This is a note to let you know that I've just added the patch titled xfrm/compat: prevent potential spectre v1 gadget in xfrm_xlate32_attr() to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xfrm-compat-prevent-potential-spectre-v1-gadget-in-x.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit cf66cdd2a9f692b1f9bff5411bbcc71c87244cdb Author: Eric Dumazet <edumazet@xxxxxxxxxx> Date: Fri Jan 20 13:02:49 2023 +0000 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 <edumazet@xxxxxxxxxx> Cc: Dmitry Safonov <dima@xxxxxxxxxx> Cc: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> Reviewed-by: Dmitry Safonov <dima@xxxxxxxxxx> Signed-off-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/xfrm/xfrm_compat.c b/net/xfrm/xfrm_compat.c index 12405aa5bce84..8cbf45a8bcdc2 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 <fw@xxxxxxxxx> */ #include <linux/compat.h> +#include <linux/nospec.h> #include <linux/xfrm.h> #include <net/xfrm.h> @@ -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;