On Thu, 2020-09-10 at 09:55 -0700, Andrii Nakryiko wrote:
> On Wed, Sep 9, 2020 at 6:59 PM Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
> wrote:
> > This test makes a lot of narrow load checks while assuming little
> > endian architecture, and therefore fails on s390.
> >
> > Fix by introducing LSB and LSW macros and using them to perform
> > narrow
> > loads.
> >
> > Fixes: 0ab5539f8584 ("selftests/bpf: Tests for BPF_SK_LOOKUP attach
> > point")
> > Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
> > ---
>
> Jakub,
>
> Can you please help review this to make sure no error accidentally
> slipped in?
Gentle ping.
>
> > .../selftests/bpf/progs/test_sk_lookup.c | 264 ++++++++++--
> > ------
> > 1 file changed, 149 insertions(+), 115 deletions(-)
> >
> > diff --git a/tools/testing/selftests/bpf/progs/test_sk_lookup.c
> > b/tools/testing/selftests/bpf/progs/test_sk_lookup.c
> > index bbf8296f4d66..94e6d370967b 100644
> > --- a/tools/testing/selftests/bpf/progs/test_sk_lookup.c
> > +++ b/tools/testing/selftests/bpf/progs/test_sk_lookup.c
> > @@ -19,6 +19,17 @@
> > #define IP6(aaaa, bbbb, cccc, dddd) \
> > { bpf_htonl(aaaa), bpf_htonl(bbbb), bpf_htonl(cccc),
> > bpf_htonl(dddd) }
> >
> > +/* Macros for least-significant byte and word accesses. */
> > +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
> > +#define LSE_INDEX(index, size) (index)
> > +#else
> > +#define LSE_INDEX(index, size) ((size) - (index) - 1)
> > +#endif
> > +#define LSB(value, index) \
> > + (((__u8 *)&(value))[LSE_INDEX((index), sizeof(value))])
> > +#define LSW(value, index) \
> > + (((__u16 *)&(value))[LSE_INDEX((index), sizeof(value) /
> > 2)])
> > +
> > #define MAX_SOCKS 32
> >
> > struct {
> > @@ -369,171 +380,194 @@ int ctx_narrow_access(struct bpf_sk_lookup
> > *ctx)
> > {
> > struct bpf_sock *sk;
> > int err, family;
> > - __u16 *half;
> > - __u8 *byte;
> > bool v4;
> >
> > v4 = (ctx->family == AF_INET);
> >
> > /* Narrow loads from family field */
> > - byte = (__u8 *)&ctx->family;
> > - half = (__u16 *)&ctx->family;
> > - if (byte[0] != (v4 ? AF_INET : AF_INET6) ||
> > - byte[1] != 0 || byte[2] != 0 || byte[3] != 0)
> > + if (LSB(ctx->family, 0) != (v4 ? AF_INET : AF_INET6) ||
> > + LSB(ctx->family, 1) != 0 || LSB(ctx->family, 2) != 0 ||
> > + LSB(ctx->family, 3) != 0)
> > return SK_DROP;
> > - if (half[0] != (v4 ? AF_INET : AF_INET6))
> > + if (LSW(ctx->family, 0) != (v4 ? AF_INET : AF_INET6))
> > return SK_DROP;
> >
> > - byte = (__u8 *)&ctx->protocol;
> > - if (byte[0] != IPPROTO_TCP ||
> > - byte[1] != 0 || byte[2] != 0 || byte[3] != 0)
> > + /* Narrow loads from protocol field */
> > + if (LSB(ctx->protocol, 0) != IPPROTO_TCP ||
> > + LSB(ctx->protocol, 1) != 0 || LSB(ctx->protocol, 2) !=
> > 0 ||
> > + LSB(ctx->protocol, 3) != 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->protocol;
> > - if (half[0] != IPPROTO_TCP)
> > + if (LSW(ctx->protocol, 0) != IPPROTO_TCP)
> > return SK_DROP;
> >
> > /* Narrow loads from remote_port field. Expect non-0 value.
