From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> [ 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@xxxxxxxxxx> Acked-by: Jukka Rissanen <jukka.rissanen@xxxxxxxxxxxxxxx> Acked-by: Alexander Aring <aring@xxxxxxxxxxxx> Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/6lowpan/nhc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/6lowpan/nhc.c b/net/6lowpan/nhc.c index 4fa2fdda174d..9e56fb98f33c 100644 --- a/net/6lowpan/nhc.c +++ b/net/6lowpan/nhc.c @@ -18,7 +18,7 @@ #include "nhc.h" static struct rb_root rb_root = RB_ROOT; -static struct lowpan_nhc *lowpan_nexthdr_nhcs[NEXTHDR_MAX]; +static struct lowpan_nhc *lowpan_nexthdr_nhcs[NEXTHDR_MAX + 1]; static DEFINE_SPINLOCK(lowpan_nhc_lock); static int lowpan_nhc_insert(struct lowpan_nhc *nhc) -- 2.20.1