Merge branch 'Split bpf_sk_lookup remote_port field'
Jakub Sitnicki says:
====================
Following the recent split-up of the bpf_sock dst_port field, apply the same to
technique to the bpf_sk_lookup remote_port field to make uAPI more user
friendly.
v1 -> v2:
- Remove remote_port range check and cast to be16 in TEST_RUN for sk_lookup
(kernel test robot)
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index a7f0dde..afe3d0d 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -6453,7 +6453,8 @@ struct bpf_sk_lookup {
__u32 protocol; /* IP protocol (IPPROTO_TCP, IPPROTO_UDP) */
__u32 remote_ip4; /* Network byte order */
__u32 remote_ip6[4]; /* Network byte order */
- __u32 remote_port; /* Network byte order */
+ __be16 remote_port; /* Network byte order */
+ __u16 :16; /* Zero padding */
__u32 local_ip4; /* Network byte order */
__u32 local_ip6[4]; /* Network byte order */
__u32 local_port; /* Host byte order */
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index cb150f7..f080345 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -1147,7 +1147,7 @@ int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog, const union bpf_attr *kat
if (!range_is_zero(user_ctx, offsetofend(typeof(*user_ctx), local_port), sizeof(*user_ctx)))
goto out;
- if (user_ctx->local_port > U16_MAX || user_ctx->remote_port > U16_MAX) {
+ if (user_ctx->local_port > U16_MAX) {
ret = -ERANGE;
goto out;
}
@@ -1155,7 +1155,7 @@ int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog, const union bpf_attr *kat
ctx.family = (u16)user_ctx->family;
ctx.protocol = (u16)user_ctx->protocol;
ctx.dport = (u16)user_ctx->local_port;
- ctx.sport = (__force __be16)user_ctx->remote_port;
+ ctx.sport = user_ctx->remote_port;
switch (ctx.family) {
case AF_INET:
diff --git a/net/core/filter.c b/net/core/filter.c
index 99a0519..83f06d3 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -10843,7 +10843,8 @@ static bool sk_lookup_is_valid_access(int off, int size,
case bpf_ctx_range(struct bpf_sk_lookup, local_ip4):
case bpf_ctx_range_till(struct bpf_sk_lookup, remote_ip6[0], remote_ip6[3]):
case bpf_ctx_range_till(struct bpf_sk_lookup, local_ip6[0], local_ip6[3]):
- case bpf_ctx_range(struct bpf_sk_lookup, remote_port):
+ case offsetof(struct bpf_sk_lookup, remote_port) ...
+ offsetof(struct bpf_sk_lookup, local_ip4) - 1:
case bpf_ctx_range(struct bpf_sk_lookup, local_port):
case bpf_ctx_range(struct bpf_sk_lookup, ingress_ifindex):
bpf_ctx_record_field_size(info, sizeof(__u32));
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index a7f0dde..afe3d0d 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -6453,7 +6453,8 @@ struct bpf_sk_lookup {
__u32 protocol; /* IP protocol (IPPROTO_TCP, IPPROTO_UDP) */
__u32 remote_ip4; /* Network byte order */
__u32 remote_ip6[4]; /* Network byte order */
- __u32 remote_port; /* Network byte order */
+ __be16 remote_port; /* Network byte order */
+ __u16 :16; /* Zero padding */
__u32 local_ip4; /* Network byte order */
__u32 local_ip6[4]; /* Network byte order */
__u32 local_port; /* Host byte order */
diff --git a/tools/testing/selftests/bpf/progs/test_sk_lookup.c b/tools/testing/selftests/bpf/progs/test_sk_lookup.c
index 83b0aaa..bf5b7ca 100644
--- a/tools/testing/selftests/bpf/progs/test_sk_lookup.c
+++ b/tools/testing/selftests/bpf/progs/test_sk_lookup.c
@@ -392,6 +392,7 @@ int ctx_narrow_access(struct bpf_sk_lookup *ctx)
{
struct bpf_sock *sk;
int err, family;
+ __u32 val_u32;
bool v4;
v4 = (ctx->family == AF_INET);
@@ -418,6 +419,11 @@ int ctx_narrow_access(struct bpf_sk_lookup *ctx)
if (LSW(ctx->remote_port, 0) != SRC_PORT)
return SK_DROP;
+ /* Load from remote_port field with zero padding (backward compatibility) */
+ val_u32 = *(__u32 *)&ctx->remote_port;
+ if (val_u32 != bpf_htonl(bpf_ntohs(SRC_PORT) << 16))
+ return SK_DROP;
+
/* Narrow loads from local_port field. Expect DST_PORT. */
if (LSB(ctx->local_port, 0) != ((DST_PORT >> 0) & 0xff) ||
LSB(ctx->local_port, 1) != ((DST_PORT >> 8) & 0xff) ||
