diff mbox series

[v2,bpf-next,1/6] selftests/bpf: Fix bind program for big endian systems

Message ID 20240412165230.2009746-2-jrife@google.com
State Superseded
Headers show
Series selftests/bpf: Add sockaddr tests for kernel networking | expand

Commit Message

Jordan Rife April 12, 2024, 4:52 p.m. UTC
Without this fix, the bind4 and bind6 programs will reject bind attempts
on big endian systems. This patch ensures that CI tests pass for the
s390x architecture.

Signed-off-by: Jordan Rife <jrife@google.com>
---
 .../testing/selftests/bpf/progs/bind4_prog.c  | 18 ++++++++++--------
 .../testing/selftests/bpf/progs/bind6_prog.c  | 18 ++++++++++--------
 tools/testing/selftests/bpf/progs/bind_prog.h | 19 +++++++++++++++++++
 3 files changed, 39 insertions(+), 16 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/progs/bind_prog.h

Comments

Jordan Rife April 13, 2024, 1:19 a.m. UTC | #1
Kui-Feng,

You are right. Maybe simply "load_word" and "load_byte" would be a
better name here. WDYT?

-Jordan


On Fri, Apr 12, 2024 at 6:01 PM Kui-Feng Lee <sinquersw@gmail.com> wrote:
>
>
>
> On 4/12/24 09:52, Jordan Rife wrote:
> > Without this fix, the bind4 and bind6 programs will reject bind attempts
> > on big endian systems. This patch ensures that CI tests pass for the
> > s390x architecture.
> >
> > Signed-off-by: Jordan Rife <jrife@google.com>
> > ---
> >   .../testing/selftests/bpf/progs/bind4_prog.c  | 18 ++++++++++--------
> >   .../testing/selftests/bpf/progs/bind6_prog.c  | 18 ++++++++++--------
> >   tools/testing/selftests/bpf/progs/bind_prog.h | 19 +++++++++++++++++++
> >   3 files changed, 39 insertions(+), 16 deletions(-)
> >   create mode 100644 tools/testing/selftests/bpf/progs/bind_prog.h
> >
> > diff --git a/tools/testing/selftests/bpf/progs/bind4_prog.c b/tools/testing/selftests/bpf/progs/bind4_prog.c
> > index a487f60b73ac4..2bc052ecb6eef 100644
> > --- a/tools/testing/selftests/bpf/progs/bind4_prog.c
> > +++ b/tools/testing/selftests/bpf/progs/bind4_prog.c
> > @@ -12,6 +12,8 @@
> >   #include <bpf/bpf_helpers.h>
> >   #include <bpf/bpf_endian.h>
> >
> > +#include "bind_prog.h"
> > +
> >   #define SERV4_IP            0xc0a801feU /* 192.168.1.254 */
> >   #define SERV4_PORT          4040
> >   #define SERV4_REWRITE_IP    0x7f000001U /* 127.0.0.1 */
> > @@ -118,23 +120,23 @@ int bind_v4_prog(struct bpf_sock_addr *ctx)
> >
> >       // u8 narrow loads:
> >       user_ip4 = 0;
> > -     user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[0] << 0;
> > -     user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[1] << 8;
> > -     user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[2] << 16;
> > -     user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[3] << 24;
> > +     user_ip4 |= load_byte_ntoh(ctx->user_ip4, 0, sizeof(user_ip4));
> > +     user_ip4 |= load_byte_ntoh(ctx->user_ip4, 1, sizeof(user_ip4));
> > +     user_ip4 |= load_byte_ntoh(ctx->user_ip4, 2, sizeof(user_ip4));
> > +     user_ip4 |= load_byte_ntoh(ctx->user_ip4, 3, sizeof(user_ip4));
> >       if (ctx->user_ip4 != user_ip4)
> >               return 0;
> >
> >       user_port = 0;
> > -     user_port |= ((volatile __u8 *)&ctx->user_port)[0] << 0;
> > -     user_port |= ((volatile __u8 *)&ctx->user_port)[1] << 8;
> > +     user_port |= load_byte_ntoh(ctx->user_port, 0, sizeof(user_port));
> > +     user_port |= load_byte_ntoh(ctx->user_port, 1, sizeof(user_port));
> >       if (ctx->user_port != user_port)
> >               return 0;
> >
> >       // u16 narrow loads:
> >       user_ip4 = 0;
> > -     user_ip4 |= ((volatile __u16 *)&ctx->user_ip4)[0] << 0;
> > -     user_ip4 |= ((volatile __u16 *)&ctx->user_ip4)[1] << 16;
> > +     user_ip4 |= load_word_ntoh(ctx->user_ip4, 0, sizeof(user_ip4));
> > +     user_ip4 |= load_word_ntoh(ctx->user_ip4, 1, sizeof(user_ip4));
> >       if (ctx->user_ip4 != user_ip4)
> >               return 0;
> >
> > diff --git a/tools/testing/selftests/bpf/progs/bind6_prog.c b/tools/testing/selftests/bpf/progs/bind6_prog.c
> > index d62cd9e9cf0ea..194583e3375bf 100644
> > --- a/tools/testing/selftests/bpf/progs/bind6_prog.c
> > +++ b/tools/testing/selftests/bpf/progs/bind6_prog.c
> > @@ -12,6 +12,8 @@
