commit 4e9505064f upstream.
The attribute-translator has to take in mind maxtype, that is
xfrm_link::nla_max. When it is set, attributes are not of xfrm_attr_type_t.
Currently, they can be only XFRMA_SPD_MAX (message XFRM_MSG_NEWSPDINFO),
their UABI is the same for 64/32-bit, so just copy them.
Thanks to YueHaibing for reporting this:
In xfrm_user_rcv_msg_compat() if maxtype is not zero and less than
XFRMA_MAX, nlmsg_parse_deprecated() do not initialize attrs array fully.
xfrm_xlate32() will access uninit 'attrs[i]' while iterating all attrs
array.
KASAN: probably user-memory-access in range [0x0000000041b58ab0-0x0000000041b58ab7]
CPU: 0 PID: 15799 Comm: syz-executor.2 Tainted: G W 5.14.0-rc1-syzkaller #0
RIP: 0010:nla_type include/net/netlink.h:1130 [inline]
RIP: 0010:xfrm_xlate32_attr net/xfrm/xfrm_compat.c:410 [inline]
RIP: 0010:xfrm_xlate32 net/xfrm/xfrm_compat.c:532 [inline]
RIP: 0010:xfrm_user_rcv_msg_compat+0x5e5/0x1070 net/xfrm/xfrm_compat.c:577
[...]
Call Trace:
xfrm_user_rcv_msg+0x556/0x8b0 net/xfrm/xfrm_user.c:2774
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
xfrm_netlink_rcv+0x6b/0x90 net/xfrm/xfrm_user.c:2824
netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
sock_sendmsg_nosec net/socket.c:702 [inline]
Fixes: 5106f4a8ac ("xfrm/compat: Add 32=>64-bit messages translator")
Cc: <stable@kernel.org>
Reported-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
afcd5a0e01