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

    mm, slab: initialize object alignment on cache creation

to the 3.14-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:
     mm-slab-initialize-object-alignment-on-cache-creation.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From d4a5fca592b9ab52b90bb261a90af3c8f53be011 Mon Sep 17 00:00:00 2001
From: David Rientjes <[email protected]>
Date: Thu, 25 Sep 2014 16:05:20 -0700
Subject: mm, slab: initialize object alignment on cache creation

From: David Rientjes <[email protected]>

commit d4a5fca592b9ab52b90bb261a90af3c8f53be011 upstream.

Since commit 4590685546a3 ("mm/sl[aou]b: Common alignment code"), the
"ralign" automatic variable in __kmem_cache_create() may be used as
uninitialized.

The proper alignment defaults to BYTES_PER_WORD and can be overridden by
SLAB_RED_ZONE or the alignment specified by the caller.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=85031

Signed-off-by: David Rientjes <[email protected]>
Reported-by: Andrei Elovikov <[email protected]>
Acked-by: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 mm/slab.c |   11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2189,7 +2189,8 @@ static int __init_refok setup_cpu_cache(
 int
 __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
 {
-       size_t left_over, freelist_size, ralign;
+       size_t left_over, freelist_size;
+       size_t ralign = BYTES_PER_WORD;
        gfp_t gfp;
        int err;
        size_t size = cachep->size;
@@ -2222,14 +2223,6 @@ __kmem_cache_create (struct kmem_cache *
                size &= ~(BYTES_PER_WORD - 1);
        }
 
-       /*
-        * Redzoning and user store require word alignment or possibly larger.
-        * Note this will be overridden by architecture or caller mandated
-        * alignment if either is greater than BYTES_PER_WORD.
-        */
-       if (flags & SLAB_STORE_USER)
-               ralign = BYTES_PER_WORD;
-
        if (flags & SLAB_RED_ZONE) {
                ralign = REDZONE_ALIGN;
                /* If redzoning, ensure that the second redzone is suitably


Patches currently in stable-queue which might be from [email protected] are

queue-3.14/mm-slab-initialize-object-alignment-on-cache-creation.patch
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