux/sunrpc/rpc_pipe_fs.h
index cf14db9..c1cdb2f 100644
--- a/include/linux/sunrpc/rpc_pipe_fs.h
+++ b/include/linux/sunrpc/rpc_pipe_fs.h
@@ -44,6 +44,14 @@ RPC_I(struct inode *inode)
 	return container_of(inode, struct rpc_inode, vfs_inode);
 }
 
+extern int rpc_pipefs_notifier_register(struct notifier_block *);
+extern void rpc_pipefs_notifier_unregister(struct notifier_block *);
+
+enum {
+	RPC_PIPEFS_MOUNT,
+	RPC_PIPEFS_UMOUNT,
+};
+
 extern int rpc_queue_upcall(struct inode *, struct rpc_pipe_msg *);
 
 struct rpc_clnt;
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index a717564..8abeb9d 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -28,8 +28,10 @@
 #include <linux/sunrpc/rpc_pipe_fs.h>
 #include <linux/sunrpc/cache.h>
 #include <linux/nsproxy.h>
+#include <linux/notifier.h>
 
 #include "netns.h"
+#include "sunrpc.h"
 
 static struct vfsmount *rpc_mnt __read_mostly;
 static int rpc_mount_count;
@@ -41,6 +43,20 @@ static struct kmem_cache *rpc_inode_cachep __read_mostly;
 
 #define RPC_UPCALL_TIMEOUT (30*HZ)
 
+static BLOCKING_NOTIFIER_HEAD(rpc_pipefs_notifier_list);
+
+int rpc_pipefs_notifier_register(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_cond_register(&rpc_pipefs_notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_register);
+
+void rpc_pipefs_notifier_unregister(struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&rpc_pipefs_notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_unregister);
+
 static void rpc_purge_list(struct rpc_inode *rpci, struct list_head *head,
 		void (*destroy_msg)(struct rpc_pipe_msg *), int err)
 {
@@ -1010,6 +1026,7 @@ rpc_fill_super(struct super_block *sb, void *data, int silent)
 	struct inode *inode;
 	struct dentry *root;
 	struct net *net = data;
+	int err;
 
 	sb->s_blocksize = PAGE_CACHE_SIZE;
 	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
@@ -1027,8 +1044,20 @@ rpc_fill_super(struct super_block *sb, void *data, int silent)
 	}
 	if (rpc_populate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF, NULL))
 		return -ENOMEM;
+	err = blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
+					   RPC_PIPEFS_MOUNT,
+					   sb);
+	if (err)
+		goto err_depopulate;
 	sb->s_fs_info = get_net(net);
 	return 0;
+
+err_depopulate:
+	blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
+					   RPC_PIPEFS_UMOUNT,
+					   sb);
+	__rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
+	return err;
 }
 
 static struct dentry *
@@ -1043,6 +1072,9 @@ void rpc_kill_sb(struct super_block *sb)
 	struct net *net = sb->s_fs_info;
 
 	put_net(net);
+	blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
+					   RPC_PIPEFS_UMOUNT,
+					   sb);
 	kill_litter_super(sb);
 }
 

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html