Commit Graph

2330 Commits

Author SHA1 Message Date
Andrii Nakryiko
87ac0d6009 bpf: fix potential 32-bit overflow when accessing ARRAY map element
If BPF array map is bigger than 4GB, element pointer calculation can
overflow because both index and elem_size are u32. Fix this everywhere
by forcing 64-bit multiplication. Extract this formula into separate
small helper and use it consistently in various places.

Speculative-preventing formula utilizing index_mask trick is left as is,
but explicit u64 casts are added in both places.

Fixes: c85d69135a ("bpf: move memory size checks to bpf_map_charge_init()")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220715053146.1291891-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 09:45:34 -07:00
Stanislav Fomichev
3908fcddc6 bpf: fix lsm_cgroup build errors on esoteric configs
This particular ones is about having the following:
 CONFIG_BPF_LSM=y
 # CONFIG_CGROUP_BPF is not set

Also, add __maybe_unused to the args for the !CONFIG_NET cases.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220714185404.3647772-1-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 09:40:41 -07:00
Pu Lehui
3848636b4a bpf: iterators: Build and use lightweight bootstrap version of bpftool
kernel/bpf/preload/iterators use bpftool for vmlinux.h, skeleton, and
static linking only. So we can use lightweight bootstrap version of
bpftool to handle these, and it will be faster.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220714024612.944071-4-pulehui@huawei.com
2022-07-15 12:01:30 -07:00
Ben Dooks
a2a5580fcb bpf: Fix check against plain integer v 'NULL'
When checking with sparse, btf_show_type_value() is causing a
warning about checking integer vs NULL when the macro is passed
a pointer, due to the 'value != 0' check. Stop sparse complaining
about any type-casting by adding a cast to the typeof(value).

This fixes the following sparse warnings:

kernel/bpf/btf.c:2579:17: warning: Using plain integer as NULL pointer
kernel/bpf/btf.c:2581:17: warning: Using plain integer as NULL pointer
kernel/bpf/btf.c:3407:17: warning: Using plain integer as NULL pointer
kernel/bpf/btf.c:3758:9: warning: Using plain integer as NULL pointer

Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220714100322.260467-1-ben.dooks@sifive.com
2022-07-15 09:55:20 -07:00
Alexei Starovoitov
9c7c48d6a1 bpf: Fix subprog names in stack traces.
The commit 7337224fc1 ("bpf: Improve the info.func_info and info.func_info_rec_size behavior")
accidently made bpf_prog_ksym_set_name() conservative for bpf subprograms.
Fixed it so instead of "bpf_prog_tag_F" the stack traces print "bpf_prog_tag_full_subprog_name".

Fixes: 7337224fc1 ("bpf: Improve the info.func_info and info.func_info_rec_size behavior")
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220714211637.17150-1-alexei.starovoitov@gmail.com
2022-07-14 23:43:01 -07:00
Yafang Shao
5002615a37 bpf: Warn on non-preallocated case for BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE is also tracing type, which may
cause unexpected memory allocation if we set BPF_F_NO_PREALLOC. Let's
also warn on it similar as we do in case of BPF_PROG_TYPE_RAW_TRACEPOINT.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220713160936.57488-1-laoar.shao@gmail.com
2022-07-14 22:51:35 +02:00
Joanne Koong
8ab4cdcf03 bpf: Tidy up verifier check_func_arg()
This patch does two things:

1. For matching against the arg type, the match should be against the
base type of the arg type, since the arg type can have different
bpf_type_flags set on it.

2. Uses switch casing to improve readability + efficiency.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Acked-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/r/20220712210603.123791-1-joannelkoong@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-13 14:45:58 -07:00
Yafang Shao
ace2bee839 bpf: Make non-preallocated allocation low priority
GFP_ATOMIC doesn't cooperate well with memcg pressure so far, especially
if we allocate too much GFP_ATOMIC memory. For example, when we set the
memcg limit to limit a non-preallocated bpf memory, the GFP_ATOMIC can
easily break the memcg limit by force charge. So it is very dangerous to
use GFP_ATOMIC in non-preallocated case. One way to make it safe is to
remove __GFP_HIGH from GFP_ATOMIC, IOW, use (__GFP_ATOMIC |
__GFP_KSWAPD_RECLAIM) instead, then it will be limited if we allocate
too much memory. There's a plan to completely remove __GFP_ATOMIC in the
mm side[1], so let's use GFP_NOWAIT instead.

We introduced BPF_F_NO_PREALLOC is because full map pre-allocation is
too memory expensive for some cases. That means removing __GFP_HIGH
doesn't break the rule of BPF_F_NO_PREALLOC, but has the same goal with
it-avoiding issues caused by too much memory. So let's remove it.

This fix can also apply to other run-time allocations, for example, the
allocation in lpm trie, local storage and devmap. So let fix it
consistently over the bpf code

It also fixes a typo in the comment.

[1]. https://lore.kernel.org/linux-mm/163712397076.13692.4727608274002939094@noble.neil.brown.name/

Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Link: https://lore.kernel.org/r/20220709154457.57379-2-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-12 17:44:27 -07:00
Song Liu
1d5f82d9dd bpf, x86: fix freeing of not-finalized bpf_prog_pack
syzbot reported a few issues with bpf_prog_pack [1], [2]. This only happens
with multiple subprogs. In jit_subprogs(), we first call bpf_int_jit_compile()
on each sub program. And then, we call it on each sub program again. jit_data
is not freed in the first call of bpf_int_jit_compile(). Similarly we don't
call bpf_jit_binary_pack_finalize() in the first call of bpf_int_jit_compile().

If bpf_int_jit_compile() failed for one sub program, we will call
bpf_jit_binary_pack_finalize() for this sub program. However, we don't have a
chance to call it for other sub programs. Then we will hit "goto out_free" in
jit_subprogs(), and call bpf_jit_free on some subprograms that haven't got
bpf_jit_binary_pack_finalize() yet.

At this point, bpf_jit_binary_pack_free() is called and the whole 2MB page is
freed erroneously.

Fix this with a custom bpf_jit_free() for x86_64, which calls
bpf_jit_binary_pack_finalize() if necessary. Also, with custom
bpf_jit_free(), bpf_prog_aux->use_bpf_prog_pack is not needed any more,
remove it.

Fixes: 1022a5498f ("bpf, x86_64: Use bpf_jit_binary_pack_alloc")
[1] https://syzkaller.appspot.com/bug?extid=2f649ec6d2eea1495a8f
[2] https://syzkaller.appspot.com/bug?extid=87f65c75f4a72db05445
Reported-by: syzbot+2f649ec6d2eea1495a8f@syzkaller.appspotmail.com
Reported-by: syzbot+87f65c75f4a72db05445@syzkaller.appspotmail.com
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20220706002612.4013790-1-song@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-12 17:33:22 -07:00
Roman Gushchin
4201d9ab3e bpf: reparent bpf maps on memcg offlining
The memory consumed by a bpf map is always accounted to the memory
cgroup of the process which created the map. The map can outlive
the memory cgroup if it's used by processes in other cgroups or
is pinned on bpffs. In this case the map pins the original cgroup
in the dying state.

For other types of objects (slab objects, non-slab kernel allocations,
percpu objects and recently LRU pages) there is a reparenting process
implemented: on cgroup offlining charged objects are getting
reassigned to the parent cgroup. Because all charges and statistics
are fully recursive it's a fairly cheap operation.

For efficiency and consistency with other types of objects, let's do
the same for bpf maps. Fortunately thanks to the objcg API, the
required changes are minimal.

