Commit Graph

1139969 Commits

Author SHA1 Message Date
Martin KaFai Lau
08388efe59 Merge branch 'xfrm: interface: Add unstable helpers for XFRM metadata'
Eyal Birger says:

====================

This patch series adds xfrm metadata helpers using the unstable kfunc
call interface for the TC-BPF hooks.

This allows steering traffic towards different IPsec connections based
on logic implemented in bpf programs.

The helpers are integrated into the xfrm_interface module. For this
purpose the main functionality of this module is moved to
xfrm_interface_core.c.
---

changes in v6: fix sparse warning in patch 2
changes in v5:
  - avoid cleanup of percpu dsts as detailed in patch 2
changes in v3:
  - tag bpf-next tree instead of ipsec-next
  - add IFLA_XFRM_COLLECT_METADATA sync patch
====================

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-12-05 22:54:25 -08:00
Eyal Birger
90a3a05eb3 selftests/bpf: add xfrm_info tests
Test the xfrm_info kfunc helpers.

The test setup creates three name spaces - NS0, NS1, NS2.

XFRM tunnels are setup between NS0 and the two other NSs.

The kfunc helpers are used to steer traffic from NS0 to the other
NSs based on a userspace populated bpf global variable and validate
that the return traffic had arrived from the desired NS.

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Link: https://lore.kernel.org/r/20221203084659.1837829-5-eyal.birger@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-12-05 22:54:23 -08:00
Eyal Birger
4f4ac4d910 tools: add IFLA_XFRM_COLLECT_METADATA to uapi/linux/if_link.h
Needed for XFRM metadata tests.

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Link: https://lore.kernel.org/r/20221203084659.1837829-4-eyal.birger@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-12-05 21:58:28 -08:00
Eyal Birger
94151f5aa9 xfrm: interface: Add unstable helpers for setting/getting XFRM metadata from TC-BPF
This change adds xfrm metadata helpers using the unstable kfunc call
interface for the TC-BPF hooks. This allows steering traffic towards
different IPsec connections based on logic implemented in bpf programs.

This object is built based on the availability of BTF debug info.

When setting the xfrm metadata, percpu metadata dsts are used in order
to avoid allocating a metadata dst per packet.

In order to guarantee safe module unload, the percpu dsts are allocated
on first use and never freed. The percpu pointer is stored in
net/core/filter.c so that it can be reused on module reload.

The metadata percpu dsts take ownership of the original skb dsts so
that they may be used as part of the xfrm transmission logic - e.g.
for MTU calculations.

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Link: https://lore.kernel.org/r/20221203084659.1837829-3-eyal.birger@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-12-05 21:58:27 -08:00
Eyal Birger
ee9a113ab6 xfrm: interface: rename xfrm_interface.c to xfrm_interface_core.c
This change allows adding additional files to the xfrm_interface module.

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Link: https://lore.kernel.org/r/20221203084659.1837829-2-eyal.birger@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-12-05 21:58:27 -08:00
James Hilliard
ab0350c743 selftests/bpf: Fix conflicts with built-in functions in bpf_iter_ksym
Both tolower and toupper are built in c functions, we should not
redefine them as this can result in a build error.

Fixes the following errors:
progs/bpf_iter_ksym.c:10:20: error: conflicting types for built-in function 'tolower'; expected 'int(int)' [-Werror=builtin-declaration-mismatch]
   10 | static inline char tolower(char c)
      |                    ^~~~~~~
progs/bpf_iter_ksym.c:5:1: note: 'tolower' is declared in header '<ctype.h>'
    4 | #include <bpf/bpf_helpers.h>
  +++ |+#include <ctype.h>
    5 |
progs/bpf_iter_ksym.c:17:20: error: conflicting types for built-in function 'toupper'; expected 'int(int)' [-Werror=builtin-declaration-mismatch]
   17 | static inline char toupper(char c)
      |                    ^~~~~~~
progs/bpf_iter_ksym.c:17:20: note: 'toupper' is declared in header '<ctype.h>'

See background on this sort of issue:
https://stackoverflow.com/a/20582607
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12213

(C99, 7.1.3p1) "All identifiers with external linkage in any of the
following subclauses (including the future library directions) are
always reserved for use as identifiers with external linkage."

