[PATCH v2 bpf-next 01/11] bpf: Make SOCK_OPS_GET_TCP size independent
From: Lawrence Brakmo <hidden>
Date: 2017-12-22 01:21:06
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [networking] (tcx & tc bpf, sock_addr), networking [general], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Martin KaFai Lau, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Make SOCK_OPS_GET_TCP helper macro size independent (before only worked with 4-byte fields. Signed-off-by: Lawrence Brakmo <redacted> --- net/core/filter.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/net/core/filter.c b/net/core/filter.c
index 130b842..099ff9fd 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c@@ -4449,9 +4449,10 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, break; /* Helper macro for adding read access to tcp_sock fields. */ -#define SOCK_OPS_GET_TCP32(FIELD_NAME) \ +#define SOCK_OPS_GET_TCP(FIELD_NAME) \ do { \ - BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, FIELD_NAME) != 4); \ + BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, FIELD_NAME) > \ + FIELD_SIZEOF(struct bpf_sock_ops, FIELD_NAME)); \ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ struct bpf_sock_ops_kern, \ is_fullsock), \
@@ -4463,16 +4464,18 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, struct bpf_sock_ops_kern, sk),\ si->dst_reg, si->src_reg, \ offsetof(struct bpf_sock_ops_kern, sk));\ - *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, \ + *insn++ = BPF_LDX_MEM(FIELD_SIZEOF(struct tcp_sock, \ + FIELD_NAME), si->dst_reg, \ + si->dst_reg, \ offsetof(struct tcp_sock, FIELD_NAME)); \ } while (0) case offsetof(struct bpf_sock_ops, snd_cwnd): - SOCK_OPS_GET_TCP32(snd_cwnd); + SOCK_OPS_GET_TCP(snd_cwnd); break; case offsetof(struct bpf_sock_ops, srtt_us): - SOCK_OPS_GET_TCP32(srtt_us); + SOCK_OPS_GET_TCP(srtt_us); break; } return insn - insn_buf;
--
2.9.5