6lowpan: Off by one handling ->nexthdr
authorDan Carpenter <dan.carpenter@oracle.com>
Wed, 3 Apr 2019 05:34:16 +0000 (08:34 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 29 Jan 2020 09:24:22 +0000 (10:24 +0100)
commitb0604e2aac44e8800eed1d1e55995b6caeb6a460
treee92e7ed22c359df63e6a4ab6162e0bde43168f09
parent17b41f8c06420a5be73d9a43411a373796e3da74
6lowpan: Off by one handling ->nexthdr

[ Upstream commit f57c4bbf34439531adccd7d3a4ecc14f409c1399 ]

NEXTHDR_MAX is 255.  What happens here is that we take a u8 value
"hdr->nexthdr" from the network and then look it up in
lowpan_nexthdr_nhcs[].  The problem is that if hdr->nexthdr is 0xff then
we read one element beyond the end of the array so the array needs to
be one element larger.

Fixes: 92aa7c65d295 ("6lowpan: add generic nhc layer interface")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Acked-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net/6lowpan/nhc.c