> >   #include <bpf/bpf_helpers.h>
> >   #include <bpf/bpf_endian.h>
> >
> > +#include "bind_prog.h"
> > +
> >   #define SERV6_IP_0          0xfaceb00c /* face:b00c:1234:5678::abcd */
> >   #define SERV6_IP_1          0x12345678
> >   #define SERV6_IP_2          0x00000000
> > @@ -129,25 +131,25 @@ int bind_v6_prog(struct bpf_sock_addr *ctx)
> >       // u8 narrow loads:
> >       for (i = 0; i < 4; i++) {
> >               user_ip6 = 0;
> > -             user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[0] << 0;
> > -             user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[1] << 8;
> > -             user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[2] << 16;
> > -             user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[3] << 24;
> > +             user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 0, sizeof(user_ip6));
> > +             user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 1, sizeof(user_ip6));
> > +             user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 2, sizeof(user_ip6));
> > +             user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 3, sizeof(user_ip6));
> >               if (ctx->user_ip6[i] != user_ip6)
> >                       return 0;
> >       }
> >
> >       user_port = 0;
> > -     user_port |= ((volatile __u8 *)&ctx->user_port)[0] << 0;
> > -     user_port |= ((volatile __u8 *)&ctx->user_port)[1] << 8;
> > +     user_port |= load_byte_ntoh(ctx->user_port, 0, sizeof(user_port));
> > +     user_port |= load_byte_ntoh(ctx->user_port, 1, sizeof(user_port));
> >       if (ctx->user_port != user_port)
> >               return 0;
> >
> >       // u16 narrow loads:
> >       for (i = 0; i < 4; i++) {
> >               user_ip6 = 0;
> > -             user_ip6 |= ((volatile __u16 *)&ctx->user_ip6[i])[0] << 0;
> > -             user_ip6 |= ((volatile __u16 *)&ctx->user_ip6[i])[1] << 16;
> > +             user_ip6 |= load_word_ntoh(ctx->user_ip6[i], 0, sizeof(user_ip6));
> > +             user_ip6 |= load_word_ntoh(ctx->user_ip6[i], 1, sizeof(user_ip6));
> >               if (ctx->user_ip6[i] != user_ip6)
> >                       return 0;
> >       }
> > diff --git a/tools/testing/selftests/bpf/progs/bind_prog.h b/tools/testing/selftests/bpf/progs/bind_prog.h
> > new file mode 100644
> > index 0000000000000..0fdc466aec346
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/progs/bind_prog.h
> > @@ -0,0 +1,19 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +#ifndef __BIND_PROG_H__
> > +#define __BIND_PROG_H__
> > +
> > +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
> > +#define load_byte_ntoh(src, b, s) \
> > +     (((volatile __u8 *)&(src))[b] << 8 * b)
> > +#define load_word_ntoh(src, w, s) \
> > +     (((volatile __u16 *)&(src))[w] << 16 * w)
> > +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> > +#define load_byte_ntoh(src, b, s) \
> > +     (((volatile __u8 *)&(src))[(b) + (sizeof(src) - (s))] << 8 * ((s) - (b) - 1))
> > +#define load_word_ntoh(src, w, s) \
> > +     (((volatile __u16 *)&(src))[w] << 16 * (((s) / 2) - (w) - 1))
> These names, load_byte_ntoh() and load_word_ntoh(), are miss-leading.
>
> They don't actually do byte-order conversion from network order to host
> order. Network order is big endian. 0xdeadbeef in u32 should be stored
> as the sequence of
>
>    0xde, 0xad, 0xbe, 0xef
>
> The little endian implementation of load_word_ntoh() provided here will
> return 0xadde and 0xefbe0000. However, a network order to host order
> conversion should return 0xbeef and 0xdead0000 for little endian.
>
> The little endian implementation of load_byte_ntoh() here returns 0xde,
> 0xad00, 0xbe0000, and 0xef000000. However, a network to host order
> conversion should return 0xef, 0xbe00, 0xad0000, and 0xde00000.
>
> So, they just access raw data following the host byte order, not
> providing any byte order conversion.
>
>
> > +#else
> > +# error "Fix your compiler's __BYTE_ORDER__?!"
> > +#endif
> > +
> > +#endif
Kui-Feng Lee April 13, 2024, 1:28 a.m. UTC | #2
On 4/12/24 18:17, Jordan Rife wrote:
> Kui-Feng,
> 
> You are right. Maybe simply "load_word" and "load_byte" would be a 
> better name here. WDYT?

