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[v3,bpf-next,00/15] bpf: net: Remove duplicated code from bpf_setsockopt()

Message ID 20220810190724.2692127-1-kafai@fb.com (mailing list archive)
Headers show
Series bpf: net: Remove duplicated code from bpf_setsockopt() | expand

Message

Martin KaFai Lau Aug. 10, 2022, 7:07 p.m. UTC
The code in bpf_setsockopt() is mostly a copy-and-paste from
the sock_setsockopt(), do_tcp_setsockopt(), do_ipv6_setsockopt(),
and do_ip_setsockopt().  As the allowed optnames in bpf_setsockopt()
grows, so are the duplicated code.  The code between the copies
also slowly drifted.

This set is an effort to clean this up and reuse the existing
{sock,do_tcp,do_ipv6,do_ip}_setsockopt() as much as possible.

After the clean up, this set also adds a few allowed optnames
that we need to the bpf_setsockopt().

The initial attempt was to clean up both bpf_setsockopt() and
bpf_getsockopt() together.  However, the patch set was getting
too long.  It is beneficial to leave the bpf_getsockopt()
out for another patch set.  Thus, this set is focusing
on the bpf_setsockopt().

v3:
- s/in_bpf/has_current_bpf_ctx/ (Andrii)
- Add comments to has_current_bpf_ctx() and sockopt_lock_sock()
  (Stanislav)
- Use vmlinux.h in selftest and add defines to bpf_tracing_net.h
  (Stanislav)
- Use bpf_getsockopt(SO_MARK) in selftest (Stanislav)
- Use BPF_CORE_READ_BITFIELD in selftest (Yonghong)

v2:
- A major change is to use in_bpf() to test if a setsockopt()
  is called by a bpf prog and use in_bpf() to skip capable
  check.  Suggested by Stanislav.
- Instead of passing is_locked through sockptr_t or through an extra
  argument to sk_setsockopt, v2 uses in_bpf() to skip the lock_sock()
  also because bpf prog has the lock acquired.
- No change to the current sockptr_t in this revision
- s/codes/code/

Martin KaFai Lau (15):
  net: Add sk_setsockopt() to take the sk ptr instead of the sock ptr
  bpf: net: Avoid sk_setsockopt() taking sk lock when called from bpf
  bpf: net: Consider has_current_bpf_ctx() when testing capable() in
    sk_setsockopt()
  bpf: net: Change do_tcp_setsockopt() to use the sockopt's lock_sock()
    and capable()
  bpf: net: Change do_ip_setsockopt() to use the sockopt's lock_sock()
    and capable()
  bpf: net: Change do_ipv6_setsockopt() to use the sockopt's lock_sock()
    and capable()
  bpf: Initialize the bpf_run_ctx in bpf_iter_run_prog()
  bpf: Embed kernel CONFIG check into the if statement in bpf_setsockopt
  bpf: Change bpf_setsockopt(SOL_SOCKET) to reuse sk_setsockopt()
  bpf: Refactor bpf specific tcp optnames to a new function
  bpf: Change bpf_setsockopt(SOL_TCP) to reuse do_tcp_setsockopt()
  bpf: Change bpf_setsockopt(SOL_IP) to reuse do_ip_setsockopt()
  bpf: Change bpf_setsockopt(SOL_IPV6) to reuse do_ipv6_setsockopt()
  bpf: Add a few optnames to bpf_setsockopt
  selftests/bpf: bpf_setsockopt tests

 include/linux/bpf.h                           |  14 +
 include/net/ip.h                              |   2 +
 include/net/ipv6.h                            |   2 +
 include/net/ipv6_stubs.h                      |   2 +
 include/net/sock.h                            |   7 +
 include/net/tcp.h                             |   2 +
 kernel/bpf/bpf_iter.c                         |   5 +
 net/core/filter.c                             | 377 ++++++---------
 net/core/sock.c                               |  81 +++-
 net/ipv4/ip_sockglue.c                        |  16 +-
 net/ipv4/tcp.c                                |  22 +-
 net/ipv6/af_inet6.c                           |   1 +
 net/ipv6/ipv6_sockglue.c                      |  18 +-
 .../selftests/bpf/prog_tests/setget_sockopt.c | 125 +++++
 .../selftests/bpf/progs/bpf_tracing_net.h     |  31 +-
 .../selftests/bpf/progs/setget_sockopt.c      | 451 ++++++++++++++++++
 16 files changed, 883 insertions(+), 273 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/setget_sockopt.c
 create mode 100644 tools/testing/selftests/bpf/progs/setget_sockopt.c

Comments

Stanislav Fomichev Aug. 11, 2022, 5:04 p.m. UTC | #1
On 08/10, Martin KaFai Lau wrote:
> The code in bpf_setsockopt() is mostly a copy-and-paste from
> the sock_setsockopt(), do_tcp_setsockopt(), do_ipv6_setsockopt(),
> and do_ip_setsockopt().  As the allowed optnames in bpf_setsockopt()
> grows, so are the duplicated code.  The code between the copies
> also slowly drifted.