> > */
> > - byte = (__u8 *)&ctx->remote_port;
> > - if (byte[0] == 0 && byte[1] == 0 && byte[2] == 0 && byte[3]
> > == 0)
> > + if (LSB(ctx->remote_port, 0) == 0 && LSB(ctx->remote_port,
> > 1) == 0 &&
> > + LSB(ctx->remote_port, 2) == 0 && LSB(ctx->remote_port,
> > 3) == 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->remote_port;
> > - if (half[0] == 0)
> > + if (LSW(ctx->remote_port, 0) == 0)
> > return SK_DROP;
> >
> > /* Narrow loads from local_port field. Expect DST_PORT. */
> > - byte = (__u8 *)&ctx->local_port;
> > - if (byte[0] != ((DST_PORT >> 0) & 0xff) ||
> > - byte[1] != ((DST_PORT >> 8) & 0xff) ||
> > - byte[2] != 0 || byte[3] != 0)
> > + if (LSB(ctx->local_port, 0) != ((DST_PORT >> 0) & 0xff) ||
> > + LSB(ctx->local_port, 1) != ((DST_PORT >> 8) & 0xff) ||
> > + LSB(ctx->local_port, 2) != 0 || LSB(ctx->local_port, 3)
> > != 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->local_port;
> > - if (half[0] != DST_PORT)
> > + if (LSW(ctx->local_port, 0) != DST_PORT)
> > return SK_DROP;
> >
> > /* Narrow loads from IPv4 fields */
> > if (v4) {
> > /* Expect non-0.0.0.0 in remote_ip4 */
> > - byte = (__u8 *)&ctx->remote_ip4;
> > - if (byte[0] == 0 && byte[1] == 0 &&
> > - byte[2] == 0 && byte[3] == 0)
> > + if (LSB(ctx->remote_ip4, 0) == 0 &&
> > + LSB(ctx->remote_ip4, 1) == 0 &&
> > + LSB(ctx->remote_ip4, 2) == 0 &&
> > + LSB(ctx->remote_ip4, 3) == 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->remote_ip4;
> > - if (half[0] == 0 && half[1] == 0)
> > + if (LSW(ctx->remote_ip4, 0) == 0 &&
> > + LSW(ctx->remote_ip4, 1) == 0)
> > return SK_DROP;
> >
> > /* Expect DST_IP4 in local_ip4 */
> > - byte = (__u8 *)&ctx->local_ip4;
> > - if (byte[0] != ((DST_IP4 >> 0) & 0xff) ||
> > - byte[1] != ((DST_IP4 >> 8) & 0xff) ||
> > - byte[2] != ((DST_IP4 >> 16) & 0xff) ||
> > - byte[3] != ((DST_IP4 >> 24) & 0xff))
> > + if (LSB(ctx->local_ip4, 0) != ((DST_IP4 >> 0) &
> > 0xff) ||
> > + LSB(ctx->local_ip4, 1) != ((DST_IP4 >> 8) &
> > 0xff) ||
> > + LSB(ctx->local_ip4, 2) != ((DST_IP4 >> 16) &
> > 0xff) ||
> > + LSB(ctx->local_ip4, 3) != ((DST_IP4 >> 24) &
> > 0xff))
> > return SK_DROP;
> > - half = (__u16 *)&ctx->local_ip4;
> > - if (half[0] != ((DST_IP4 >> 0) & 0xffff) ||
> > - half[1] != ((DST_IP4 >> 16) & 0xffff))
> > + if (LSW(ctx->local_ip4, 0) != ((DST_IP4 >> 0) &
> > 0xffff) ||
> > + LSW(ctx->local_ip4, 1) != ((DST_IP4 >> 16) &
> > 0xffff))
> > return SK_DROP;
> > } else {
> > /* Expect 0.0.0.0 IPs when family != AF_INET */
> > - byte = (__u8 *)&ctx->remote_ip4;
> > - if (byte[0] != 0 || byte[1] != 0 &&
> > - byte[2] != 0 || byte[3] != 0)
> > + if (LSB(ctx->remote_ip4, 0) != 0 ||
> > + LSB(ctx->remote_ip4, 1) != 0 ||
> > + LSB(ctx->remote_ip4, 2) != 0 ||
> > + LSB(ctx->remote_ip4, 3) != 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->remote_ip4;
> > - if (half[0] != 0 || half[1] != 0)