Please, note that individual allocations (slabs, percpu and large
kmallocs) already have the reparenting mechanism. This commit adds
it to the saved map->memcg pointer by replacing it to map->objcg.
Because dying cgroups are not visible for a user and all charges are
recursive, this commit doesn't bring any behavior changes for a user.

v2:
  added a missing const qualifier

Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Link: https://lore.kernel.org/r/20220711162827.184743-1-roman.gushchin@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-12 15:59:12 -07:00
Xu Kuohai
535a57a7ff bpf: Remove is_valid_bpf_tramp_flags()
Before generating bpf trampoline, x86 calls is_valid_bpf_tramp_flags()
to check the input flags. This check is architecture independent.
So, to be consistent with x86, arm64 should also do this check
before generating bpf trampoline.

However, the BPF_TRAMP_F_XXX flags are not used by user code and the
flags argument is almost constant at compile time, so this run time
check is a bit redundant.

Remove is_valid_bpf_tramp_flags() and add some comments to the usage of
BPF_TRAMP_F_XXX flags, as suggested by Alexei.

Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220711150823.2128542-2-xukuohai@huawei.com
2022-07-11 21:04:58 +02:00
Jakub Kicinski
0076cad301 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-07-09

We've added 94 non-merge commits during the last 19 day(s) which contain
a total of 125 files changed, 5141 insertions(+), 6701 deletions(-).

The main changes are:

1) Add new way for performing BTF type queries to BPF, from Daniel Müller.

2) Add inlining of calls to bpf_loop() helper when its function callback is
   statically known, from Eduard Zingerman.

3) Implement BPF TCP CC framework usability improvements, from Jörn-Thorben Hinz.

4) Add LSM flavor for attaching per-cgroup BPF programs to existing LSM
   hooks, from Stanislav Fomichev.

5) Remove all deprecated libbpf APIs in prep for 1.0 release, from Andrii Nakryiko.

6) Add benchmarks around local_storage to BPF selftests, from Dave Marchevsky.

7) AF_XDP sample removal (given move to libxdp) and various improvements around AF_XDP
   selftests, from Magnus Karlsson & Maciej Fijalkowski.

8) Add bpftool improvements for memcg probing and bash completion, from Quentin Monnet.

9) Add arm64 JIT support for BPF-2-BPF coupled with tail calls, from Jakub Sitnicki.

10) Sockmap optimizations around throughput of UDP transmissions which have been
    improved by 61%, from Cong Wang.

11) Rework perf's BPF prologue code to remove deprecated functions, from Jiri Olsa.

12) Fix sockmap teardown path to avoid sleepable sk_psock_stop, from John Fastabend.

13) Fix libbpf's cleanup around legacy kprobe/uprobe on error case, from Chuang Wang.

14) Fix libbpf's bpf_helpers.h to work with gcc for the case of its sec/pragma
    macro, from James Hilliard.

15) Fix libbpf's pt_regs macros for riscv to use a0 for RC register, from Yixun Lan.

16) Fix bpftool to show the name of type BPF_OBJ_LINK, from Yafang Shao.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (94 commits)
  selftests/bpf: Fix xdp_synproxy build failure if CONFIG_NF_CONNTRACK=m/n
  bpf: Correctly propagate errors up from bpf_core_composites_match
  libbpf: Disable SEC pragma macro on GCC
  bpf: Check attach_func_proto more carefully in check_return_code
  selftests/bpf: Add test involving restrict type qualifier
  bpftool: Add support for KIND_RESTRICT to gen min_core_btf command
  MAINTAINERS: Add entry for AF_XDP selftests files
  selftests, xsk: Rename AF_XDP testing app
  bpf, docs: Remove deprecated xsk libbpf APIs description
  selftests/bpf: Add benchmark for local_storage RCU Tasks Trace usage
  libbpf, riscv: Use a0 for RC register
  libbpf: Remove unnecessary usdt_rel_ip assignments
  selftests/bpf: Fix few more compiler warnings
  selftests/bpf: Fix bogus uninitialized variable warning
  bpftool: Remove zlib feature test from Makefile
  libbpf: Cleanup the legacy uprobe_event on failed add/attach_event()
  libbpf: Fix wrong variable used in perf_event_uprobe_open_legacy()
  libbpf: Cleanup the legacy kprobe_event on failed add/attach_event()
  selftests/bpf: Add type match test against kernel's task_struct
  selftests/bpf: Add nested type to type based tests
  ...
====================

Link: https://lore.kernel.org/r/20220708233145.32365-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-09 12:24:16 -07:00
Stanislav Fomichev
d1a6edecc1 bpf: Check attach_func_proto more carefully in check_return_code
Syzkaller reports the following crash:

  RIP: 0010:check_return_code kernel/bpf/verifier.c:10575 [inline]
  RIP: 0010:do_check kernel/bpf/verifier.c:12346 [inline]
  RIP: 0010:do_check_common+0xb3d2/0xd250 kernel/bpf/verifier.c:14610

With the following reproducer:

  bpf$PROG_LOAD_XDP(0x5, &(0x7f00000004c0)={0xd, 0x3, &(0x7f0000000000)=ANY=[@ANYBLOB="1800000000000019000000000000000095"], &(0x7f0000000300)='GPL\x00', 0x0, 0x0, 0x0, 0x0, 0x0, '\x00', 0x0, 0x2b, 0xffffffffffffffff, 0x8, 0x0, 0x0, 0x10, 0x0}, 0x80)

Because we don't enforce expected_attach_type for XDP programs,
we end up in hitting 'if (prog->expected_attach_type == BPF_LSM_CGROUP'
part in check_return_code and follow up with testing
`prog->aux->attach_func_proto->type`, but `prog->aux->attach_func_proto`
is NULL.

Add explicit prog_type check for the "Note, BPF_LSM_CGROUP that
attach ..." condition. Also, don't skip return code check for
LSM/STRUCT_OPS.

The above actually brings an issue with existing selftest which
tries to return EPERM from void inet_csk_clone. Fix the
test (and move called_socket_clone to make sure it's not
incremented in case of an error) and add a new one to explicitly
verify this condition.

Fixes: 69fd337a97 ("bpf: per-cgroup lsm flavor")
Reported-by: syzbot+5cc0730bd4b4d2c5f152@syzkaller.appspotmail.com
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220708175000.2603078-1-sdf@google.com
2022-07-08 23:01:26 +02:00
Jakub Kicinski
83ec88d81a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-07 12:07:37 -07:00
Daniel Müller
ec6209c8d4 bpf, libbpf: Add type match support
This patch adds support for the proposed type match relation to
relo_core where it is shared between userspace and kernel. It plumbs
through both kernel-side and libbpf-side support.

The matching relation is defined as follows (copy from source):
- modifiers and typedefs are stripped (and, hence, effectively ignored)
- generally speaking types need to be of same kind (struct vs. struct, union
  vs. union, etc.)
  - exceptions are struct/union behind a pointer which could also match a
    forward declaration of a struct or union, respectively, and enum vs.
    enum64 (see below)
Then, depending on type:
- integers:
  - match if size and signedness match
- arrays & pointers:
  - target types are recursively matched
- structs & unions:
  - local members need to exist in target with the same name
  - for each member we recursively check match unless it is already behind a
    pointer, in which case we only check matching names and compatible kind
- enums:
  - local variants have to have a match in target by symbolic name (but not
    numeric value)
  - size has to match (but enum may match enum64 and vice versa)
- function pointers:
  - number and position of arguments in local type has to match target
  - for each argument and the return value we recursively check match

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220628160127.607834-5-deso@posteo.net
2022-07-05 21:14:25 -07:00
Daniel Borkmann
3844d153a4 bpf: Fix insufficient bounds propagation from adjust_scalar_min_max_vals
Kuee reported a corner case where the tnum becomes constant after the call
to __reg_bound_offset(), but the register's bounds are not, that is, its
min bounds are still not equal to the register's max bounds.