This is documented behavior in GCC:
https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#index-std-2

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20221203010847.2191265-1-james.hilliard1@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 19:00:15 -08:00
Eric Dumazet
0a182f8d60 bpf, sockmap: fix race in sock_map_free()
sock_map_free() calls release_sock(sk) without owning a reference
on the socket. This can cause use-after-free as syzbot found [1]

Jakub Sitnicki already took care of a similar issue
in sock_hash_free() in commit 75e68e5bf2 ("bpf, sockhash:
Synchronize delete from bucket list on map free")

[1]
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 3785 at lib/refcount.c:31 refcount_warn_saturate+0x17c/0x1a0 lib/refcount.c:31
Modules linked in:
CPU: 0 PID: 3785 Comm: kworker/u4:6 Not tainted 6.1.0-rc7-syzkaller-00103-gef4d3ea40565 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: events_unbound bpf_map_free_deferred
RIP: 0010:refcount_warn_saturate+0x17c/0x1a0 lib/refcount.c:31
Code: 68 8b 31 c0 e8 75 71 15 fd 0f 0b e9 64 ff ff ff e8 d9 6e 4e fd c6 05 62 9c 3d 0a 01 48 c7 c7 80 bb 68 8b 31 c0 e8 54 71 15 fd <0f> 0b e9 43 ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c a2 fe ff
RSP: 0018:ffffc9000456fb60 EFLAGS: 00010246
RAX: eae59bab72dcd700 RBX: 0000000000000004 RCX: ffff8880207057c0
RDX: 0000000000000000 RSI: 0000000000000201 RDI: 0000000000000000
RBP: 0000000000000004 R08: ffffffff816fdabd R09: fffff520008adee5
R10: fffff520008adee5 R11: 1ffff920008adee4 R12: 0000000000000004
R13: dffffc0000000000 R14: ffff88807b1c6c00 R15: 1ffff1100f638dcf
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30c30000 CR3: 000000000d08e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__refcount_dec include/linux/refcount.h:344 [inline]
refcount_dec include/linux/refcount.h:359 [inline]
__sock_put include/net/sock.h:779 [inline]
tcp_release_cb+0x2d0/0x360 net/ipv4/tcp_output.c:1092
release_sock+0xaf/0x1c0 net/core/sock.c:3468
sock_map_free+0x219/0x2c0 net/core/sock_map.c:356
process_one_work+0x81c/0xd10 kernel/workqueue.c:2289
worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
kthread+0x266/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>

Fixes: 7e81a35302 ("bpf: Sockmap, ensure sock lock held during tear down")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Song Liu <songliubraving@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20221202111640.2745533-1-edumazet@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 18:53:51 -08:00
Toke Høiland-Jørgensen
578ce69ffd bpf: Add dummy type reference to nf_conn___init to fix type deduplication
The bpf_ct_set_nat_info() kfunc is defined in the nf_nat.ko module, and
takes as a parameter the nf_conn___init struct, which is allocated through
the bpf_xdp_ct_alloc() helper defined in the nf_conntrack.ko module.
However, because kernel modules can't deduplicate BTF types between each
other, and the nf_conn___init struct is not referenced anywhere in vmlinux
BTF, this leads to two distinct BTF IDs for the same type (one in each
module). This confuses the verifier, as described here:

https://lore.kernel.org/all/87leoh372s.fsf@toke.dk/

As a workaround, add an explicit BTF_TYPE_EMIT for the type in
net/filter.c, so the type definition gets included in vmlinux BTF. This
way, both modules can refer to the same type ID (as they both build on top
of vmlinux BTF), and the verifier is no longer confused.

v2:

- Use BTF_TYPE_EMIT (which is a statement so it has to be inside a function
  definition; use xdp_func_proto() for this, since this is mostly
  xdp-related).

Fixes: 820dc0523e ("net: netfilter: move bpf_ct_set_nat_info kfunc in nf_nat_bpf.c")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20221201123939.696558-1-toke@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 18:52:20 -08:00
Yonghong Song
41d76c721c bpf: Add sleepable prog tests for cgrp local storage
Add three tests for cgrp local storage support for sleepable progs.
Two tests can load and run properly, one for cgroup_iter, another
for passing current->cgroups->dfl_cgrp to bpf_cgrp_storage_get()
helper. One test has bpf_rcu_read_lock() and failed to load.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221201050449.2785613-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 16:51:18 -08:00
Yonghong Song
2c40d97da1 bpf: Enable sleeptable support for cgrp local storage
Similar to sk/inode/task local storage, enable sleepable support for
cgrp local storage.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221201050444.2785007-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 16:51:18 -08:00
Sreevani Sreejith
8972e18a43 bpf, docs: BPF Iterator Document
Document that describes how BPF iterators work, how to use iterators,
and how to pass parameters in BPF iterators.

