This is a note to let you know that I've just added the patch titled
ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE
to the 4.14-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:
ptr_ring-fail-early-if-queue-occupies-more-than-kmalloc_max_size.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 6e6e41c3112276288ccaf80c70916779b84bb276 Mon Sep 17 00:00:00 2001
From: Jason Wang <jasowang@xxxxxxxxxx>
Date: Fri, 9 Feb 2018 17:45:49 +0800
Subject: ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE
From: Jason Wang <jasowang@xxxxxxxxxx>
commit 6e6e41c3112276288ccaf80c70916779b84bb276 upstream.
To avoid slab to warn about exceeded size, fail early if queue
occupies more than KMALLOC_MAX_SIZE.
Reported-by: syzbot+e4d4f9ddd4295539735d@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 2e0ab8ca83c12 ("ptr_ring: array based FIFO for pointers")
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/linux/ptr_ring.h | 2 ++
1 file changed, 2 insertions(+)
--- a/include/linux/ptr_ring.h
+++ b/include/linux/ptr_ring.h
@@ -447,6 +447,8 @@ static inline int ptr_ring_consume_batch
static inline void **__ptr_ring_init_queue_alloc(unsigned int size, gfp_t gfp)
{
+ if (size * sizeof(void *) > KMALLOC_MAX_SIZE)
+ return NULL;
return kcalloc(size, sizeof(void *), gfp);
}
Patches currently in stable-queue which might be from jasowang@xxxxxxxxxx are
queue-4.14/ptr_ring-try-vmalloc-when-kmalloc-fails.patch
queue-4.14/vhost-use-mutex_lock_nested-in-vhost_dev_lock_vqs.patch
queue-4.14/ptr_ring-fail-early-if-queue-occupies-more-than-kmalloc_max_size.patch