This in turn allows to leak pointers through turning a pointer register as
is into an unknown scalar via adjust_ptr_min_max_vals().

Before:

  func#0 @0
  0: R1=ctx(off=0,imm=0,umax=0,var_off=(0x0; 0x0)) R10=fp(off=0,imm=0,umax=0,var_off=(0x0; 0x0))
  0: (b7) r0 = 1                        ; R0_w=scalar(imm=1,umin=1,umax=1,var_off=(0x1; 0x0))
  1: (b7) r3 = 0                        ; R3_w=scalar(imm=0,umax=0,var_off=(0x0; 0x0))
  2: (87) r3 = -r3                      ; R3_w=scalar()
  3: (87) r3 = -r3                      ; R3_w=scalar()
  4: (47) r3 |= 32767                   ; R3_w=scalar(smin=-9223372036854743041,umin=32767,var_off=(0x7fff; 0xffffffffffff8000),s32_min=-2147450881)
  5: (75) if r3 s>= 0x0 goto pc+1       ; R3_w=scalar(umin=9223372036854808575,var_off=(0x8000000000007fff; 0x7fffffffffff8000),s32_min=-2147450881,u32_min=32767)
  6: (95) exit

  from 5 to 7: R0=scalar(imm=1,umin=1,umax=1,var_off=(0x1; 0x0)) R1=ctx(off=0,imm=0,umax=0,var_off=(0x0; 0x0)) R3=scalar(umin=32767,umax=9223372036854775807,var_off=(0x7fff; 0x7fffffffffff8000),s32_min=-2147450881) R10=fp(off=0,imm=0,umax=0,var_off=(0x0; 0x0))
  7: (d5) if r3 s<= 0x8000 goto pc+1    ; R3=scalar(umin=32769,umax=9223372036854775807,var_off=(0x7fff; 0x7fffffffffff8000),s32_min=-2147450881,u32_min=32767)
  8: (95) exit

  from 7 to 9: R0=scalar(imm=1,umin=1,umax=1,var_off=(0x1; 0x0)) R1=ctx(off=0,imm=0,umax=0,var_off=(0x0; 0x0)) R3=scalar(umin=32767,umax=32768,var_off=(0x7fff; 0x8000)) R10=fp(off=0,imm=0,umax=0,var_off=(0x0; 0x0))
  9: (07) r3 += -32767                  ; R3_w=scalar(imm=0,umax=1,var_off=(0x0; 0x0))  <--- [*]
  10: (95) exit

What can be seen here is that R3=scalar(umin=32767,umax=32768,var_off=(0x7fff;
0x8000)) after the operation R3 += -32767 results in a 'malformed' constant, that
is, R3_w=scalar(imm=0,umax=1,var_off=(0x0; 0x0)). Intersecting with var_off has
not been done at that point via __update_reg_bounds(), which would have improved
the umax to be equal to umin.

Refactor the tnum <> min/max bounds information flow into a reg_bounds_sync()
helper and use it consistently everywhere. After the fix, bounds have been
corrected to R3_w=scalar(imm=0,umax=0,var_off=(0x0; 0x0)) and thus the register
is regarded as a 'proper' constant scalar of 0.

After:

  func#0 @0
  0: R1=ctx(off=0,imm=0,umax=0,var_off=(0x0; 0x0)) R10=fp(off=0,imm=0,umax=0,var_off=(0x0; 0x0))
  0: (b7) r0 = 1                        ; R0_w=scalar(imm=1,umin=1,umax=1,var_off=(0x1; 0x0))
  1: (b7) r3 = 0                        ; R3_w=scalar(imm=0,umax=0,var_off=(0x0; 0x0))
  2: (87) r3 = -r3                      ; R3_w=scalar()
  3: (87) r3 = -r3                      ; R3_w=scalar()
  4: (47) r3 |= 32767                   ; R3_w=scalar(smin=-9223372036854743041,umin=32767,var_off=(0x7fff; 0xffffffffffff8000),s32_min=-2147450881)
  5: (75) if r3 s>= 0x0 goto pc+1       ; R3_w=scalar(umin=9223372036854808575,var_off=(0x8000000000007fff; 0x7fffffffffff8000),s32_min=-2147450881,u32_min=32767)
  6: (95) exit

  from 5 to 7: R0=scalar(imm=1,umin=1,umax=1,var_off=(0x1; 0x0)) R1=ctx(off=0,imm=0,umax=0,var_off=(0x0; 0x0)) R3=scalar(umin=32767,umax=9223372036854775807,var_off=(0x7fff; 0x7fffffffffff8000),s32_min=-2147450881) R10=fp(off=0,imm=0,umax=0,var_off=(0x0; 0x0))
  7: (d5) if r3 s<= 0x8000 goto pc+1    ; R3=scalar(umin=32769,umax=9223372036854775807,var_off=(0x7fff; 0x7fffffffffff8000),s32_min=-2147450881,u32_min=32767)
  8: (95) exit

  from 7 to 9: R0=scalar(imm=1,umin=1,umax=1,var_off=(0x1; 0x0)) R1=ctx(off=0,imm=0,umax=0,var_off=(0x0; 0x0)) R3=scalar(umin=32767,umax=32768,var_off=(0x7fff; 0x8000)) R10=fp(off=0,imm=0,umax=0,var_off=(0x0; 0x0))
  9: (07) r3 += -32767                  ; R3_w=scalar(imm=0,umax=0,var_off=(0x0; 0x0))  <--- [*]
  10: (95) exit

Fixes: b03c9f9fdc ("bpf/verifier: track signed and unsigned min/max values")
Reported-by: Kuee K1r0a <liulin063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220701124727.11153-2-daniel@iogearbox.net
2022-07-01 12:56:27 -07:00
Daniel Borkmann
a12ca6277e bpf: Fix incorrect verifier simulation around jmp32's jeq/jne
Kuee reported a quirk in the jmp32's jeq/jne simulation, namely that the
register value does not match expectations for the fall-through path. For
example:

Before fix:

  0: R1=ctx(off=0,imm=0) R10=fp0
  0: (b7) r2 = 0                        ; R2_w=P0
  1: (b7) r6 = 563                      ; R6_w=P563
  2: (87) r2 = -r2                      ; R2_w=Pscalar()
  3: (87) r2 = -r2                      ; R2_w=Pscalar()
  4: (4c) w2 |= w6                      ; R2_w=Pscalar(umin=563,umax=4294967295,var_off=(0x233; 0xfffffdcc),s32_min=-2147483085) R6_w=P563
  5: (56) if w2 != 0x8 goto pc+1        ; R2_w=P571  <--- [*]
  6: (95) exit
  R0 !read_ok

After fix:

  0: R1=ctx(off=0,imm=0) R10=fp0
  0: (b7) r2 = 0                        ; R2_w=P0
  1: (b7) r6 = 563                      ; R6_w=P563
  2: (87) r2 = -r2                      ; R2_w=Pscalar()
  3: (87) r2 = -r2                      ; R2_w=Pscalar()
  4: (4c) w2 |= w6                      ; R2_w=Pscalar(umin=563,umax=4294967295,var_off=(0x233; 0xfffffdcc),s32_min=-2147483085) R6_w=P563
  5: (56) if w2 != 0x8 goto pc+1        ; R2_w=P8  <--- [*]
  6: (95) exit
  R0 !read_ok

As can be seen on line 5 for the branch fall-through path in R2 [*] is that
given condition w2 != 0x8 is false, verifier should conclude that r2 = 8 as
upper 32 bit are known to be zero. However, verifier incorrectly concludes
that r2 = 571 which is far off.

