ipv4: prevent potential spectre v1 gadget in fib_metrics_match()

[ Upstream commit 5e9398a26a ]

if (!type)
        continue;
    if (type > RTAX_MAX)
        return false;
    ...
    fi_val = fi->fib_metrics->metrics[type - 1];

@type being used as an array index, we need to prevent
cpu speculation or risk leaking kernel memory content.

Fixes: 5f9ae3d9e7 ("ipv4: do metrics match when looking up and deleting a route")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230120133140.3624204-1-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 2023-01-20 13:31:40 +00:00 committed by Greg Kroah-Hartman
parent 6850fe301d
commit f9753ebd61
1 changed files with 2 additions and 0 deletions

View File

@ -30,6 +30,7 @@
#include <linux/slab.h>
#include <linux/netlink.h>
#include <linux/hash.h>
#include <linux/nospec.h>
#include <net/arp.h>
#include <net/inet_dscp.h>
@ -1022,6 +1023,7 @@ bool fib_metrics_match(struct fib_config *cfg, struct fib_info *fi)
if (type > RTAX_MAX)
return false;
type = array_index_nospec(type, RTAX_MAX + 1);
if (type == RTAX_CC_ALGO) {
char tmp[TCP_CA_NAME_MAX];
bool ecn_ca = false;