From 419674224390fca298020fc0751a20812f84b12d Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 20 Jan 2023 13:02:49 +0000 Subject: [PATCH] xfrm/compat: prevent potential spectre v1 gadget in xfrm_xlate32_attr() [ Upstream commit b6ee896385380aa621102e8ea402ba12db1cabff ] int type = nla_type(nla); if (type > XFRMA_MAX) { return -EOPNOTSUPP; } @type is then used as an array index and can be used as a Spectre v1 gadget. if (nla_len(nla) < compat_policy[type].len) { array_index_nospec() can be used to prevent leaking content of kernel memory to malicious users. Fixes: 5106f4a8acff ("xfrm/compat: Add 32=>64-bit messages translator") Signed-off-by: Eric Dumazet Cc: Dmitry Safonov Cc: Steffen Klassert Reviewed-by: Dmitry Safonov Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin --- net/xfrm/xfrm_compat.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/xfrm/xfrm_compat.c b/net/xfrm/xfrm_compat.c index 12405aa..8cbf45a 100644 --- a/net/xfrm/xfrm_compat.c +++ b/net/xfrm/xfrm_compat.c @@ -5,6 +5,7 @@ * Based on code and translator idea by: Florian Westphal */ #include +#include #include #include @@ -437,6 +438,7 @@ static int xfrm_xlate32_attr(void *dst, const struct nlattr *nla, NL_SET_ERR_MSG(extack, "Bad attribute"); return -EOPNOTSUPP; } + type = array_index_nospec(type, XFRMA_MAX + 1); if (nla_len(nla) < compat_policy[type].len) { NL_SET_ERR_MSG(extack, "Attribute bad length"); return -EOPNOTSUPP; -- 2.7.4