Agree!


> 
> -Jordan
> 
> 
> On Fri, Apr 12, 2024 at 6:01 PM Kui-Feng Lee <sinquersw@gmail.com 
> <mailto:sinquersw@gmail.com>> wrote:
> 
> 
> 
>     On 4/12/24 09:52, Jordan Rife wrote:
>      > Without this fix, the bind4 and bind6 programs will reject bind
>     attempts
>      > on big endian systems. This patch ensures that CI tests pass for the
>      > s390x architecture.
>      >
>      > Signed-off-by: Jordan Rife <jrife@google.com
>     <mailto:jrife@google.com>>
>      > ---
>      >   .../testing/selftests/bpf/progs/bind4_prog.c  | 18
>     ++++++++++--------
>      >   .../testing/selftests/bpf/progs/bind6_prog.c  | 18
>     ++++++++++--------
>      >   tools/testing/selftests/bpf/progs/bind_prog.h | 19
>     +++++++++++++++++++
>      >   3 files changed, 39 insertions(+), 16 deletions(-)
>      >   create mode 100644 tools/testing/selftests/bpf/progs/bind_prog.h
>      >
>      > diff --git a/tools/testing/selftests/bpf/progs/bind4_prog.c
>     b/tools/testing/selftests/bpf/progs/bind4_prog.c
>      > index a487f60b73ac4..2bc052ecb6eef 100644
>      > --- a/tools/testing/selftests/bpf/progs/bind4_prog.c
>      > +++ b/tools/testing/selftests/bpf/progs/bind4_prog.c
>      > @@ -12,6 +12,8 @@
>      >   #include <bpf/bpf_helpers.h>
>      >   #include <bpf/bpf_endian.h>
>      >
>      > +#include "bind_prog.h"
>      > +
>      >   #define SERV4_IP            0xc0a801feU /* 192.168.1.254 */
>      >   #define SERV4_PORT          4040
>      >   #define SERV4_REWRITE_IP    0x7f000001U /* 127.0.0.1 */
>      > @@ -118,23 +120,23 @@ int bind_v4_prog(struct bpf_sock_addr *ctx)
>      >
>      >       // u8 narrow loads:
>      >       user_ip4 = 0;
>      > -     user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[0] << 0;
>      > -     user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[1] << 8;
>      > -     user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[2] << 16;
>      > -     user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[3] << 24;
>      > +     user_ip4 |= load_byte_ntoh(ctx->user_ip4, 0, sizeof(user_ip4));
>      > +     user_ip4 |= load_byte_ntoh(ctx->user_ip4, 1, sizeof(user_ip4));
>      > +     user_ip4 |= load_byte_ntoh(ctx->user_ip4, 2, sizeof(user_ip4));
>      > +     user_ip4 |= load_byte_ntoh(ctx->user_ip4, 3, sizeof(user_ip4));
>      >       if (ctx->user_ip4 != user_ip4)
>      >               return 0;
>      >
>      >       user_port = 0;
>      > -     user_port |= ((volatile __u8 *)&ctx->user_port)[0] << 0;
>      > -     user_port |= ((volatile __u8 *)&ctx->user_port)[1] << 8;
>      > +     user_port |= load_byte_ntoh(ctx->user_port, 0,
>     sizeof(user_port));
>      > +     user_port |= load_byte_ntoh(ctx->user_port, 1,
>     sizeof(user_port));
>      >       if (ctx->user_port != user_port)
>      >               return 0;
>      >
>      >       // u16 narrow loads:
>      >       user_ip4 = 0;
>      > -     user_ip4 |= ((volatile __u16 *)&ctx->user_ip4)[0] << 0;
>      > -     user_ip4 |= ((volatile __u16 *)&ctx->user_ip4)[1] << 16;
>      > +     user_ip4 |= load_word_ntoh(ctx->user_ip4, 0, sizeof(user_ip4));
>      > +     user_ip4 |= load_word_ntoh(ctx->user_ip4, 1, sizeof(user_ip4));
>      >       if (ctx->user_ip4 != user_ip4)
>      >               return 0;
>      >
>      > diff --git a/tools/testing/selftests/bpf/progs/bind6_prog.c
>     b/tools/testing/selftests/bpf/progs/bind6_prog.c
>      > index d62cd9e9cf0ea..194583e3375bf 100644
>      > --- a/tools/testing/selftests/bpf/progs/bind6_prog.c
>      > +++ b/tools/testing/selftests/bpf/progs/bind6_prog.c
>      > @@ -12,6 +12,8 @@
>      >   #include <bpf/bpf_helpers.h>
>      >   #include <bpf/bpf_endian.h>
>      >
>      > +#include "bind_prog.h"
>      > +
>      >   #define SERV6_IP_0          0xfaceb00c /*
>     face:b00c:1234:5678::abcd */
>      >   #define SERV6_IP_1          0x12345678
>      >   #define SERV6_IP_2          0x00000000
>      > @@ -129,25 +131,25 @@ int bind_v6_prog(struct bpf_sock_addr *ctx)
>      >       // u8 narrow loads:
>      >       for (i = 0; i < 4; i++) {
>      >               user_ip6 = 0;
>      > -             user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[0]
>     << 0;