> > + if (LSW(ctx->remote_ip4, 0) != 0 ||
> > + LSW(ctx->remote_ip4, 1) != 0)
> > return SK_DROP;
> >
> > - byte = (__u8 *)&ctx->local_ip4;
> > - if (byte[0] != 0 || byte[1] != 0 &&
> > - byte[2] != 0 || byte[3] != 0)
> > + if (LSB(ctx->local_ip4, 0) != 0 ||
> > + LSB(ctx->local_ip4, 1) != 0 ||
> > + LSB(ctx->local_ip4, 2) != 0 || LSB(ctx-
> > >local_ip4, 3) != 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->local_ip4;
> > - if (half[0] != 0 || half[1] != 0)
> > + if (LSW(ctx->local_ip4, 0) != 0 || LSW(ctx-
> > >local_ip4, 1) != 0)
> > return SK_DROP;
> > }
> >
> > /* Narrow loads from IPv6 fields */
> > if (!v4) {
> > - /* Expenct non-:: IP in remote_ip6 */
> > - byte = (__u8 *)&ctx->remote_ip6;
> > - if (byte[0] == 0 && byte[1] == 0 &&
> > - byte[2] == 0 && byte[3] == 0 &&
> > - byte[4] == 0 && byte[5] == 0 &&
> > - byte[6] == 0 && byte[7] == 0 &&
> > - byte[8] == 0 && byte[9] == 0 &&
> > - byte[10] == 0 && byte[11] == 0 &&
> > - byte[12] == 0 && byte[13] == 0 &&
> > - byte[14] == 0 && byte[15] == 0)
> > + /* Expect non-:: IP in remote_ip6 */
> > + if (LSB(ctx->remote_ip6[0], 0) == 0 &&
> > + LSB(ctx->remote_ip6[0], 1) == 0 &&
> > + LSB(ctx->remote_ip6[0], 2) == 0 &&
> > + LSB(ctx->remote_ip6[0], 3) == 0 &&
> > + LSB(ctx->remote_ip6[1], 0) == 0 &&
> > + LSB(ctx->remote_ip6[1], 1) == 0 &&
> > + LSB(ctx->remote_ip6[1], 2) == 0 &&
> > + LSB(ctx->remote_ip6[1], 3) == 0 &&
> > + LSB(ctx->remote_ip6[2], 0) == 0 &&
> > + LSB(ctx->remote_ip6[2], 1) == 0 &&
> > + LSB(ctx->remote_ip6[2], 2) == 0 &&
> > + LSB(ctx->remote_ip6[2], 3) == 0 &&
> > + LSB(ctx->remote_ip6[3], 0) == 0 &&
> > + LSB(ctx->remote_ip6[3], 1) == 0 &&
> > + LSB(ctx->remote_ip6[3], 2) == 0 &&
> > + LSB(ctx->remote_ip6[3], 3) == 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->remote_ip6;
> > - if (half[0] == 0 && half[1] == 0 &&
> > - half[2] == 0 && half[3] == 0 &&
> > - half[4] == 0 && half[5] == 0 &&
> > - half[6] == 0 && half[7] == 0)
> > + if (LSW(ctx->remote_ip6[0], 0) == 0 &&
> > + LSW(ctx->remote_ip6[0], 1) == 0 &&
> > + LSW(ctx->remote_ip6[1], 0) == 0 &&
> > + LSW(ctx->remote_ip6[1], 1) == 0 &&
> > + LSW(ctx->remote_ip6[2], 0) == 0 &&
> > + LSW(ctx->remote_ip6[2], 1) == 0 &&
> > + LSW(ctx->remote_ip6[3], 0) == 0 &&
> > + LSW(ctx->remote_ip6[3], 1) == 0)
> > return SK_DROP;
> > -
> > /* Expect DST_IP6 in local_ip6 */
> > - byte = (__u8 *)&ctx->local_ip6;
> > - if (byte[0] != ((DST_IP6[0] >> 0) & 0xff) ||
> > - byte[1] != ((DST_IP6[0] >> 8) & 0xff) ||
> > - byte[2] != ((DST_IP6[0] >> 16) & 0xff) ||
> > - byte[3] != ((DST_IP6[0] >> 24) & 0xff) ||
> > - byte[4] != ((DST_IP6[1] >> 0) & 0xff) ||
> > - byte[5] != ((DST_IP6[1] >> 8) & 0xff) ||
> > - byte[6] != ((DST_IP6[1] >> 16) & 0xff) ||
> > - byte[7] != ((DST_IP6[1] >> 24) & 0xff) ||
> > - byte[8] != ((DST_IP6[2] >> 0) & 0xff) ||
> > - byte[9] != ((DST_IP6[2] >> 8) & 0xff) ||