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Sreevani Sreejith <psreep@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221202221710.320810-2-ssreevani@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 16:41:22 -08:00
Yonghong Song
c0c852dd18 bpf: Do not mark certain LSM hook arguments as trusted
Martin mentioned that the verifier cannot assume arguments from
LSM hook sk_alloc_security being trusted since after the hook
is called, the sk ref_count is set to 1. This will overwrite
the ref_count changed by the bpf program and may cause ref_count
underflow later on.

I then further checked some other hooks. For example,
for bpf_lsm_file_alloc() hook in fs/file_table.c,

        f->f_cred = get_cred(cred);
        error = security_file_alloc(f);
        if (unlikely(error)) {
                file_free_rcu(&f->f_rcuhead);
                return ERR_PTR(error);
        }

        atomic_long_set(&f->f_count, 1);

The input parameter 'f' to security_file_alloc() cannot be trusted
as well.

Specifically, I investiaged bpf_map/bpf_prog/file/sk/task alloc/free
lsm hooks. Except bpf_map_alloc and task_alloc, arguments for all other
hooks should not be considered as trusted. This may not be a complete
list, but it covers common usage for sk and task.

Fixes: 3f00c52393 ("bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs")
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221203204954.2043348-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 12:59:58 -08:00
Alexei Starovoitov
1910676cc1 Merge branch 'bpf: Handle MEM_RCU type properly'
Yonghong Song says:

====================

Patch set [1] added rcu support for bpf programs. In [1], a rcu
pointer is considered to be trusted and not null. This is actually
not true in some cases. The rcu pointer could be null, and for non-null
rcu pointer, it may have reference count of 0. This small patch set
fixed this problem. Patch 1 is the kernel fix. Patch 2 adjusted
selftests properly. Patch 3 added documentation for newly-introduced
KF_RCU flag.

  [1] https://lore.kernel.org/all/20221124053201.2372298-1-yhs@fb.com/

Changelogs:
  v1 -> v2:
    - rcu ptr could be NULL.
    - non_null_rcu_ptr->rcu_field can be marked as MEM_RCU as well.
    - Adjust the code to avoid existing error message change.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 12:52:40 -08:00
Yonghong Song
f536256498 docs/bpf: Add KF_RCU documentation
Add proper KF_RCU documentation in kfuncs.rst.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221203184613.478967-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 12:52:40 -08:00
Yonghong Song
8723ec22a3 selftests/bpf: Fix rcu_read_lock test with new MEM_RCU semantics
Add MEM_RCU pointer null checking for related tests. Also
modified task_acquire test so it takes a rcu ptr 'ptr' where
'ptr = rcu_ptr->rcu_field'.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221203184607.478314-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 12:52:40 -08:00
Yonghong Song
fca1aa7551 bpf: Handle MEM_RCU type properly
Commit 9bb00b2895 ("bpf: Add kfunc bpf_rcu_read_lock/unlock()")
introduced MEM_RCU and bpf_rcu_read_lock/unlock() support. In that
commit, a rcu pointer is tagged with both MEM_RCU and PTR_TRUSTED
so that it can be passed into kfuncs or helpers as an argument.

Martin raised a good question in [1] such that the rcu pointer,
although being able to accessing the object, might have reference
count of 0. This might cause a problem if the rcu pointer is passed
to a kfunc which expects trusted arguments where ref count should
be greater than 0.

This patch makes the following changes related to MEM_RCU pointer:
  - MEM_RCU pointer might be NULL (PTR_MAYBE_NULL).
  - Introduce KF_RCU so MEM_RCU ptr can be acquired with
    a KF_RCU tagged kfunc which assumes ref count of rcu ptr
    could be zero.
  - For mem access 'b = ptr->a', say 'ptr' is a MEM_RCU ptr, and
    'a' is tagged with __rcu as well. Let us mark 'b' as
    MEM_RCU | PTR_MAYBE_NULL.

 [1] https://lore.kernel.org/bpf/ac70f574-4023-664e-b711-e0d3b18117fd@linux.dev/

Fixes: 9bb00b2895 ("bpf: Add kfunc bpf_rcu_read_lock/unlock()")
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221203184602.477272-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 12:52:40 -08:00
Xin Liu
7068194959 libbpf: Improve usability of libbpf Makefile
Current libbpf Makefile does not contain the help command, which
is inconvenient to use. Similar to the Makefile help command of the
perf, a help command is provided to list the commands supported by
libbpf make and the functions of the commands.

Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221202081738.128513-1-liuxin350@huawei.com
2022-12-02 16:30:34 -08:00
James Hilliard
f16a7aa5c2 selftests/bpf: Add GCC compatible builtins to bpf_legacy.h
The bpf_legacy.h header uses llvm specific load functions, add
GCC compatible variants as well to fix tests using these functions
under GCC.

