diff options
| author | Jason A. Donenfeld <Jason@zx2c4.com> | 2022-09-16 17:37:40 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-09-20 21:26:14 +0300 |
| commit | 26c013108c12b94bc023bf19198a4300596c98b1 (patch) | |
| tree | c713b038b1f48a571e68da4a7035e3a396e40374 | |
| parent | 8e25c02b8cce7063ae9f08cad51d246a60370bc9 (diff) | |
| download | linux-26c013108c12b94bc023bf19198a4300596c98b1.tar.xz | |
wireguard: netlink: avoid variable-sized memcpy on sockaddr
Doing a variable-sized memcpy is slower, and the compiler isn't smart
enough to turn this into a constant-size assignment.
Further, Kees' latest fortified memcpy will actually bark, because the
destination pointer is type sockaddr, not explicitly sockaddr_in or
sockaddr_in6, so it thinks there's an overflow:
memcpy: detected field-spanning write (size 28) of single field
"&endpoint.addr" at drivers/net/wireguard/netlink.c:446 (size 16)
Fix this by just assigning by using explicit casts for each checked
case.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reported-by: syzbot+a448cda4dba2dac50de5@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/wireguard/netlink.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/drivers/net/wireguard/netlink.c b/drivers/net/wireguard/netlink.c index d0f3b6d7f408..5c804bcabfe6 100644 --- a/drivers/net/wireguard/netlink.c +++ b/drivers/net/wireguard/netlink.c @@ -436,14 +436,13 @@ static int set_peer(struct wg_device *wg, struct nlattr **attrs) if (attrs[WGPEER_A_ENDPOINT]) { struct sockaddr *addr = nla_data(attrs[WGPEER_A_ENDPOINT]); size_t len = nla_len(attrs[WGPEER_A_ENDPOINT]); + struct endpoint endpoint = { { { 0 } } }; - if ((len == sizeof(struct sockaddr_in) && - addr->sa_family == AF_INET) || - (len == sizeof(struct sockaddr_in6) && - addr->sa_family == AF_INET6)) { - struct endpoint endpoint = { { { 0 } } }; - - memcpy(&endpoint.addr, addr, len); + if (len == sizeof(struct sockaddr_in) && addr->sa_family == AF_INET) { + endpoint.addr4 = *(struct sockaddr_in *)addr; + wg_socket_set_peer_endpoint(peer, &endpoint); + } else if (len == sizeof(struct sockaddr_in6) && addr->sa_family == AF_INET6) { + endpoint.addr6 = *(struct sockaddr_in6 *)addr; wg_socket_set_peer_endpoint(peer, &endpoint); } } |