> This set is an effort to clean this up and reuse the existing
> {sock,do_tcp,do_ipv6,do_ip}_setsockopt() as much as possible.

> After the clean up, this set also adds a few allowed optnames
> that we need to the bpf_setsockopt().

> The initial attempt was to clean up both bpf_setsockopt() and
> bpf_getsockopt() together.  However, the patch set was getting
> too long.  It is beneficial to leave the bpf_getsockopt()
> out for another patch set.  Thus, this set is focusing
> on the bpf_setsockopt().

> v3:
> - s/in_bpf/has_current_bpf_ctx/ (Andrii)
> - Add comments to has_current_bpf_ctx() and sockopt_lock_sock()
>    (Stanislav)
> - Use vmlinux.h in selftest and add defines to bpf_tracing_net.h
>    (Stanislav)
> - Use bpf_getsockopt(SO_MARK) in selftest (Stanislav)
> - Use BPF_CORE_READ_BITFIELD in selftest (Yonghong)

Reviewed-by: Stanislav Fomichev <sdf@google.com>

(I didn't go super deep on the selftest)
Daniel Borkmann Aug. 15, 2022, 10:04 p.m. UTC | #2
On 8/11/22 7:04 PM, sdf@google.com wrote:
> On 08/10, Martin KaFai Lau wrote:
>> The code in bpf_setsockopt() is mostly a copy-and-paste from
>> the sock_setsockopt(), do_tcp_setsockopt(), do_ipv6_setsockopt(),
>> and do_ip_setsockopt().  As the allowed optnames in bpf_setsockopt()
>> grows, so are the duplicated code.  The code between the copies
>> also slowly drifted.
> 
>> This set is an effort to clean this up and reuse the existing
>> {sock,do_tcp,do_ipv6,do_ip}_setsockopt() as much as possible.
> 
>> After the clean up, this set also adds a few allowed optnames
>> that we need to the bpf_setsockopt().
> 
>> The initial attempt was to clean up both bpf_setsockopt() and
>> bpf_getsockopt() together.  However, the patch set was getting
>> too long.  It is beneficial to leave the bpf_getsockopt()
>> out for another patch set.  Thus, this set is focusing
>> on the bpf_setsockopt().
> 
>> v3:
>> - s/in_bpf/has_current_bpf_ctx/ (Andrii)
>> - Add comments to has_current_bpf_ctx() and sockopt_lock_sock()
>>    (Stanislav)
>> - Use vmlinux.h in selftest and add defines to bpf_tracing_net.h
>>    (Stanislav)
>> - Use bpf_getsockopt(SO_MARK) in selftest (Stanislav)
>> - Use BPF_CORE_READ_BITFIELD in selftest (Yonghong)
> 
> Reviewed-by: Stanislav Fomichev <sdf@google.com>
> 
> (I didn't go super deep on the selftest)

Looks like that one throws a build error, fwiw:

https://github.com/kernel-patches/bpf/runs/7844497492?check_suite_focus=true

   [...]
     CLNG-BPF [test_maps] kfunc_call_test_subprog.o
     CLNG-BPF [test_maps] bpf_iter_test_kern6.o
   progs/setget_sockopt.c:39:33: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
           { .opt = SO_REUSEADDR, .flip = 1, },
                                          ^
   progs/setget_sockopt.c:42:33: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
           { .opt = SO_KEEPALIVE, .flip = 1, },
                                          ^
   progs/setget_sockopt.c:44:33: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
           { .opt = SO_REUSEPORT, .flip = 1, },
                                          ^
     CLNG-BPF [test_maps] btf__core_reloc_type_id.o
   progs/setget_sockopt.c:48:32: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
           { .opt = SO_TXREHASH, .flip = 1, },
                                         ^
   progs/setget_sockopt.c:53:32: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
           { .opt = TCP_NODELAY, .flip = 1, },
                                         ^
   progs/setget_sockopt.c:61:45: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
           { .opt = TCP_THIN_LINEAR_TIMEOUTS, .flip = 1, },
                                                      ^
   progs/setget_sockopt.c:75:39: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
           { .opt = IPV6_AUTOFLOWLABEL, .flip = 1, },
                                                ^
   7 errors generated.
   make: *** [Makefile:521: /tmp/runner/work/bpf/bpf/tools/testing/selftests/bpf/setget_sockopt.o] Error 1
   make: *** Waiting for unfinished jobs....
   make: Leaving directory '/tmp/runner/work/bpf/bpf/tools/testing/selftests/bpf'
   Error: Process completed with exit code 2.
Martin KaFai Lau Aug. 17, 2022, 5:23 a.m. UTC | #3
On Tue, Aug 16, 2022 at 12:04:52AM +0200, Daniel Borkmann wrote:
> On 8/11/22 7:04 PM, sdf@google.com wrote:
> > On 08/10, Martin KaFai Lau wrote:
> > > The code in bpf_setsockopt() is mostly a copy-and-paste from
> > > the sock_setsockopt(), do_tcp_setsockopt(), do_ipv6_setsockopt(),
> > > and do_ip_setsockopt().  As the allowed optnames in bpf_setsockopt()
> > > grows, so are the duplicated code.  The code between the copies
> > > also slowly drifted.
> > 
> > > This set is an effort to clean this up and reuse the existing
> > > {sock,do_tcp,do_ipv6,do_ip}_setsockopt() as much as possible.
> > 
> > > After the clean up, this set also adds a few allowed optnames
> > > that we need to the bpf_setsockopt().
> > 
> > > The initial attempt was to clean up both bpf_setsockopt() and
> > > bpf_getsockopt() together.  However, the patch set was getting
> > > too long.  It is beneficial to leave the bpf_getsockopt()
> > > out for another patch set.  Thus, this set is focusing
> > > on the bpf_setsockopt().
> > 
> > > v3:
> > > - s/in_bpf/has_current_bpf_ctx/ (Andrii)
> > > - Add comments to has_current_bpf_ctx() and sockopt_lock_sock()
> > >    (Stanislav)
> > > - Use vmlinux.h in selftest and add defines to bpf_tracing_net.h
> > >    (Stanislav)
> > > - Use bpf_getsockopt(SO_MARK) in selftest (Stanislav)
> > > - Use BPF_CORE_READ_BITFIELD in selftest (Yonghong)
> > 
> > Reviewed-by: Stanislav Fomichev <sdf@google.com>
> > 
> > (I didn't go super deep on the selftest)
> 
> Looks like that one throws a build error, fwiw:
> 
> https://github.com/kernel-patches/bpf/runs/7844497492?check_suite_focus=true
> 
>   [...]
>     CLNG-BPF [test_maps] kfunc_call_test_subprog.o
>     CLNG-BPF [test_maps] bpf_iter_test_kern6.o
>   progs/setget_sockopt.c:39:33: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
>           { .opt = SO_REUSEADDR, .flip = 1, },
>                                          ^
>   progs/setget_sockopt.c:42:33: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
>           { .opt = SO_KEEPALIVE, .flip = 1, },
>                                          ^
>   progs/setget_sockopt.c:44:33: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
>           { .opt = SO_REUSEPORT, .flip = 1, },
>                                          ^
>     CLNG-BPF [test_maps] btf__core_reloc_type_id.o
>   progs/setget_sockopt.c:48:32: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
>           { .opt = SO_TXREHASH, .flip = 1, },
>                                         ^
>   progs/setget_sockopt.c:53:32: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
>           { .opt = TCP_NODELAY, .flip = 1, },
>                                         ^
>   progs/setget_sockopt.c:61:45: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
>           { .opt = TCP_THIN_LINEAR_TIMEOUTS, .flip = 1, },
>                                                      ^
>   progs/setget_sockopt.c:75:39: error: implicit truncation from 'int' to bit-field changes value from 1 to -1 [-Werror,-Wbitfield-constant-conversion]
>           { .opt = IPV6_AUTOFLOWLABEL, .flip = 1, },
>                                                ^
>   7 errors generated.
>   make: *** [Makefile:521: /tmp/runner/work/bpf/bpf/tools/testing/selftests/bpf/setget_sockopt.o] Error 1
>   make: *** Waiting for unfinished jobs....
>   make: Leaving directory '/tmp/runner/work/bpf/bpf/tools/testing/selftests/bpf'
>   Error: Process completed with exit code 2.
Thanks for the report.  I also see it after moving from clang 15 to 16.
I will address it in v4.