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221201190939.3230513-1-james.hilliard1@gmail.com
2022-12-02 16:22:28 -08:00
Zheng Yejian
bc067cacb6 bpf, docs: Correct the example of BPF_XOR
Refer to description of BPF_XOR, dst_reg should be used but not src_reg
in the examples.

Fixes: be3193cded ("bpf, docs: Add subsections for ALU and JMP instructions")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221129134558.2757043-1-zhengyejian1@huawei.com
2022-12-02 21:27:32 +01:00
Dave Marchevsky
78b037bd40 selftests/bpf: Validate multiple ref release_on_unlock logic
Modify list_push_pop_multiple to alloc and insert nodes 2-at-a-time.
Without the previous patch's fix, this block of code:

  bpf_spin_lock(lock);
  bpf_list_push_front(head, &f[i]->node);
  bpf_list_push_front(head, &f[i + 1]->node);
  bpf_spin_unlock(lock);

would fail check_reference_leak check as release_on_unlock logic would miss
a ref that should've been released.

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221201183406.1203621-2-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-01 19:38:17 -08:00
Dave Marchevsky
1f82dffc10 bpf: Fix release_on_unlock release logic for multiple refs
Consider a verifier state with three acquired references, all with
release_on_unlock = true:

            idx  0 1 2
  state->refs = [2 4 6]

(with 2, 4, and 6 being the ref ids).

When bpf_spin_unlock is called, process_spin_lock will loop through all
acquired_refs and, for each ref, if it's release_on_unlock, calls
release_reference on it. That function in turn calls
release_reference_state, which removes the reference from state->refs by
swapping the reference state with the last reference state in
refs array and decrements acquired_refs count.

process_spin_lock's loop logic, which is essentially:

  for (i = 0; i < state->acquired_refs; i++) {
    if (!state->refs[i].release_on_unlock)
      continue;
    release_reference(state->refs[i].id);
  }

will fail to release release_on_unlock references which are swapped from
the end. Running this logic on our example demonstrates:

  state->refs = [2 4 6] (start of idx=0 iter)
    release state->refs[0] by swapping w/ state->refs[2]

  state->refs = [6 4]   (start of idx=1)
    release state->refs[1], no need to swap as it's the last idx

  state->refs = [6]     (start of idx=2, loop terminates)

ref_id 6 should have been removed but was skipped.

Fix this by looping from back-to-front, which results in refs that are
candidates for removal being swapped with refs which have already been
examined and kept.

If we modify our initial example such that ref 6 is replaced with ref 7,
which is _not_ release_on_unlock, and loop from the back, we'd see:

  state->refs = [2 4 7] (start of idx=2)

  state->refs = [2 4 7] (start of idx=1)

  state->refs = [2 7]   (start of idx=0, refs 7 and 4 swapped)

  state->refs = [7]     (after idx=0, 7 and 2 swapped, loop terminates)

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Fixes: 534e86bc6c ("bpf: Add 'release on unlock' logic for bpf_list_push_{front,back}")
Link: https://lore.kernel.org/r/20221201183406.1203621-1-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-01 19:38:17 -08:00
Yonghong Song
3144bfa507 bpf: Fix a compilation failure with clang lto build
When building the kernel with clang lto (CONFIG_LTO_CLANG_FULL=y), the
following compilation error will appear:

  $ make LLVM=1 LLVM_IAS=1 -j
  ...
  ld.lld: error: ld-temp.o <inline asm>:26889:1: symbol 'cgroup_storage_map_btf_ids' is already defined
  cgroup_storage_map_btf_ids:;
  ^
  make[1]: *** [/.../bpf-next/scripts/Makefile.vmlinux_o:61: vmlinux.o] Error 1

In local_storage.c, we have
  BTF_ID_LIST_SINGLE(cgroup_storage_map_btf_ids, struct, bpf_local_storage_map)
Commit c4bcfb38a9 ("bpf: Implement cgroup storage available to
non-cgroup-attached bpf progs") added the above identical BTF_ID_LIST_SINGLE
definition in bpf_cgrp_storage.c. With duplicated definitions, llvm linker
complains with lto build.

Also, extracting btf_id of 'struct bpf_local_storage_map' is defined four times
for sk, inode, task and cgrp local storages. Let us define a single global one
with a different name than cgroup_storage_map_btf_ids, which also fixed
the lto compilation error.