The problem is it only marks false{true}_reg as known in the switch for JE/NE
case, but at the end of the function, it uses {false,true}_{64,32}off to
update {false,true}_reg->var_off and they still hold the prior value of
{false,true}_reg->var_off before it got marked as known. The subsequent
__reg_combine_32_into_64() then propagates this old var_off and derives new
bounds. The information between min/max bounds on {false,true}_reg from
setting the register to known const combined with the {false,true}_reg->var_off
based on the old information then derives wrong register data.

Fix it by detangling the BPF_JEQ/BPF_JNE cases and updating relevant
{false,true}_{64,32}off tnums along with the register marking to known
constant.

Fixes: 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Reported-by: Kuee K1r0a <liulin063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220701124727.11153-1-daniel@iogearbox.net
2022-07-01 12:56:27 -07:00
Stanislav Fomichev
9113d7e48e bpf: expose bpf_{g,s}etsockopt to lsm cgroup
I don't see how to make it nice without introducing btf id lists
for the hooks where these helpers are allowed. Some LSM hooks
work on the locked sockets, some are triggering early and
don't grab any locks, so have two lists for now:

1. LSM hooks which trigger under socket lock - minority of the hooks,
   but ideal case for us, we can expose existing BTF-based helpers
2. LSM hooks which trigger without socket lock, but they trigger
   early in the socket creation path where it should be safe to
   do setsockopt without any locks
3. The rest are prohibited. I'm thinking that this use-case might
   be a good gateway to sleeping lsm cgroup hooks in the future.
   We can either expose lock/unlock operations (and add tracking
   to the verifier) or have another set of bpf_setsockopt
   wrapper that grab the locks and might sleep.

Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-7-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29 13:21:52 -07:00
Stanislav Fomichev
b79c9fc955 bpf: implement BPF_PROG_QUERY for BPF_LSM_CGROUP
We have two options:
1. Treat all BPF_LSM_CGROUP the same, regardless of attach_btf_id
2. Treat BPF_LSM_CGROUP+attach_btf_id as a separate hook point

I was doing (2) in the original patch, but switching to (1) here:

* bpf_prog_query returns all attached BPF_LSM_CGROUP programs
regardless of attach_btf_id
* attach_btf_id is exported via bpf_prog_info

Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-6-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29 13:21:52 -07:00
Stanislav Fomichev
c0e19f2c9a bpf: minimize number of allocated lsm slots per program
Previous patch adds 1:1 mapping between all 211 LSM hooks
and bpf_cgroup program array. Instead of reserving a slot per
possible hook, reserve 10 slots per cgroup for lsm programs.
Those slots are dynamically allocated on demand and reclaimed.

struct cgroup_bpf {
	struct bpf_prog_array *    effective[33];        /*     0   264 */
	/* --- cacheline 4 boundary (256 bytes) was 8 bytes ago --- */
	struct hlist_head          progs[33];            /*   264   264 */
	/* --- cacheline 8 boundary (512 bytes) was 16 bytes ago --- */
	u8                         flags[33];            /*   528    33 */

	/* XXX 7 bytes hole, try to pack */

	struct list_head           storages;             /*   568    16 */
	/* --- cacheline 9 boundary (576 bytes) was 8 bytes ago --- */
	struct bpf_prog_array *    inactive;             /*   584     8 */
	struct percpu_ref          refcnt;               /*   592    16 */
	struct work_struct         release_work;         /*   608    72 */

	/* size: 680, cachelines: 11, members: 7 */
	/* sum members: 673, holes: 1, sum holes: 7 */
	/* last cacheline: 40 bytes */
};

Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-5-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29 13:21:52 -07:00
Stanislav Fomichev
69fd337a97 bpf: per-cgroup lsm flavor
Allow attaching to lsm hooks in the cgroup context.

Attaching to per-cgroup LSM works exactly like attaching
to other per-cgroup hooks. New BPF_LSM_CGROUP is added
to trigger new mode; the actual lsm hook we attach to is
signaled via existing attach_btf_id.

For the hooks that have 'struct socket' or 'struct sock' as its first
argument, we use the cgroup associated with that socket. For the rest,
we use 'current' cgroup (this is all on default hierarchy == v2 only).
Note that for some hooks that work on 'struct sock' we still
take the cgroup from 'current' because some of them work on the socket
that hasn't been properly initialized yet.

Behind the scenes, we allocate a shim program that is attached
to the trampoline and runs cgroup effective BPF programs array.
This shim has some rudimentary ref counting and can be shared
between several programs attaching to the same lsm hook from
different cgroups.

Note that this patch bloats cgroup size because we add 211
cgroup_bpf_attach_type(s) for simplicity sake. This will be
addressed in the subsequent patch.

Also note that we only add non-sleepable flavor for now. To enable
sleepable use-cases, bpf_prog_run_array_cg has to grab trace rcu,
shim programs have to be freed via trace rcu, cgroup_bpf.effective
should be also trace-rcu-managed + maybe some other changes that
I'm not aware of.

Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-4-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29 13:21:51 -07:00
Stanislav Fomichev
00442143a2 bpf: convert cgroup_bpf.progs to hlist
This lets us reclaim some space to be used by new cgroup lsm slots.

Before:
struct cgroup_bpf {
	struct bpf_prog_array *    effective[23];        /*     0   184 */
	/* --- cacheline 2 boundary (128 bytes) was 56 bytes ago --- */
	struct list_head           progs[23];            /*   184   368 */
	/* --- cacheline 8 boundary (512 bytes) was 40 bytes ago --- */
	u32                        flags[23];            /*   552    92 */

	/* XXX 4 bytes hole, try to pack */

	/* --- cacheline 10 boundary (640 bytes) was 8 bytes ago --- */
	struct list_head           storages;             /*   648    16 */
	struct bpf_prog_array *    inactive;             /*   664     8 */
	struct percpu_ref          refcnt;               /*   672    16 */
	struct work_struct         release_work;         /*   688    32 */

	/* size: 720, cachelines: 12, members: 7 */
	/* sum members: 716, holes: 1, sum holes: 4 */
	/* last cacheline: 16 bytes */
};

After:
struct cgroup_bpf {
	struct bpf_prog_array *    effective[23];        /*     0   184 */
	/* --- cacheline 2 boundary (128 bytes) was 56 bytes ago --- */
	struct hlist_head          progs[23];            /*   184   184 */
	/* --- cacheline 5 boundary (320 bytes) was 48 bytes ago --- */
	u8                         flags[23];            /*   368    23 */

	/* XXX 1 byte hole, try to pack */

	/* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */
	struct list_head           storages;             /*   392    16 */
	struct bpf_prog_array *    inactive;             /*   408     8 */
	struct percpu_ref          refcnt;               /*   416    16 */
	struct work_struct         release_work;         /*   432    72 */

	/* size: 504, cachelines: 8, members: 7 */
	/* sum members: 503, holes: 1, sum holes: 1 */
	/* last cacheline: 56 bytes */
};

Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-3-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29 13:21:51 -07:00
Stanislav Fomichev
af3f413400 bpf: add bpf_func_t and trampoline helpers
I'll be adding lsm cgroup specific helpers that grab
trampoline mutex.

No functional changes.

Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-2-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29 13:21:51 -07:00
Daniel Müller
fd75733da2 bpf: Merge "types_are_compat" logic into relo_core.c
BPF type compatibility checks (bpf_core_types_are_compat()) are
currently duplicated between kernel and user space. That's a historical
artifact more than intentional doing and can lead to subtle bugs where
one implementation is adjusted but another is forgotten.

That happened with the enum64 work, for example, where the libbpf side
was changed (commit 23b2a3a8f6 ("libbpf: Add enum64 relocation
support")) to use the btf_kind_core_compat() helper function but the
kernel side was not (commit 6089fb325c ("bpf: Add btf enum64
support")).

This patch addresses both the duplication issue, by merging both
implementations and moving them into relo_core.c, and fixes the alluded
to kind check (by giving preference to libbpf's already adjusted logic).

