proc: proc_get_inode() should get module only once
authorDenis V. Lunev <den@openvz.org>
Fri, 23 May 2008 20:04:47 +0000 (13:04 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sat, 24 May 2008 16:56:11 +0000 (09:56 -0700)
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

index 6f4e8dc97da1f24f6313b4425efa323fe82a644c..b08d10017911f43927646943307e26238e4fe7dc 100644 (file)
@@ -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: