Stanislav Fomichev 600c70bad6 bpf: allow wide (u64) aligned stores for some fields of bpf_sock_addr
Since commit cd17d7770578 ("bpf/tools: sync bpf.h") clang decided
that it can do a single u64 store into user_ip6[2] instead of two
separate u32 ones:

 #  17: (18) r2 = 0x100000000000000
 #  ; ctx->user_ip6[2] = bpf_htonl(DST_REWRITE_IP6_2);
 #  19: (7b) *(u64 *)(r1 +16) = r2
 #  invalid bpf_context access off=16 size=8

>From the compiler point of view it does look like a correct thing
to do, so let's support it on the kernel side.

Credit to Andrii Nakryiko for a proper implementation of
bpf_ctx_wide_store_ok.

Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Fixes: cd17d7770578 ("bpf/tools: sync bpf.h")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-08 16:22:55 +02:00
..
2019-02-24 11:40:45 +01:00
2019-04-08 21:29:16 -04:00
2019-06-13 17:33:34 +02:00