> > - byte[10] != ((DST_IP6[2] >> 16) & 0xff) ||
> > - byte[11] != ((DST_IP6[2] >> 24) & 0xff) ||
> > - byte[12] != ((DST_IP6[3] >> 0) & 0xff) ||
> > - byte[13] != ((DST_IP6[3] >> 8) & 0xff) ||
> > - byte[14] != ((DST_IP6[3] >> 16) & 0xff) ||
> > - byte[15] != ((DST_IP6[3] >> 24) & 0xff))
> > + if (LSB(ctx->local_ip6[0], 0) != ((DST_IP6[0] >> 0)
> > & 0xff) ||
> > + LSB(ctx->local_ip6[0], 1) != ((DST_IP6[0] >> 8)
> > & 0xff) ||
> > + LSB(ctx->local_ip6[0], 2) != ((DST_IP6[0] >>
> > 16) & 0xff) ||
> > + LSB(ctx->local_ip6[0], 3) != ((DST_IP6[0] >>
> > 24) & 0xff) ||
> > + LSB(ctx->local_ip6[1], 0) != ((DST_IP6[1] >> 0)
> > & 0xff) ||
> > + LSB(ctx->local_ip6[1], 1) != ((DST_IP6[1] >> 8)
> > & 0xff) ||
> > + LSB(ctx->local_ip6[1], 2) != ((DST_IP6[1] >>
> > 16) & 0xff) ||
> > + LSB(ctx->local_ip6[1], 3) != ((DST_IP6[1] >>
> > 24) & 0xff) ||
> > + LSB(ctx->local_ip6[2], 0) != ((DST_IP6[2] >> 0)
> > & 0xff) ||
> > + LSB(ctx->local_ip6[2], 1) != ((DST_IP6[2] >> 8)
> > & 0xff) ||
> > + LSB(ctx->local_ip6[2], 2) != ((DST_IP6[2] >>
> > 16) & 0xff) ||
> > + LSB(ctx->local_ip6[2], 3) != ((DST_IP6[2] >>
> > 24) & 0xff) ||
> > + LSB(ctx->local_ip6[3], 0) != ((DST_IP6[3] >> 0)
> > & 0xff) ||
> > + LSB(ctx->local_ip6[3], 1) != ((DST_IP6[3] >> 8)
> > & 0xff) ||
> > + LSB(ctx->local_ip6[3], 2) != ((DST_IP6[3] >>
> > 16) & 0xff) ||
> > + LSB(ctx->local_ip6[3], 3) != ((DST_IP6[3] >>
> > 24) & 0xff))
> > return SK_DROP;
> > - half = (__u16 *)&ctx->local_ip6;
> > - if (half[0] != ((DST_IP6[0] >> 0) & 0xffff) ||
> > - half[1] != ((DST_IP6[0] >> 16) & 0xffff) ||
> > - half[2] != ((DST_IP6[1] >> 0) & 0xffff) ||
> > - half[3] != ((DST_IP6[1] >> 16) & 0xffff) ||
> > - half[4] != ((DST_IP6[2] >> 0) & 0xffff) ||
> > - half[5] != ((DST_IP6[2] >> 16) & 0xffff) ||
> > - half[6] != ((DST_IP6[3] >> 0) & 0xffff) ||
> > - half[7] != ((DST_IP6[3] >> 16) & 0xffff))
> > + if (LSW(ctx->local_ip6[0], 0) != ((DST_IP6[0] >> 0)
> > & 0xffff) ||
> > + LSW(ctx->local_ip6[0], 1) !=
> > + ((DST_IP6[0] >> 16) & 0xffff) ||
> > + LSW(ctx->local_ip6[1], 0) != ((DST_IP6[1] >> 0)
> > & 0xffff) ||
> > + LSW(ctx->local_ip6[1], 1) !=
> > + ((DST_IP6[1] >> 16) & 0xffff) ||
> > + LSW(ctx->local_ip6[2], 0) != ((DST_IP6[2] >> 0)
> > & 0xffff) ||
> > + LSW(ctx->local_ip6[2], 1) !=
> > + ((DST_IP6[2] >> 16) & 0xffff) ||
> > + LSW(ctx->local_ip6[3], 0) != ((DST_IP6[3] >> 0)
> > & 0xffff) ||
> > + LSW(ctx->local_ip6[3], 1) != ((DST_IP6[3] >>
> > 16) & 0xffff))
> > return SK_DROP;
> > } else {
> > /* Expect :: IPs when family != AF_INET6 */
> > - byte = (__u8 *)&ctx->remote_ip6;
> > - if (byte[0] != 0 || byte[1] != 0 ||
> > - byte[2] != 0 || byte[3] != 0 ||
> > - byte[4] != 0 || byte[5] != 0 ||
> > - byte[6] != 0 || byte[7] != 0 ||
> > - byte[8] != 0 || byte[9] != 0 ||
> > - byte[10] != 0 || byte[11] != 0 ||
> > - byte[12] != 0 || byte[13] != 0 ||
