| 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) |