Fixes: c4bcfb38a9 ("bpf: Implement cgroup storage available to non-cgroup-attached bpf progs")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221130052147.1591625-1-yhs@fb.com
2022-11-30 17:13:25 -08:00
Pengcheng Yang
89903dcb3c selftests/bpf: Add ingress tests for txmsg with apply_bytes
Currently, the ingress redirect is not covered in "txmsg test apply".

Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/1669718441-2654-5-git-send-email-yangpc@wangsu.com
2022-12-01 01:07:41 +01:00
Pengcheng Yang
9072931f02 bpf, sockmap: Fix data loss caused by using apply_bytes on ingress redirect
Use apply_bytes on ingress redirect, when apply_bytes is less than
the length of msg data, some data may be skipped and lost in
bpf_tcp_ingress().

If there is still data in the scatterlist that has not been consumed,
we cannot move the msg iter.

Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/1669718441-2654-4-git-send-email-yangpc@wangsu.com
2022-12-01 01:07:36 +01:00
Pengcheng Yang
a351d6087b bpf, sockmap: Fix missing BPF_F_INGRESS flag when using apply_bytes
When redirecting, we use sk_msg_to_ingress() to get the BPF_F_INGRESS
flag from the msg->flags. If apply_bytes is used and it is larger than
the current data being processed, sk_psock_msg_verdict() will not be
called when sendmsg() is called again. At this time, the msg->flags is 0,
and we lost the BPF_F_INGRESS flag.

So we need to save the BPF_F_INGRESS flag in sk_psock and use it when
redirection.

Fixes: 8934ce2fd0 ("bpf: sockmap redirect ingress support")
Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/1669718441-2654-3-git-send-email-yangpc@wangsu.com
2022-12-01 01:07:32 +01:00
Pengcheng Yang
7a9841ca02 bpf, sockmap: Fix repeated calls to sock_put() when msg has more_data
In tcp_bpf_send_verdict() redirection, the eval variable is assigned to
__SK_REDIRECT after the apply_bytes data is sent, if msg has more_data,
sock_put() will be called multiple times.

We should reset the eval variable to __SK_NONE every time more_data
starts.

This causes:

IPv4: Attempt to release TCP socket in state 1 00000000b4c925d7
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 5 PID: 4482 at lib/refcount.c:25 refcount_warn_saturate+0x7d/0x110
Modules linked in:
CPU: 5 PID: 4482 Comm: sockhash_bypass Kdump: loaded Not tainted 6.0.0 #1
Hardware name: Red Hat KVM, BIOS 1.11.0-2.el7 04/01/2014
Call Trace:
 <TASK>
 __tcp_transmit_skb+0xa1b/0xb90
 ? __alloc_skb+0x8c/0x1a0
 ? __kmalloc_node_track_caller+0x184/0x320
 tcp_write_xmit+0x22a/0x1110
 __tcp_push_pending_frames+0x32/0xf0
 do_tcp_sendpages+0x62d/0x640
 tcp_bpf_push+0xae/0x2c0
 tcp_bpf_sendmsg_redir+0x260/0x410
 ? preempt_count_add+0x70/0xa0
 tcp_bpf_send_verdict+0x386/0x4b0
 tcp_bpf_sendmsg+0x21b/0x3b0
 sock_sendmsg+0x58/0x70
 __sys_sendto+0xfa/0x170
 ? xfd_validate_state+0x1d/0x80
 ? switch_fpu_return+0x59/0xe0
 __x64_sys_sendto+0x24/0x30
 do_syscall_64+0x37/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: cd9733f5d7 ("tcp_bpf: Fix one concurrency problem in the tcp_bpf_send_verdict function")
Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/1669718441-2654-2-git-send-email-yangpc@wangsu.com
2022-12-01 01:07:21 +01:00
Alexei Starovoitov
c67cae551f bpf: Tighten ptr_to_btf_id checks.
The networking programs typically don't require CAP_PERFMON, but through kfuncs
like bpf_cast_to_kern_ctx() they can access memory through PTR_TO_BTF_ID. In
such case enforce CAP_PERFMON.
Also make sure that only GPL programs can access kernel data structures.
All kfuncs require GPL already.

Also remove allow_ptr_to_map_access. It's the same as allow_ptr_leaks and
different name for the same check only causes confusion.