>      > -             user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[1]
>     << 8;
>      > -             user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[2]
>     << 16;
>      > -             user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[3]
>     << 24;
>      > +             user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 0,
>     sizeof(user_ip6));
>      > +             user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 1,
>     sizeof(user_ip6));
>      > +             user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 2,
>     sizeof(user_ip6));
>      > +             user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 3,
>     sizeof(user_ip6));
>      >               if (ctx->user_ip6[i] != user_ip6)
>      >                       return 0;
>      >       }
>      >
>      >       user_port = 0;
>      > -     user_port |= ((volatile __u8 *)&ctx->user_port)[0] << 0;
>      > -     user_port |= ((volatile __u8 *)&ctx->user_port)[1] << 8;
>      > +     user_port |= load_byte_ntoh(ctx->user_port, 0,
>     sizeof(user_port));
>      > +     user_port |= load_byte_ntoh(ctx->user_port, 1,
>     sizeof(user_port));
>      >       if (ctx->user_port != user_port)
>      >               return 0;
>      >
>      >       // u16 narrow loads:
>      >       for (i = 0; i < 4; i++) {
>      >               user_ip6 = 0;
>      > -             user_ip6 |= ((volatile __u16
>     *)&ctx->user_ip6[i])[0] << 0;
>      > -             user_ip6 |= ((volatile __u16
>     *)&ctx->user_ip6[i])[1] << 16;
>      > +             user_ip6 |= load_word_ntoh(ctx->user_ip6[i], 0,
>     sizeof(user_ip6));
>      > +             user_ip6 |= load_word_ntoh(ctx->user_ip6[i], 1,
>     sizeof(user_ip6));
>      >               if (ctx->user_ip6[i] != user_ip6)
>      >                       return 0;
>      >       }
>      > diff --git a/tools/testing/selftests/bpf/progs/bind_prog.h
>     b/tools/testing/selftests/bpf/progs/bind_prog.h
>      > new file mode 100644
>      > index 0000000000000..0fdc466aec346
>      > --- /dev/null
>      > +++ b/tools/testing/selftests/bpf/progs/bind_prog.h
>      > @@ -0,0 +1,19 @@
>      > +/* SPDX-License-Identifier: GPL-2.0 */
>      > +#ifndef __BIND_PROG_H__
>      > +#define __BIND_PROG_H__
>      > +
>      > +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
>      > +#define load_byte_ntoh(src, b, s) \
>      > +     (((volatile __u8 *)&(src))[b] << 8 * b)
>      > +#define load_word_ntoh(src, w, s) \
>      > +     (((volatile __u16 *)&(src))[w] << 16 * w)
>      > +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
>      > +#define load_byte_ntoh(src, b, s) \
>      > +     (((volatile __u8 *)&(src))[(b) + (sizeof(src) - (s))] << 8
>     * ((s) - (b) - 1))
>      > +#define load_word_ntoh(src, w, s) \
>      > +     (((volatile __u16 *)&(src))[w] << 16 * (((s) / 2) - (w) - 1))
>     These names, load_byte_ntoh() and load_word_ntoh(), are miss-leading.
> 
>     They don't actually do byte-order conversion from network order to host
>     order. Network order is big endian. 0xdeadbeef in u32 should be stored
>     as the sequence of
> 
>         0xde, 0xad, 0xbe, 0xef
> 
>     The little endian implementation of load_word_ntoh() provided here will
>     return 0xadde and 0xefbe0000. However, a network order to host order
>     conversion should return 0xbeef and 0xdead0000 for little endian.
> 
>     The little endian implementation of load_byte_ntoh() here returns 0xde,
>     0xad00, 0xbe0000, and 0xef000000. However, a network to host order
>     conversion should return 0xef, 0xbe00, 0xad0000, and 0xde00000.
> 
>     So, they just access raw data following the host byte order, not
>     providing any byte order conversion.
> 
> 
>      > +#else
>      > +# error "Fix your compiler's __BYTE_ORDER__?!"
>      > +#endif
>      > +
>      > +#endif
>
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/progs/bind4_prog.c b/tools/testing/selftests/bpf/progs/bind4_prog.c
index a487f60b73ac4..2bc052ecb6eef 100644
--- a/tools/testing/selftests/bpf/progs/bind4_prog.c
+++ b/tools/testing/selftests/bpf/progs/bind4_prog.c
@@ -12,6 +12,8 @@ 
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_endian.h>
 