For discussion of the topic, please refer to:
https://lore.kernel.org/bpf/CAADnVQKbWR7oarBdewgOBZUPzryhRYvEbkhyPJQHHuxq=0K1gw@mail.gmail.com/T/#mcc99f4a33ad9a322afaf1b9276fb1f0b7add9665

Changelog:
v1 -> v2:
- limited libbpf recursion limit to 32
- changed name to __bpf_core_types_are_compat
- included warning previously present in libbpf version
- merged kernel and user space changes into a single patch

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220623182934.2582827-1-deso@posteo.net
2022-06-24 14:15:37 -07:00
Eduard Zingerman
fb4e3b33e3 bpf: Fix for use-after-free bug in inline_bpf_loop
As reported by Dan Carpenter, the following statements in inline_bpf_loop()
might cause a use-after-free bug:

  struct bpf_prog *new_prog;
  // ...
  new_prog = bpf_patch_insn_data(env, position, insn_buf, *cnt);
  // ...
  env->prog->insnsi[call_insn_offset].imm = callback_offset;

The bpf_patch_insn_data() might free the memory used by env->prog.

Fixes: 1ade237119 ("bpf: Inline calls to bpf_loop when callback is known")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220624020613.548108-2-eddyz87@gmail.com
2022-06-24 16:50:39 +02:00
Simon Wang
395e942d34 bpf: Replace hard-coded 0 with BPF_K in check_alu_op
Enhance readability a bit.

Signed-off-by: Simon Wang <wangchuanguo@inspur.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220622031923.65692-1-wangchuanguo@inspur.com
2022-06-24 15:40:42 +02:00
Jakub Kicinski
93817be8b6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-23 12:33:24 -07:00
Jörn-Thorben Hinz
9f0265e921 bpf: Require only one of cong_avoid() and cong_control() from a TCP CC
Remove the check for required and optional functions in a struct
tcp_congestion_ops from bpf_tcp_ca.c. Rely on
tcp_register_congestion_control() to reject a BPF CC that does not
implement all required functions, as it will do for a non-BPF CC.

When a CC implements tcp_congestion_ops.cong_control(), the alternate
cong_avoid() is not in use in the TCP stack. Previously, a BPF CC was
still forced to implement cong_avoid() as a no-op since it was
non-optional in bpf_tcp_ca.c.

Signed-off-by: Jörn-Thorben Hinz <jthinz@mailbox.tu-berlin.de>
Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220622191227.898118-3-jthinz@mailbox.tu-berlin.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-23 09:49:57 -07:00
Tony Ambardar
95acd8817e bpf, x64: Add predicate for bpf2bpf with tailcalls support in JIT
The BPF core/verifier is hard-coded to permit mixing bpf2bpf and tail
calls for only x86-64. Change the logic to instead rely on a new weak
function 'bool bpf_jit_supports_subprog_tailcalls(void)', which a capable
JIT backend can override.

Update the x86-64 eBPF JIT to reflect this.

Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com>
[jakub: drop MIPS bits and tweak patch subject]
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220617105735.733938-2-jakub@cloudflare.com
2022-06-21 18:52:04 +02:00
Eduard Zingerman
1ade237119 bpf: Inline calls to bpf_loop when callback is known
Calls to `bpf_loop` are replaced with direct loops to avoid
indirection. E.g. the following:

  bpf_loop(10, foo, NULL, 0);

Is replaced by equivalent of the following:

  for (int i = 0; i < 10; ++i)
    foo(i, NULL);

This transformation could be applied when:
- callback is known and does not change during program execution;
- flags passed to `bpf_loop` are always zero.

Inlining logic works as follows:

- During execution simulation function `update_loop_inline_state`
  tracks the following information for each `bpf_loop` call
  instruction:
  - is callback known and constant?
  - are flags constant and zero?
- Function `optimize_bpf_loop` increases stack depth for functions
  where `bpf_loop` calls can be inlined and invokes `inline_bpf_loop`
  to apply the inlining. The additional stack space is used to spill
  registers R6, R7 and R8. These registers are used as loop counter,
  loop maximal bound and callback context parameter;

Measurements using `benchs/run_bench_bpf_loop.sh` inside QEMU / KVM on
i7-4710HQ CPU show a drop in latency from 14 ns/op to 2 ns/op.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/r/20220620235344.569325-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-20 17:40:51 -07:00
Jakub Kicinski
9fb424c4c2 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-06-17

We've added 72 non-merge commits during the last 15 day(s) which contain
a total of 92 files changed, 4582 insertions(+), 834 deletions(-).

The main changes are:

1) Add 64 bit enum value support to BTF, from Yonghong Song.

2) Implement support for sleepable BPF uprobe programs, from Delyan Kratunov.

3) Add new BPF helpers to issue and check TCP SYN cookies without binding to a
   socket especially useful in synproxy scenarios, from Maxim Mikityanskiy.

4) Fix libbpf's internal USDT address translation logic for shared libraries as
   well as uprobe's symbol file offset calculation, from Andrii Nakryiko.

5) Extend libbpf to provide an API for textual representation of the various
   map/prog/attach/link types and use it in bpftool, from Daniel Müller.

6) Provide BTF line info for RV64 and RV32 JITs, and fix a put_user bug in the
   core seen in 32 bit when storing BPF function addresses, from Pu Lehui.

7) Fix libbpf's BTF pointer size guessing by adding a list of various aliases
   for 'long' types, from Douglas Raillard.

8) Fix bpftool to readd setting rlimit since probing for memcg-based accounting
   has been unreliable and caused a regression on COS, from Quentin Monnet.

9) Fix UAF in BPF cgroup's effective program computation triggered upon BPF link
   detachment, from Tadeusz Struk.

10) Fix bpftool build bootstrapping during cross compilation which was pointing
    to the wrong AR process, from Shahab Vahedi.

11) Fix logic bug in libbpf's is_pow_of_2 implementation, from Yuze Chi.

12) BPF hash map optimization to avoid grabbing spinlocks of all CPUs when there
    is no free element. Also add a benchmark as reproducer, from Feng Zhou.

13) Fix bpftool's codegen to bail out when there's no BTF, from Michael Mullin.

14) Various minor cleanup and improvements all over the place.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits)
  bpf: Fix bpf_skc_lookup comment wrt. return type
  bpf: Fix non-static bpf_func_proto struct definitions
  selftests/bpf: Don't force lld on non-x86 architectures
  selftests/bpf: Add selftests for raw syncookie helpers in TC mode
  bpf: Allow the new syncookie helpers to work with SKBs
  selftests/bpf: Add selftests for raw syncookie helpers
  bpf: Add helpers to issue and check SYN cookies in XDP
  bpf: Allow helpers to accept pointers with a fixed size
  bpf: Fix documentation of th_len in bpf_tcp_{gen,check}_syncookie
  selftests/bpf: add tests for sleepable (uk)probes
  libbpf: add support for sleepable uprobe programs
  bpf: allow sleepable uprobe programs to attach
  bpf: implement sleepable uprobes by chaining gps
  bpf: move bpf_prog to bpf.h
  libbpf: Fix internal USDT address translation logic for shared libraries
  samples/bpf: Check detach prog exist or not in xdp_fwd
  selftests/bpf: Avoid skipping certain subtests
  selftests/bpf: Fix test_varlen verification failure with latest llvm
  bpftool: Do not check return value from libbpf_set_strict_mode()
  Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"
  ...
====================

Link: https://lore.kernel.org/r/20220617220836.7373-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-17 19:35:19 -07:00
Joanne Koong
dc368e1c65 bpf: Fix non-static bpf_func_proto struct definitions
This patch does two things:

1) Marks the dynptr bpf_func_proto structs that were added in [1]
   as static, as pointed out by the kernel test robot in [2].