Fixes: fd264ca020 ("bpf: Add a kfunc to type cast from bpf uapi ctx to kernel ctx")
Fixes: 50c6b8a9ae ("selftests/bpf: Add a test for btf_type_tag "percpu"")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221125220617.26846-1-alexei.starovoitov@gmail.com
2022-11-30 15:33:48 -08:00
Daniel Borkmann
996c060e2b selftests/bpf: Add bench test to arm64 and s390x denylist
BPF CI fails for arm64 and s390x each with the following result:

  [...]
  All error logs:

  serial_test_kprobe_multi_bench_attach:PASS:get_syms 0 nsec
  serial_test_kprobe_multi_bench_attach:PASS:kprobe_multi_empty__open_and_load 0 nsec
  libbpf: prog 'test_kprobe_empty': failed to attach: Operation not supported
  serial_test_kprobe_multi_bench_attach:FAIL:bpf_program__attach_kprobe_multi_opts unexpected error: -95
  #92      kprobe_multi_bench_attach:FAIL
  [...]

Add the test to the deny list.

Fixes: 5b6c7e5c44 ("selftests/bpf: Add attach bench test")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2022-12-01 00:07:30 +01:00
Andrii Nakryiko
f8186bf65a selftests/bpf: Make sure enum-less bpf_enable_stats() API works in C++ mode
Just a simple test to make sure we don't introduce unwanted compiler
warnings and API still supports passing enums as input argument.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221130200013.2997831-2-andrii@kernel.org
2022-11-30 22:56:47 +01:00
Andrii Nakryiko
b42693415b libbpf: Avoid enum forward-declarations in public API in C++ mode
C++ enum forward declarations are fundamentally not compatible with pure
C enum definitions, and so libbpf's use of `enum bpf_stats_type;`
forward declaration in libbpf/bpf.h public API header is causing C++
compilation issues.

More details can be found in [0], but it comes down to C++ supporting
enum forward declaration only with explicitly specified backing type:

  enum bpf_stats_type: int;

In C (and I believe it's a GCC extension also), such forward declaration
is simply:

  enum bpf_stats_type;

Further, in Linux UAPI this enum is defined in pure C way:

enum bpf_stats_type { BPF_STATS_RUN_TIME = 0; }

And even though in both cases backing type is int, which can be
confirmed by looking at DWARF information, for C++ compiler actual enum
definition and forward declaration are incompatible.

To eliminate this problem, for C++ mode define input argument as int,
which makes enum unnecessary in libbpf public header. This solves the
issue and as demonstrated by next patch doesn't cause any unwanted
compiler warnings, at least with default warnings setting.

  [0] https://stackoverflow.com/questions/42766839/c11-enum-forward-causes-underlying-type-mismatch
  [1] Closes: https://github.com/libbpf/libbpf/issues/249

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221130200013.2997831-1-andrii@kernel.org
2022-11-30 22:56:47 +01:00
Martin KaFai Lau
443f216448 selftests/bpf: Avoid pinning prog when attaching to tc ingress in btf_skc_cls_ingress
This patch removes the need to pin prog when attaching to tc ingress
in the btf_skc_cls_ingress test.  Instead, directly use the
bpf_tc_hook_create() and bpf_tc_attach().  The qdisc clsact
will go away together with the netns, so no need to
bpf_tc_hook_destroy().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-8-martin.lau@linux.dev
2022-11-30 22:47:43 +01:00
Martin KaFai Lau
9b6a777397 selftests/bpf: Remove serial from tests using {open,close}_netns
After removing the mount/umount dance from {open,close}_netns()
in the pervious patch, "serial_" can be removed from
the tests using {open,close}_netns().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-7-martin.lau@linux.dev
2022-11-30 22:47:43 +01:00
Martin KaFai Lau
3084097c36 selftests/bpf: Remove the "/sys" mount and umount dance in {open,close}_netns
The previous patches have removed the need to do the mount and umount
dance when switching netns. In particular:
* Avoid remounting /sys/fs/bpf to have a clean start
* Avoid remounting /sys to get a ifindex of a particular netns