+#include "bind_prog.h"
+
 #define SERV4_IP		0xc0a801feU /* 192.168.1.254 */
 #define SERV4_PORT		4040
 #define SERV4_REWRITE_IP	0x7f000001U /* 127.0.0.1 */
@@ -118,23 +120,23 @@  int bind_v4_prog(struct bpf_sock_addr *ctx)
 
 	// u8 narrow loads:
 	user_ip4 = 0;
-	user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[0] << 0;
-	user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[1] << 8;
-	user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[2] << 16;
-	user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[3] << 24;
+	user_ip4 |= load_byte_ntoh(ctx->user_ip4, 0, sizeof(user_ip4));
+	user_ip4 |= load_byte_ntoh(ctx->user_ip4, 1, sizeof(user_ip4));
+	user_ip4 |= load_byte_ntoh(ctx->user_ip4, 2, sizeof(user_ip4));
+	user_ip4 |= load_byte_ntoh(ctx->user_ip4, 3, sizeof(user_ip4));
 	if (ctx->user_ip4 != user_ip4)
 		return 0;
 
 	user_port = 0;
-	user_port |= ((volatile __u8 *)&ctx->user_port)[0] << 0;
-	user_port |= ((volatile __u8 *)&ctx->user_port)[1] << 8;
+	user_port |= load_byte_ntoh(ctx->user_port, 0, sizeof(user_port));
+	user_port |= load_byte_ntoh(ctx->user_port, 1, sizeof(user_port));
 	if (ctx->user_port != user_port)
 		return 0;
 