2) There are some bpf_func_proto structs marked as extern which can
   instead be statically defined.

  [1] https://lore.kernel.org/bpf/20220523210712.3641569-1-joannelkoong@gmail.com/
  [2] https://lore.kernel.org/bpf/62ab89f2.Pko7sI08RAKdF8R6%25lkp@intel.com/

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220616225407.1878436-1-joannelkoong@gmail.com
2022-06-17 16:00:51 +02:00
Maxim Mikityanskiy
508362ac66 bpf: Allow helpers to accept pointers with a fixed size
Before this commit, the BPF verifier required ARG_PTR_TO_MEM arguments
to be followed by ARG_CONST_SIZE holding the size of the memory region.
The helpers had to check that size in runtime.

There are cases where the size expected by a helper is a compile-time
constant. Checking it in runtime is an unnecessary overhead and waste of
BPF registers.

This commit allows helpers to accept pointers to memory without the
corresponding ARG_CONST_SIZE, given that they define the memory region
size in struct bpf_func_proto and use ARG_PTR_TO_FIXED_SIZE_MEM type.

arg_size is unionized with arg_btf_id to reduce the kernel image size,
and it's valid because they are used by different argument types.

Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20220615134847.3753567-3-maximmi@nvidia.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-16 21:20:29 -07:00
Delyan Kratunov
64ad7556c7 bpf: allow sleepable uprobe programs to attach
uprobe and kprobe programs have the same program type, KPROBE, which is
currently not allowed to load sleepable programs.

To avoid adding a new UPROBE type, instead allow sleepable KPROBE
programs to load and defer the is-it-actually-a-uprobe-program check
to attachment time, where there's already validation of the
corresponding perf_event.

A corollary of this patch is that you can now load a sleepable kprobe
program but cannot attach it.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Delyan Kratunov <delyank@fb.com>
Link: https://lore.kernel.org/r/fcd44a7cd204f372f6bb03ef794e829adeaef299.1655248076.git.delyank@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-16 19:27:29 -07:00
Delyan Kratunov
8c7dcb84e3 bpf: implement sleepable uprobes by chaining gps
uprobes work by raising a trap, setting a task flag from within the
interrupt handler, and processing the actual work for the uprobe on the
way back to userspace. As a result, uprobe handlers already execute in a
might_fault/_sleep context. The primary obstacle to sleepable bpf uprobe
programs is therefore on the bpf side.

Namely, the bpf_prog_array attached to the uprobe is protected by normal
rcu. In order for uprobe bpf programs to become sleepable, it has to be
protected by the tasks_trace rcu flavor instead (and kfree() called after
a corresponding grace period).

Therefore, the free path for bpf_prog_array now chains a tasks_trace and
normal grace periods one after the other.

Users who iterate under tasks_trace read section would
be safe, as would users who iterate under normal read sections (from
non-sleepable locations).

The downside is that the tasks_trace latency affects all perf_event-attached
bpf programs (and not just uprobe ones). This is deemed safe given the
possible attach rates for kprobe/uprobe/tp programs.

Separately, non-sleepable programs need access to dynamically sized
rcu-protected maps, so bpf_run_prog_array_sleepables now conditionally takes
an rcu read section, in addition to the overarching tasks_trace section.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Link: https://lore.kernel.org/r/ce844d62a2fd0443b08c5ab02e95bc7149f9aeb1.1655248076.git.delyank@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-16 19:27:29 -07:00
Kumar Kartikeya Dwivedi
d1a374a1ae bpf: Limit maximum modifier chain length in btf_check_type_tags
On processing a module BTF of module built for an older kernel, we might
sometimes find that some type points to itself forming a loop. If such a
type is a modifier, btf_check_type_tags's while loop following modifier
chain will be caught in an infinite loop.

Fix this by defining a maximum chain length and bailing out if we spin
any longer than that.

Fixes: eb596b0905 ("bpf: Ensure type tags precede modifiers in BTF")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220615042151.2266537-1-memxor@gmail.com
2022-06-15 19:32:12 +02:00
Feng Zhou
54a9c3a42d bpf: avoid grabbing spin_locks of all cpus when no free elems
This patch use head->first in pcpu_freelist_head to check freelist
having free or not. If having, grab spin_lock, or check next cpu's
freelist.

Before patch: hash_map performance
./map_perf_test 1
0:hash_map_perf pre-alloc 1043397 events per sec
...
The average of the test results is around 1050000 events per sec.

hash_map the worst: no free
./run_bench_bpf_hashmap_full_update.sh
Setting up benchmark 'bpf-hashmap-ful-update'...
Benchmark 'bpf-hashmap-ful-update' started.
1:hash_map_full_perf 15687 events per sec
...
The average of the test results is around 16000 events per sec.

ftrace trace:
0)               |  htab_map_update_elem() {
0)               |      __pcpu_freelist_pop() {
0)               |        _raw_spin_lock()
0)               |        _raw_spin_unlock()
0)               |        ...
0) + 25.188 us   |      }
0) + 28.439 us   |  }

The test machine is 16C, trying to get spin_lock 17 times, in addition
to 16c, there is an extralist.

after patch: hash_map performance
./map_perf_test 1
0:hash_map_perf pre-alloc 1053298 events per sec
...
The average of the test results is around 1050000 events per sec.

hash_map worst: no free
./run_bench_bpf_hashmap_full_update.sh
Setting up benchmark 'bpf-hashmap-ful-update'...
Benchmark 'bpf-hashmap-ful-update' started.
1:hash_map_full_perf 555830 events per sec
...
The average of the test results is around 550000 events per sec.

ftrace trace:
0)               |  htab_map_update_elem() {
0)               |    alloc_htab_elem() {
0)   0.586 us    |      __pcpu_freelist_pop();
0)   0.945 us    |    }
0)   8.669 us    |  }

It can be seen that after adding this patch, the map performance is
almost not degraded, and when free=0, first check head->first instead of
directly acquiring spin_lock.

Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Feng Zhou <zhoufeng.zf@bytedance.com>
Link: https://lore.kernel.org/r/20220610023308.93798-2-zhoufeng.zf@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-11 14:25:35 -07:00
Toke Høiland-Jørgensen
f858c2b2ca bpf: Fix calling global functions from BPF_PROG_TYPE_EXT programs
The verifier allows programs to call global functions as long as their
argument types match, using BTF to check the function arguments. One of the
allowed argument types to such global functions is PTR_TO_CTX; however the
check for this fails on BPF_PROG_TYPE_EXT functions because the verifier
uses the wrong type to fetch the vmlinux BTF ID for the program context
type. This failure is seen when an XDP program is loaded using
libxdp (which loads it as BPF_PROG_TYPE_EXT and attaches it to a global XDP
type program).

Fix the issue by passing in the target program type instead of the
BPF_PROG_TYPE_EXT type to bpf_prog_get_ctx() when checking function
argument compatibility.

The first Fixes tag refers to the latest commit that touched the code in
question, while the second one points to the code that first introduced
the global function call verification.

v2:
- Use resolve_prog_type()

Fixes: 3363bd0cfb ("bpf: Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support")
Fixes: 51c39bb1d5 ("bpf: Introduce function-by-function verification")
Reported-by: Simon Sundberg <simon.sundberg@kau.se>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20220606075253.28422-1-toke@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-07 10:41:20 -07:00
Yonghong Song
6089fb325c bpf: Add btf enum64 support
Currently, BTF only supports upto 32bit enum value with BTF_KIND_ENUM.
But in kernel, some enum indeed has 64bit values, e.g.,
in uapi bpf.h, we have
  enum {
        BPF_F_INDEX_MASK                = 0xffffffffULL,
        BPF_F_CURRENT_CPU               = BPF_F_INDEX_MASK,
        BPF_F_CTXLEN_MASK               = (0xfffffULL << 32),
  };
In this case, BTF_KIND_ENUM will encode the value of BPF_F_CTXLEN_MASK
as 0, which certainly is incorrect.