> > - byte[14] != 0 || byte[15] != 0)
> > + if (LSB(ctx->remote_ip6[0], 0) != 0 ||
> > + LSB(ctx->remote_ip6[0], 1) != 0 ||
> > + LSB(ctx->remote_ip6[0], 2) != 0 ||
> > + LSB(ctx->remote_ip6[0], 3) != 0 ||
> > + LSB(ctx->remote_ip6[1], 0) != 0 ||
> > + LSB(ctx->remote_ip6[1], 1) != 0 ||
> > + LSB(ctx->remote_ip6[1], 2) != 0 ||
> > + LSB(ctx->remote_ip6[1], 3) != 0 ||
> > + LSB(ctx->remote_ip6[2], 0) != 0 ||
> > + LSB(ctx->remote_ip6[2], 1) != 0 ||
> > + LSB(ctx->remote_ip6[2], 2) != 0 ||
> > + LSB(ctx->remote_ip6[2], 3) != 0 ||
> > + LSB(ctx->remote_ip6[3], 0) != 0 ||
> > + LSB(ctx->remote_ip6[3], 1) != 0 ||
> > + LSB(ctx->remote_ip6[3], 2) != 0 ||
> > + LSB(ctx->remote_ip6[3], 3) != 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->remote_ip6;
> > - if (half[0] != 0 || half[1] != 0 ||
> > - half[2] != 0 || half[3] != 0 ||
> > - half[4] != 0 || half[5] != 0 ||
> > - half[6] != 0 || half[7] != 0)
> > + if (LSW(ctx->remote_ip6[0], 0) != 0 ||
> > + LSW(ctx->remote_ip6[0], 1) != 0 ||
> > + LSW(ctx->remote_ip6[1], 0) != 0 ||
> > + LSW(ctx->remote_ip6[1], 1) != 0 ||
> > + LSW(ctx->remote_ip6[2], 0) != 0 ||
> > + LSW(ctx->remote_ip6[2], 1) != 0 ||
> > + LSW(ctx->remote_ip6[3], 0) != 0 ||
> > + LSW(ctx->remote_ip6[3], 1) != 0)
> > return SK_DROP;
> >
> > - byte = (__u8 *)&ctx->local_ip6;
> > - if (byte[0] != 0 || byte[1] != 0 ||
> > - byte[2] != 0 || byte[3] != 0 ||
> > - byte[4] != 0 || byte[5] != 0 ||
> > - byte[6] != 0 || byte[7] != 0 ||
> > - byte[8] != 0 || byte[9] != 0 ||
> > - byte[10] != 0 || byte[11] != 0 ||
> > - byte[12] != 0 || byte[13] != 0 ||
> > - byte[14] != 0 || byte[15] != 0)
> > + if (LSB(ctx->local_ip6[0], 0) != 0 ||
> > + LSB(ctx->local_ip6[0], 1) != 0 ||
> > + LSB(ctx->local_ip6[0], 2) != 0 ||
> > + LSB(ctx->local_ip6[0], 3) != 0 ||
> > + LSB(ctx->local_ip6[1], 0) != 0 ||
> > + LSB(ctx->local_ip6[1], 1) != 0 ||
> > + LSB(ctx->local_ip6[1], 2) != 0 ||
> > + LSB(ctx->local_ip6[1], 3) != 0 ||
> > + LSB(ctx->local_ip6[2], 0) != 0 ||
> > + LSB(ctx->local_ip6[2], 1) != 0 ||
> > + LSB(ctx->local_ip6[2], 2) != 0 ||
> > + LSB(ctx->local_ip6[2], 3) != 0 ||
> > + LSB(ctx->local_ip6[3], 0) != 0 ||
> > + LSB(ctx->local_ip6[3], 1) != 0 ||
> > + LSB(ctx->local_ip6[3], 2) != 0 ||
> > + LSB(ctx->local_ip6[3], 3) != 0)
> > return SK_DROP;
> > - half = (__u16 *)&ctx->local_ip6;
> > - if (half[0] != 0 || half[1] != 0 ||
> > - half[2] != 0 || half[3] != 0 ||
> > - half[4] != 0 || half[5] != 0 ||
> > - half[6] != 0 || half[7] != 0)
> > + if (LSW(ctx->remote_ip6[0], 0) != 0 ||
> > + LSW(ctx->remote_ip6[0], 1) != 0 ||
> > + LSW(ctx->remote_ip6[1], 0) != 0 ||
> > + LSW(ctx->remote_ip6[1], 1) != 0 ||
> > + LSW(ctx->remote_ip6[2], 0) != 0 ||
> > + LSW(ctx->remote_ip6[2], 1) != 0 ||
> > + LSW(ctx->remote_ip6[3], 0) != 0 ||
> > + LSW(ctx->remote_ip6[3], 1) != 0)
> > return SK_DROP;
> > }
> >
> > --
> > 2.25.4
> >