 	// u16 narrow loads:
 	user_ip4 = 0;
-	user_ip4 |= ((volatile __u16 *)&ctx->user_ip4)[0] << 0;
-	user_ip4 |= ((volatile __u16 *)&ctx->user_ip4)[1] << 16;
+	user_ip4 |= load_word_ntoh(ctx->user_ip4, 0, sizeof(user_ip4));
+	user_ip4 |= load_word_ntoh(ctx->user_ip4, 1, sizeof(user_ip4));
 	if (ctx->user_ip4 != user_ip4)
 		return 0;
 
diff --git a/tools/testing/selftests/bpf/progs/bind6_prog.c b/tools/testing/selftests/bpf/progs/bind6_prog.c
index d62cd9e9cf0ea..194583e3375bf 100644
--- a/tools/testing/selftests/bpf/progs/bind6_prog.c
+++ b/tools/testing/selftests/bpf/progs/bind6_prog.c
@@ -12,6 +12,8 @@ 
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_endian.h>
 
+#include "bind_prog.h"
+
 #define SERV6_IP_0		0xfaceb00c /* face:b00c:1234:5678::abcd */
 #define SERV6_IP_1		0x12345678
 #define SERV6_IP_2		0x00000000
@@ -129,25 +131,25 @@  int bind_v6_prog(struct bpf_sock_addr *ctx)
 	// u8 narrow loads:
 	for (i = 0; i < 4; i++) {
 		user_ip6 = 0;
-		user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[0] << 0;
-		user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[1] << 8;
-		user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[2] << 16;
-		user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[3] << 24;
+		user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 0, sizeof(user_ip6));
+		user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 1, sizeof(user_ip6));
+		user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 2, sizeof(user_ip6));
+		user_ip6 |= load_byte_ntoh(ctx->user_ip6[i], 3, sizeof(user_ip6));
 		if (ctx->user_ip6[i] != user_ip6)
 			return 0;
 	}
 
 	user_port = 0;
-	user_port |= ((volatile __u8 *)&ctx->user_port)[0] << 0;
-	user_port |= ((volatile __u8 *)&ctx->user_port)[1] << 8;
+	user_port |= load_byte_ntoh(ctx->user_port, 0, sizeof(user_port));
+	user_port |= load_byte_ntoh(ctx->user_port, 1, sizeof(user_port));
 	if (ctx->user_port != user_port)
 		return 0;
 
 	// u16 narrow loads:
 	for (i = 0; i < 4; i++) {
 		user_ip6 = 0;
-		user_ip6 |= ((volatile __u16 *)&ctx->user_ip6[i])[0] << 0;
-		user_ip6 |= ((volatile __u16 *)&ctx->user_ip6[i])[1] << 16;
+		user_ip6 |= load_word_ntoh(ctx->user_ip6[i], 0, sizeof(user_ip6));
+		user_ip6 |= load_word_ntoh(ctx->user_ip6[i], 1, sizeof(user_ip6));
 		if (ctx->user_ip6[i] != user_ip6)
 			return 0;
 	}
diff --git a/tools/testing/selftests/bpf/progs/bind_prog.h b/tools/testing/selftests/bpf/progs/bind_prog.h
new file mode 100644
index 0000000000000..0fdc466aec346
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bind_prog.h
@@ -0,0 +1,19 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __BIND_PROG_H__
+#define __BIND_PROG_H__
+
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#define load_byte_ntoh(src, b, s) \
+	(((volatile __u8 *)&(src))[b] << 8 * b)
+#define load_word_ntoh(src, w, s) \
+	(((volatile __u16 *)&(src))[w] << 16 * w)
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#define load_byte_ntoh(src, b, s) \
+	(((volatile __u8 *)&(src))[(b) + (sizeof(src) - (s))] << 8 * ((s) - (b) - 1))
+#define load_word_ntoh(src, w, s) \
+	(((volatile __u16 *)&(src))[w] << 16 * (((s) / 2) - (w) - 1))
+#else
+# error "Fix your compiler's __BYTE_ORDER__?!"
+#endif
+
+#endif