This patch added a new btf kind, BTF_KIND_ENUM64, which permits
64bit value to cover the above use case. The BTF_KIND_ENUM64 has
the following three fields followed by the common type:
  struct bpf_enum64 {
    __u32 nume_off;
    __u32 val_lo32;
    __u32 val_hi32;
  };
Currently, btf type section has an alignment of 4 as all element types
are u32. Representing the value with __u64 will introduce a pad
for bpf_enum64 and may also introduce misalignment for the 64bit value.
Hence, two members of val_hi32 and val_lo32 are chosen to avoid these issues.

The kflag is also introduced for BTF_KIND_ENUM and BTF_KIND_ENUM64
to indicate whether the value is signed or unsigned. The kflag intends
to provide consistent output of BTF C fortmat with the original
source code. For example, the original BTF_KIND_ENUM bit value is 0xffffffff.
The format C has two choices, printing out 0xffffffff or -1 and current libbpf
prints out as unsigned value. But if the signedness is preserved in btf,
the value can be printed the same as the original source code.
The kflag value 0 means unsigned values, which is consistent to the default
by libbpf and should also cover most cases as well.

The new BTF_KIND_ENUM64 is intended to support the enum value represented as
64bit value. But it can represent all BTF_KIND_ENUM values as well.
The compiler ([1]) and pahole will generate BTF_KIND_ENUM64 only if the value has
to be represented with 64 bits.

In addition, a static inline function btf_kind_core_compat() is introduced which
will be used later when libbpf relo_core.c changed. Here the kernel shares the
same relo_core.c with libbpf.

  [1] https://reviews.llvm.org/D124641

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220607062600.3716578-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-07 10:20:42 -07:00
Tadeusz Struk
4c46091ee9 bpf: Fix KASAN use-after-free Read in compute_effective_progs
Syzbot found a Use After Free bug in compute_effective_progs().
The reproducer creates a number of BPF links, and causes a fault
injected alloc to fail, while calling bpf_link_detach on them.
Link detach triggers the link to be freed by bpf_link_free(),
which calls __cgroup_bpf_detach() and update_effective_progs().
If the memory allocation in this function fails, the function restores
the pointer to the bpf_cgroup_link on the cgroup list, but the memory
gets freed just after it returns. After this, every subsequent call to
update_effective_progs() causes this already deallocated pointer to be
dereferenced in prog_list_length(), and triggers KASAN UAF error.

To fix this issue don't preserve the pointer to the prog or link in the
list, but remove it and replace it with a dummy prog without shrinking
the table. The subsequent call to __cgroup_bpf_detach() or
__cgroup_bpf_detach() will correct it.

Fixes: af6eea5743 ("bpf: Implement bpf_link-based cgroup BPF program attachment")
Reported-by: <syzbot+f264bffdfbd5614f3bb2@syzkaller.appspotmail.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://syzkaller.appspot.com/bug?id=8ebf179a95c2a2670f7cf1ba62429ec044369db4
Link: https://lore.kernel.org/bpf/20220517180420.87954-1-tadeusz.struk@linaro.org
2022-06-02 16:26:47 -07:00
Pu Lehui
cc1685546d bpf: Correct the comment about insn_to_jit_off
The insn_to_jit_off passed to bpf_prog_fill_jited_linfo should be the
first byte of the next instruction, or the byte off to the end of the
current instruction.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220530092815.1112406-4-pulehui@huawei.com
2022-06-02 16:26:06 -07:00
Pu Lehui
2cd0085227 bpf: Unify data extension operation of jited_ksyms and jited_linfo
We found that 32-bit environment can not print BPF line info due to a data
inconsistency between jited_ksyms[0] and jited_linfo[0].

For example:

  jited_kyms[0] = 0xb800067c, jited_linfo[0] = 0xffffffffb800067c

We know that both of them store BPF func address, but due to the different
data extension operations when extended to u64, they may not be the same.
We need to unify the data extension operations of them.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/CAEf4BzZ-eDcdJZgJ+Np7Y=V-TVjDDvOMqPwzKjyWrh=i5juv4w@mail.gmail.com
Link: https://lore.kernel.org/bpf/20220530092815.1112406-2-pulehui@huawei.com
2022-06-02 16:25:57 -07:00
Linus Torvalds
58f9d52ff6 Networking fixes for 5.19-rc1, including fixes from bpf, and netfilter.
Current release - new code bugs:
 
  - af_packet: make sure to pull the MAC header, avoid skb panic in GSO
 
  - ptp_clockmatrix: fix inverted logic in is_single_shot()
 
  - netfilter: flowtable: fix missing FLOWI_FLAG_ANYSRC flag
 
  - dt-bindings: net: adin: fix adi,phy-output-clock description syntax
 
  - wifi: iwlwifi: pcie: rename CAUSE macro, avoid MIPS build warning
 
 Previous releases - regressions:
 
  - Revert "net: af_key: add check for pfkey_broadcast in function
    pfkey_process"
 
  - tcp: fix tcp_mtup_probe_success vs wrong snd_cwnd
 
  - nf_tables: disallow non-stateful expression in sets earlier
 
  - nft_limit: clone packet limits' cost value
 
  - nf_tables: double hook unregistration in netns path
 
  - ping6: fix ping -6 with interface name
 
 Previous releases - always broken:
 
  - sched: fix memory barriers to prevent skbs from getting stuck
    in lockless qdiscs
 
  - neigh: set lower cap for neigh_managed_work rearming, avoid
    constantly scheduling the probe work
 
  - bpf: fix probe read error on big endian in ___bpf_prog_run()
 
  - amt: memory leak and error handling fixes
 
 Misc:
 
  - ipv6: expand & rename accept_unsolicited_na to accept_untracked_na
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Including fixes from bpf and netfilter.

  Current release - new code bugs:

   - af_packet: make sure to pull the MAC header, avoid skb panic in GSO

   - ptp_clockmatrix: fix inverted logic in is_single_shot()

   - netfilter: flowtable: fix missing FLOWI_FLAG_ANYSRC flag

   - dt-bindings: net: adin: fix adi,phy-output-clock description syntax

   - wifi: iwlwifi: pcie: rename CAUSE macro, avoid MIPS build warning

  Previous releases - regressions:

   - Revert "net: af_key: add check for pfkey_broadcast in function
     pfkey_process"

   - tcp: fix tcp_mtup_probe_success vs wrong snd_cwnd

   - nf_tables: disallow non-stateful expression in sets earlier

   - nft_limit: clone packet limits' cost value

   - nf_tables: double hook unregistration in netns path

   - ping6: fix ping -6 with interface name

  Previous releases - always broken:

   - sched: fix memory barriers to prevent skbs from getting stuck in
     lockless qdiscs

   - neigh: set lower cap for neigh_managed_work rearming, avoid
     constantly scheduling the probe work

   - bpf: fix probe read error on big endian in ___bpf_prog_run()

   - amt: memory leak and error handling fixes

  Misc:

   - ipv6: expand & rename accept_unsolicited_na to accept_untracked_na"

* tag 'net-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (80 commits)
  net/af_packet: make sure to pull mac header
  net: add debug info to __skb_pull()
  net: CONFIG_DEBUG_NET depends on CONFIG_NET
  stmmac: intel: Add RPL-P PCI ID
  net: stmmac: use dev_err_probe() for reporting mdio bus registration failure
  tipc: check attribute length for bearer name
  ice: fix access-beyond-end in the switch code
  nfp: remove padding in nfp_nfdk_tx_desc
  ax25: Fix ax25 session cleanup problems
  net: usb: qmi_wwan: Add support for Cinterion MV31 with new baseline
  sfc/siena: fix wrong tx channel offset with efx_separate_tx_channels
  sfc/siena: fix considering that all channels have TX queues
  socket: Don't use u8 type in uapi socket.h
  net/sched: act_api: fix error code in tcf_ct_flow_table_fill_tuple_ipv6()
  net: ping6: Fix ping -6 with interface name
  macsec: fix UAF bug for real_dev
  octeontx2-af: fix error code in is_valid_offset()
  wifi: mac80211: fix use-after-free in chanctx code
  bonding: guard ns_targets by CONFIG_IPV6
  tcp: tcp_rtx_synack() can be called from process context
  ...
2022-06-02 12:50:16 -07:00
Menglong Dong
caff1fa411 bpf: Fix probe read error in ___bpf_prog_run()
I think there is something wrong with BPF_PROBE_MEM in ___bpf_prog_run()
in big-endian machine. Let's make a test and see what will happen if we
want to load a 'u16' with BPF_PROBE_MEM.

