From: Michel Lespinasse <walken@google.com>
Date: Fri, 16 Dec 2011 04:49:25 +0000 (+1100)
Subject: binary_sysctl(): fix memory leak
X-Git-Tag: next-20111219~1^2~245
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=43b2c7822c19c4454f6265aa2ffec6fb92a9c82a;p=karo-tx-linux.git

binary_sysctl(): fix memory leak

binary_sysctl() calls sysctl_getname() which allocates from names_cache
slab usin __getname()

The matching function to free the name is __putname(), and not putname()
which should be used only to match getname() allocations.

This is because when auditing is enabled, putname() calls audit_putname
*instead* (not in addition) to __putname().  Then, if a syscall is in
progress, audit_putname does not release the name - instead, it expects
the name to get released when the syscall completes, but that will happen
only if audit_getname() was called previously, i.e.  if the name was
allocated with getname() rather than the naked __getname().  So,
__getname() followed by putname() ends up leaking memory.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index 6318b511afa1..a650694883a1 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -1354,7 +1354,7 @@ static ssize_t binary_sysctl(const int *name, int nlen,
 
 	fput(file);
 out_putname:
-	putname(pathname);
+	__putname(pathname);
 out:
 	return result;
 }