4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Roded Zats rzats@paloaltonetworks.com
[ Upstream commit 1aec77b2bb2ed1db0f5efc61c4c1ca3813307489 ]
Each attribute inside a nested IFLA_VF_VLAN_LIST is assumed to be a struct ifla_vf_vlan_info so the size of such attribute needs to be at least of sizeof(struct ifla_vf_vlan_info) which is 14 bytes. The current size validation in do_setvfinfo is against NLA_HDRLEN (4 bytes) which is less than sizeof(struct ifla_vf_vlan_info) so this validation is not enough and a too small attribute might be cast to a struct ifla_vf_vlan_info, this might result in an out of bands read access when accessing the saved (casted) entry in ivvl.
Fixes: 79aab093a0b5 ("net: Update API for VF vlan protocol 802.1ad support") Signed-off-by: Roded Zats rzats@paloaltonetworks.com Reviewed-by: Donald Hunter donald.hunter@gmail.com Link: https://lore.kernel.org/r/20240502155751.75705-1-rzats@paloaltonetworks.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/rtnetlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 0d3f724da78ba..9209623ab6445 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2167,7 +2167,7 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb)
nla_for_each_nested(attr, tb[IFLA_VF_VLAN_LIST], rem) { if (nla_type(attr) != IFLA_VF_VLAN_INFO || - nla_len(attr) < NLA_HDRLEN) { + nla_len(attr) < sizeof(struct ifla_vf_vlan_info)) { return -EINVAL; } if (len >= MAX_VLAN_LIST_LEN)