This patch can finally remove the mount and umount dance in
{open,close}_netns which is unnecessarily complicated and
error-prone.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-6-martin.lau@linux.dev
2022-11-30 22:47:43 +01:00
Martin KaFai Lau
5dc42a7fc2 selftests/bpf: Avoid pinning bpf prog in the netns_load_bpf() callers
This patch removes the need to pin prog in the remaining tests in
tc_redirect.c by directly using the bpf_tc_hook_create() and
bpf_tc_attach().  The clsact qdisc will go away together with
the test netns, so no need to do bpf_tc_hook_destroy().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-5-martin.lau@linux.dev
2022-11-30 22:47:43 +01:00
Martin KaFai Lau
f1b73577bb selftests/bpf: Avoid pinning bpf prog in the tc_redirect_peer_l3 test
This patch removes the need to pin prog in the tc_redirect_peer_l3
test by directly using the bpf_tc_hook_create() and bpf_tc_attach().
The clsact qdisc will go away together with the test netns, so
no need to do bpf_tc_hook_destroy().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-4-martin.lau@linux.dev
2022-11-30 22:47:42 +01:00
Martin KaFai Lau
57d0863f1d selftests/bpf: Avoid pinning bpf prog in the tc_redirect_dtime test
This patch removes the need to pin prog in the tc_redirect_dtime
test by directly using the bpf_tc_hook_create() and bpf_tc_attach().
The clsact qdisc will go away together with the test netns, so
no need to do bpf_tc_hook_destroy().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-3-martin.lau@linux.dev
2022-11-30 22:47:42 +01:00
Martin KaFai Lau
052c82dcdc selftests/bpf: Use if_nametoindex instead of reading the /sys/net/class/*/ifindex
When switching netns, the setns_by_fd() is doing dances in mount/umounting
the /sys directories.  One reason is the tc_redirect.c test is depending
on the /sys/net/class/*/ifindex instead of using the if_nametoindex().
if_nametoindex() uses ioctl() to get the ifindex.

This patch is to move all /sys/net/class/*/ifindex usages to
if_nametoindex().  The current code checks ifindex >= 0 which is
incorrect.  ifindex > 0 should be checked instead.  This patch also
stores ifindex_veth_src and ifindex_veth_dst since the latter patch
will need them.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-2-martin.lau@linux.dev
2022-11-30 22:47:42 +01:00
Willem de Bruijn
91a7de8560 selftests/net: add csum offload test
Test NIC hardware checksum offload:

- Rx + Tx
- IPv4 + IPv6
- TCP + UDP

Optional features:

- zero checksum 0xFFFF
- checksum disable 0x0000
- transport encap headers
- randomization

See file header for detailed comments.

Expected results differ depending on NIC features:

- CHECKSUM_UNNECESSARY vs CHECKSUM_COMPLETE
- NETIF_F_HW_CSUM (csum_start/csum_off) vs NETIF_F_IP(V6)_CSUM

Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20221128140210.553391-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 21:24:32 -08:00
Jakub Kicinski
5cb0c51fe3 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:

====================
ipsec-next 2022-11-26

1) Remove redundant variable in esp6.
   From Colin Ian King.

2) Update x->lastused for every packet. It was used only for
   outgoing mobile IPv6 packets, but showed to be usefull
   to check if the a SA is still in use in general.
   From Antony Antony.

3) Remove unused variable in xfrm_byidx_resize.
   From Leon Romanovsky.

4) Finalize extack support for xfrm.
   From Sabrina Dubroca.

* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next:
  xfrm: add extack to xfrm_set_spdinfo
  xfrm: add extack to xfrm_alloc_userspi
  xfrm: add extack to xfrm_do_migrate
  xfrm: add extack to xfrm_new_ae and xfrm_replay_verify_len
  xfrm: add extack to xfrm_del_sa
  xfrm: add extack to xfrm_add_sa_expire
  xfrm: a few coding style clean ups
  xfrm: Remove not-used total variable
  xfrm: update x->lastused for every packet
  esp6: remove redundant variable err
====================

Link: https://lore.kernel.org/r/20221126110303.1859238-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:50:51 -08:00
Jakub Kicinski
b2d7b6e9e4 Merge branch 'net-pcs-altera-tse-simplify-and-clean-up-the-driver'
Maxime Chevallier says:

====================
net: pcs: altera-tse: simplify and clean-up the driver

This small series does a bit of code cleanup in the altera TSE pcs
driver, removing unused register definitions, handling 1000BaseX speed
configuration correctly according to the datasheet, and making use of
proper poll_timeout helpers.

No functional change is introduced.
====================

Link: https://lore.kernel.org/r/20221125131801.64234-1-maxime.chevallier@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:29:59 -08:00
Maxime Chevallier
befd851de2 net: pcs: altera-tse: remove unnecessary register definitions
remove unused register definitions, left from the split with the
altera-tse mac driver.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:29:55 -08:00
Maxime Chevallier
b4a7bf9f5b net: pcs: altera-tse: don't set the speed for 1000BaseX
When disabling the SGMII mode bit, the PCS defaults to 1000BaseX mode.
In that mode, we don't need to set the speed since it's always 1000Mbps.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:29:55 -08:00
Maxime Chevallier
d1a0ff5ff9 net: pcs: altera-tse: use read_poll_timeout to wait for reset
Software resets on the TSE PCS don't clear registers, but rather reset
all internal state machines regarding AN, comma detection and
encoding/decoding. Use read_poll_timeout to wait for the reset to clear
instead of manually polling the register.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:29:55 -08:00
Jakub Kicinski
7f0c940be5 Merge branch 'mptcp-msg_fastopen-and-tfo-listener-side-support'
Matthieu Baerts says:

====================
mptcp: MSG_FASTOPEN and TFO listener side support

Before this series, only the initiator of a connection was able to combine
both TCP FastOpen and MPTCP when using TCP_FASTOPEN_CONNECT socket option.

