Patch "kernel/ucount.c: mark user_header with kmemleak_ignore()" has been added to the 4.9-stable tree

Patch "kernel/ucount.c: mark user_header with kmemleak_ignore()" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    kernel/ucount.c: mark user_header with kmemleak_ignore()

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     kernel-ucount.c-mark-user_header-with-kmemleak_ignore.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Jun 15 11:38:13 CEST 2017
From: "Luis R. Rodriguez" <mcgrof@kernel.org>
Date: Tue, 23 May 2017 21:53:47 -0400
Subject: kernel/ucount.c: mark user_header with kmemleak_ignore()

From: "Luis R. Rodriguez" <mcgrof@kernel.org>


[ Upstream commit ed5bd7dc88edf4a4a9c67130742b1b59aa017a5f ]

The user_header gets caught by kmemleak with the following splat as
missing a free:

  unreferenced object 0xffff99667a733d80 (size 96):
  comm "swapper/0", pid 1, jiffies 4294892317 (age 62191.468s)
  hex dump (first 32 bytes):
    a0 b6 92 b4 ff ff ff ff 00 00 00 00 01 00 00 00  ................
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
     kmemleak_alloc+0x4a/0xa0
     __kmalloc+0x144/0x260
     __register_sysctl_table+0x54/0x5e0
     register_sysctl+0x1b/0x20
     user_namespace_sysctl_init+0x17/0x34
     do_one_initcall+0x52/0x1a0
     kernel_init_freeable+0x173/0x200
     kernel_init+0xe/0x100
     ret_from_fork+0x2c/0x40

The BUG_ON()s are intended to crash so no need to clean up after
ourselves on error there.  This is also a kernel/ subsys_init() we don't
need a respective exit call here as this is never modular, so just white
list it.

Link: http://lkml.kernel.org/r/20170203211404.31458-1-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 kernel/ucount.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/kernel/ucount.c
+++ b/kernel/ucount.c
@@ -231,11 +231,10 @@ static __init int user_namespace_sysctl_
 	 * properly.
 	 */
 	user_header = register_sysctl("user", empty);
+	kmemleak_ignore(user_header);
 	BUG_ON(!user_header);
 	BUG_ON(!setup_userns_sysctls(&init_user_ns));
 #endif
 	return 0;
 }
 subsys_initcall(user_namespace_sysctl_init);
-
-


Patches currently in stable-queue which might be from mcgrof@kernel.org are

queue-4.9/kernel-ucount.c-mark-user_header-with-kmemleak_ignore.patch