Patch "relay: check array offset before using it" has been added to the 4.9-stable tree

Patch "relay: check array offset before using it" 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

    relay: check array offset before using it

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:
     relay-check-array-offset-before-using-it.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 9a29d0fbc2d9ad99fb8a981ab72548cc360e9d4c Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 14 Dec 2016 15:05:38 -0800
Subject: relay: check array offset before using it

From: Dan Carpenter <dan.carpenter@oracle.com>

commit 9a29d0fbc2d9ad99fb8a981ab72548cc360e9d4c upstream.

Smatch complains that we started using the array offset before we
checked that it was valid.

Fixes: 017c59c042d0 ('relay: Use per CPU constructs for the relay channel buffer pointers')
Link: http://lkml.kernel.org/r/20161013084947.GC16198@mwanda
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 kernel/relay.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -809,11 +809,11 @@ void relay_subbufs_consumed(struct rchan
 {
 	struct rchan_buf *buf;
 
-	if (!chan)
+	if (!chan || cpu >= NR_CPUS)
 		return;
 
 	buf = *per_cpu_ptr(chan->buf, cpu);
-	if (cpu >= NR_CPUS || !buf || subbufs_consumed > chan->n_subbufs)
+	if (!buf || subbufs_consumed > chan->n_subbufs)
 		return;
 
 	if (subbufs_consumed > buf->subbufs_produced - buf->subbufs_consumed)


Patches currently in stable-queue which might be from dan.carpenter@oracle.com are

queue-4.9/staging-media-davinci_vpfe-unlock-on-error-in-vpfe_reqbufs.patch
queue-4.9/mmc-mmc_test-uninitialized-return-value.patch
queue-4.9/relay-check-array-offset-before-using-it.patch
queue-4.9/target-iscsi-fix-double-free-in-lio_target_tiqn_addtpg.patch
queue-4.9/s390-crypto-unlock-on-error-in-prng_tdes_read.patch
queue-4.9/usb-xhci-mem-use-passed-in-gfp-flags-instead-of-gfp_kernel.patch
queue-4.9/iommu-amd-missing-error-code-in-amd_iommu_init_device.patch
queue-4.9/efi-efivar_ssdt_load-don-t-return-success-on-allocation-failure.patch
queue-4.9/asoc-intel-skylake-fix-a-shift-wrapping-bug.patch
queue-4.9/input-synaptics-rmi4-unlock-on-error.patch