GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-03-15 19:55:32 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

netlink: prevent potential spectre v1 gadgets

Browse source 
[ Upstream commit f0950402e8 ]

Most netlink attributes are parsed and validated from
__nla_validate_parse() or validate_nla()

    u16 type = nla_type(nla);

    if (type == 0 || type > maxtype) {
        /* error or continue */
    }

@type is then used as an array index and can be used
as a Spectre v1 gadget.

array_index_nospec() can be used to prevent leaking
content of kernel memory to malicious users.

This should take care of vast majority of netlink uses,
but an audit is needed to take care of others where
validation is not yet centralized in core netlink functions.

Fixes: bfa83a9e03 ("[NETLINK]: Type-safe netlink messages/attributes interface")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230119110150.2678537-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Eric Dumazet 2023-01-19 11:01:50 +00:00 • committed by Justin Hammond
parent 8851ecda7d
commit be26994e61
1 changed files with 3 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
lib/nlattr.c
View file

@ -10,6 +10,7 @@
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/jiffies.h>
#include <linux/nospec.h>
#include <linux/skbuff.h>
#include <linux/string.h>
#include <linux/types.h>
@ -369,6 +370,7 @@ static int validate_nla(const struct nlattr *nla, int maxtype,
if (type <= 0 || type > maxtype)
return 0;
type = array_index_nospec(type, maxtype + 1);
pt = &policy[type];
BUG_ON(pt->type > NLA_TYPE_MAX);
@ -584,6 +586,7 @@ static int __nla_validate_parse(const struct nlattr *head, int len, int maxtype,
}
continue;
}
type = array_index_nospec(type, maxtype + 1);
if (policy) {
int err = validate_nla(nla, maxtype, policy,
validate, extack, depth);