These new patches here add (in theory) the full support of TFO with MPTCP,
which means:

 - MSG_FASTOPEN sendmsg flag support (patch 1/8)
 - TFO support for the listener side (patches 2-5/8)
 - TCP_FASTOPEN socket option (patch 6/8)
 - TCP_FASTOPEN_KEY socket option (patch 7/8)

To support TFO for the server side, a few preparation patches are needed
(patches 2 to 5/8). Some of them were inspired by a previous work from
Benjamin Hesmans.

Note that TFO support with MPTCP has been validated with selftests
(patch 8/8) but also with Packetdrill tests running with a modified
but still very WIP version supporting MPTCP. Both the modified tool
and the tests are available online:

  https://github.com/multipath-tcp/packetdrill/
====================

Link: https://lore.kernel.org/r/20221125222958.958636-1-matthieu.baerts@tessares.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:33 -08:00
Dmytro Shytyi
ca7ae89160 selftests: mptcp: mptfo Initiator/Listener
This patch first adds TFO support in mptcp_connect.c.

This can be enabled via a new option: -o MPTFO.

Once enabled, the TCP_FASTOPEN socket option is enabled for the server
side and a sendto() with MSG_FASTOPEN is used instead of a connect() for
the client side.

Note that the first SYN has a limit of bytes it can carry. In other
words, it is allowed to send less data than the provided one. We then
need to track more status info to properly allow the next sendmsg()
starting from the next part of the data to send the rest.

Also in TFO scenarios, we need to completely spool the partially xmitted
buffer -- and account for that -- before starting sendfile/mmap xmit,
otherwise the relevant tests will fail.

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:26 -08:00
Matthieu Baerts
cb99816cb5 mptcp: add support for TCP_FASTOPEN_KEY sockopt
The goal of this socket option is to set different keys per listener,
see commit 1fba70e5b6 ("tcp: socket option to set TCP fast open key")
for more details about this socket option.

The only thing to do here with MPTCP is to relay the request to the
first subflow like it is already done for the other TCP_FASTOPEN* socket
options.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:26 -08:00
Dmytro Shytyi
4ffb0a0234 mptcp: add TCP_FASTOPEN sock option
The TCP_FASTOPEN socket option is one way for the application to tell
the kernel TFO support has to be enabled for the listener socket.

The only thing to do here with MPTCP is to relay the request to the
first subflow like it is already done for the other TCP_FASTOPEN* socket
options.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:25 -08:00
Dmytro Shytyi
36b122baf6 mptcp: add subflow_v(4,6)_send_synack()
The send_synack() needs to be overridden for MPTCP to support TFO for
two reasons:

- There is not be enough space in the TCP options if the TFO cookie has
  to be added in the SYN+ACK with other options: MSS (4), SACK OK (2),
  Timestamps (10), Window Scale (3+1), TFO (10+2), MP_CAPABLE (12).
  MPTCPv1 specs -- RFC 8684, section B.1 [1] -- suggest to drop the TCP
  timestamps option in this case.

- The data received in the SYN has to be handled: the SKB can be
  dequeued from the subflow sk and transferred to the MPTCP sk. Counters
  need to be updated accordingly and the application can be notified at
  the end because some bytes have been received.

[1] https://www.rfc-editor.org/rfc/rfc8684.html#section-b.1

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:25 -08:00
Dmytro Shytyi
dfc8d06030 mptcp: implement delayed seq generation for passive fastopen
With fastopen in place, the first subflow socket is created before the
MPC handshake completes, and we need to properly initialize the sequence
numbers at MPC ACK reception.

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:25 -08:00
Paolo Abeni
b3ea6b272d mptcp: consolidate initial ack seq generation
Currently the initial ack sequence is generated on demand whenever
it's requested and the remote key is handy. The relevant code is
scattered in different places and can lead to multiple, unneeded,
crypto operations.

This change consolidates the ack sequence generation code in a single
helper, storing the sequence number at the subflow level.

The above additionally saves a few conditional in fast-path and will
simplify the upcoming fast-open implementation.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:25 -08:00