From: Eric Dumazet <edumazet@xxxxxxxxxx> [ Upstream commit 5e9398a26a92fc402d82ce1f97cc67d832527da0 ] 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: 5f9ae3d9e7e4 ("ipv4: do metrics match when looking up and deleting a route") Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230120133140.3624204-1-edumazet@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/ipv4/fib_semantics.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index ce9ff3c62e84..3bb890a40ed7 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -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; -- 2.39.0