diff options
author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2018-12-22 00:22:29 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2018-12-23 05:41:58 +0300 |
commit | a3ac5817ffe8f81dbe6be1522b499b48bc322e3a (patch) | |
tree | 43411ab4065691f005e57aae92d736debc393989 /net | |
parent | 6b8d95f1795c42161dc0984b6863e95d6acf24ed (diff) | |
download | linux-a3ac5817ffe8f81dbe6be1522b499b48bc322e3a.tar.xz |
can: af_can: Fix Spectre v1 vulnerability
protocol is indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.
This issue was detected with the help of Smatch:
net/can/af_can.c:115 can_get_proto() warn: potential spectre issue 'proto_tab' [w]
Fix this by sanitizing protocol before using it to index proto_tab.
Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].
[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r-- | net/can/af_can.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/can/af_can.c b/net/can/af_can.c index 1684ba5b51eb..cade7250c6d4 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -59,6 +59,7 @@ #include <linux/can/core.h> #include <linux/can/skb.h> #include <linux/ratelimit.h> +#include <linux/nospec.h> #include <net/net_namespace.h> #include <net/sock.h> @@ -136,6 +137,7 @@ static int can_create(struct net *net, struct socket *sock, int protocol, if (protocol < 0 || protocol >= CAN_NPROTO) return -EINVAL; + protocol = array_index_nospec(protocol, CAN_NPROTO); cp = can_get_proto(protocol); |