[PATCH AUTOSEL 4.19 19/97] ieee802154: hwsim: fix off-by-one in parse nested

From: Sasha Levin
Date: Wed Dec 26 2018 - 18:01:27 EST


From: Alexander Aring <aring@xxxxxxxxxxxx>

[ Upstream commit a73d4e1490913b76b292f91553b7ba08a65caa3f ]

This patch fixes a off-by-one mistake in nla_parse_nested() functions of
mac802154_hwsim driver. I had to enabled stack protector so I was able
to reproduce it.

Reference: https://github.com/linux-wpan/wpan-tools/issues/17

Signed-off-by: Alexander Aring <aring@xxxxxxxxxxxx>
Signed-off-by: Stefan Schmidt <stefan@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ieee802154/mac802154_hwsim.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ieee802154/mac802154_hwsim.c b/drivers/net/ieee802154/mac802154_hwsim.c
index bf70ab892e69..624bff4d3636 100644
--- a/drivers/net/ieee802154/mac802154_hwsim.c
+++ b/drivers/net/ieee802154/mac802154_hwsim.c
@@ -500,7 +500,7 @@ static int hwsim_del_edge_nl(struct sk_buff *msg, struct genl_info *info)
!info->attrs[MAC802154_HWSIM_ATTR_RADIO_EDGE])
return -EINVAL;

- if (nla_parse_nested(edge_attrs, MAC802154_HWSIM_EDGE_ATTR_MAX + 1,
+ if (nla_parse_nested(edge_attrs, MAC802154_HWSIM_EDGE_ATTR_MAX,
info->attrs[MAC802154_HWSIM_ATTR_RADIO_EDGE],
hwsim_edge_policy, NULL))
return -EINVAL;
@@ -550,7 +550,7 @@ static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
!info->attrs[MAC802154_HWSIM_ATTR_RADIO_EDGE])
return -EINVAL;

- if (nla_parse_nested(edge_attrs, MAC802154_HWSIM_EDGE_ATTR_MAX + 1,
+ if (nla_parse_nested(edge_attrs, MAC802154_HWSIM_EDGE_ATTR_MAX,
info->attrs[MAC802154_HWSIM_ATTR_RADIO_EDGE],
hwsim_edge_policy, NULL))
return -EINVAL;
--
2.19.1