From 1fbc2e0cfcf9677683aea2b1f9ea76fbdc6fb6d1 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Sat, 2 Jun 2018 23:06:37 +0200 Subject: bpf: make sure to clear unused fields in tunnel/xfrm state fetch Since the remaining bits are not filled in struct bpf_tunnel_key resp. struct bpf_xfrm_state and originate from uninitialized stack space, we should make sure to clear them before handing control back to the program. Also add a padding element to struct bpf_xfrm_state for future use similar as we have in struct bpf_tunnel_key and clear it as well. struct bpf_xfrm_state { __u32 reqid; /* 0 4 */ __u32 spi; /* 4 4 */ __u16 family; /* 8 2 */ /* XXX 2 bytes hole, try to pack */ union { __u32 remote_ipv4; /* 4 */ __u32 remote_ipv6[4]; /* 16 */ }; /* 12 16 */ /* size: 28, cachelines: 1, members: 4 */ /* sum members: 26, holes: 1, sum holes: 2 */ /* last cacheline: 28 bytes */ }; Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Acked-by: Song Liu Signed-off-by: Alexei Starovoitov --- include/uapi/linux/bpf.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 661318141f72..f0b6608b1f1c 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -2268,7 +2268,7 @@ struct bpf_tunnel_key { }; __u8 tunnel_tos; __u8 tunnel_ttl; - __u16 tunnel_ext; + __u16 tunnel_ext; /* Padding, future use. */ __u32 tunnel_label; }; @@ -2279,6 +2279,7 @@ struct bpf_xfrm_state { __u32 reqid; __u32 spi; /* Stored in network byte order */ __u16 family; + __u16 ext; /* Padding, future use. */ union { __u32 remote_ipv4; /* Stored in network byte order */ __u32 remote_ipv6[4]; /* Stored in network byte order */ -- cgit v1.2.3-59-g8ed1b