From c4185a0e019387f5ad6e99009804965531fa1fab Mon Sep 17 00:00:00 2001
From: "Denis V. Lunev" <den@openvz.org>
Date: Fri, 23 May 2008 13:04:47 -0700
Subject: proc: proc_get_inode() should get module only once

Any file under /proc/net opened more than once leaked the refcounter
on the module it belongs to.

The problem is that module_get is called for each file opening while
module_put is called only when /proc inode is destroyed. So, lets put
module counter if we are dealing with already initialised inode.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=10737

Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: David Miller <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Robert Olsson <robert.olsson@its.uu.se>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Reported-by: Roland Kletzing <devzero@web.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 fs/proc/inode.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'fs/proc/inode.c')

diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 6f4e8dc97da1..b08d10017911 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -425,7 +425,8 @@ struct inode *proc_get_inode(struct super_block *sb, unsigned int ino,
 			}
 		}
 		unlock_new_inode(inode);
-	}
+	} else
+	       module_put(de->owner);
 	return inode;
 
 out_ino:
-- 
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