Let's make the src value '0x0001', the value of dest register will become
0x0001000000000000, as the value will be loaded to the first 2 byte of
DST with following code:

  bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) (SRC + insn->off));

Obviously, the value in DST is not correct. In fact, we can compare
BPF_PROBE_MEM with LDX_MEM_H:

  DST = *(SIZE *)(unsigned long) (SRC + insn->off);

If the memory load is done by LDX_MEM_H, the value in DST will be 0x1 now.

And I think this error results in the test case 'test_bpf_sk_storage_map'
failing:

  test_bpf_sk_storage_map:PASS:bpf_iter_bpf_sk_storage_map__open_and_load 0 nsec
  test_bpf_sk_storage_map:PASS:socket 0 nsec
  test_bpf_sk_storage_map:PASS:map_update 0 nsec
  test_bpf_sk_storage_map:PASS:socket 0 nsec
  test_bpf_sk_storage_map:PASS:map_update 0 nsec
  test_bpf_sk_storage_map:PASS:socket 0 nsec
  test_bpf_sk_storage_map:PASS:map_update 0 nsec
  test_bpf_sk_storage_map:PASS:attach_iter 0 nsec
  test_bpf_sk_storage_map:PASS:create_iter 0 nsec
  test_bpf_sk_storage_map:PASS:read 0 nsec
  test_bpf_sk_storage_map:FAIL:ipv6_sk_count got 0 expected 3
  $10/26 bpf_iter/bpf_sk_storage_map:FAIL

The code of the test case is simply, it will load sk->sk_family to the
register with BPF_PROBE_MEM and check if it is AF_INET6. With this patch,
now the test case 'bpf_iter' can pass:

  $10  bpf_iter:OK

Fixes: 2a02759ef5 ("bpf: Add support for BTF pointers to interpreter")
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20220524021228.533216-1-imagedong@tencent.com
2022-05-28 01:09:18 +02:00
Linus Torvalds
98931dd95f Yang Shi has improved the behaviour of khugepaged collapsing of readonly
file-backed transparent hugepages.
 
 Johannes Weiner has arranged for zswap memory use to be tracked and
 managed on a per-cgroup basis.
 
 Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for runtime
 enablement of the recent huge page vmemmap optimization feature.
 
 Baolin Wang contributes a series to fix some issues around hugetlb
 pagetable invalidation.
 
 Zhenwei Pi has fixed some interactions between hwpoisoned pages and
 virtualization.
 
 Tong Tiangen has enabled the use of the presently x86-only
 page_table_check debugging feature on arm64 and riscv.
 
 David Vernet has done some fixup work on the memcg selftests.
 
 Peter Xu has taught userfaultfd to handle write protection faults against
 shmem- and hugetlbfs-backed files.
 
 More DAMON development from SeongJae Park - adding online tuning of the
 feature and support for monitoring of fixed virtual address ranges.  Also
 easier discovery of which monitoring operations are available.
 
 Nadav Amit has done some optimization of TLB flushing during mprotect().
 
 Neil Brown continues to labor away at improving our swap-over-NFS support.
 
 David Hildenbrand has some fixes to anon page COWing versus
 get_user_pages().
 
 Peng Liu fixed some errors in the core hugetlb code.
 
 Joao Martins has reduced the amount of memory consumed by device-dax's
 compound devmaps.
 
 Some cleanups of the arch-specific pagemap code from Anshuman Khandual.
 
 Muchun Song has found and fixed some errors in the TLB flushing of
 transparent hugepages.
 
 Roman Gushchin has done more work on the memcg selftests.
 
 And, of course, many smaller fixes and cleanups.  Notably, the customary
 million cleanup serieses from Miaohe Lin.
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Merge tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "Almost all of MM here. A few things are still getting finished off,
  reviewed, etc.

   - Yang Shi has improved the behaviour of khugepaged collapsing of
     readonly file-backed transparent hugepages.

   - Johannes Weiner has arranged for zswap memory use to be tracked and
     managed on a per-cgroup basis.

   - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for
     runtime enablement of the recent huge page vmemmap optimization
     feature.

   - Baolin Wang contributes a series to fix some issues around hugetlb
     pagetable invalidation.

   - Zhenwei Pi has fixed some interactions between hwpoisoned pages and
     virtualization.

   - Tong Tiangen has enabled the use of the presently x86-only
     page_table_check debugging feature on arm64 and riscv.

   - David Vernet has done some fixup work on the memcg selftests.

   - Peter Xu has taught userfaultfd to handle write protection faults
     against shmem- and hugetlbfs-backed files.

   - More DAMON development from SeongJae Park - adding online tuning of
     the feature and support for monitoring of fixed virtual address
     ranges. Also easier discovery of which monitoring operations are
     available.

   - Nadav Amit has done some optimization of TLB flushing during
     mprotect().

   - Neil Brown continues to labor away at improving our swap-over-NFS
     support.

   - David Hildenbrand has some fixes to anon page COWing versus
     get_user_pages().

   - Peng Liu fixed some errors in the core hugetlb code.

   - Joao Martins has reduced the amount of memory consumed by
     device-dax's compound devmaps.

   - Some cleanups of the arch-specific pagemap code from Anshuman
     Khandual.

   - Muchun Song has found and fixed some errors in the TLB flushing of
     transparent hugepages.

   - Roman Gushchin has done more work on the memcg selftests.

  ... and, of course, many smaller fixes and cleanups. Notably, the
  customary million cleanup serieses from Miaohe Lin"

* tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits)
  mm: kfence: use PAGE_ALIGNED helper
  selftests: vm: add the "settings" file with timeout variable
  selftests: vm: add "test_hmm.sh" to TEST_FILES
  selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests
  selftests: vm: add migration to the .gitignore
  selftests/vm/pkeys: fix typo in comment
  ksm: fix typo in comment
  selftests: vm: add process_mrelease tests
  Revert "mm/vmscan: never demote for memcg reclaim"
  mm/kfence: print disabling or re-enabling message
  include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace"
  include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion"
  mm: fix a potential infinite loop in start_isolate_page_range()
  MAINTAINERS: add Muchun as co-maintainer for HugeTLB
  zram: fix Kconfig dependency warning
  mm/shmem: fix shmem folio swapoff hang
  cgroup: fix an error handling path in alloc_pagecache_max_30M()
  mm: damon: use HPAGE_PMD_SIZE
  tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate
  nodemask.h: fix compilation error with GCC12
  ...
2022-05-26 12:32:41 -07:00
Linus Torvalds
7e062cda7d Networking changes for 5.19.
Core
 ----
 
  - Support TCPv6 segmentation offload with super-segments larger than
    64k bytes using the IPv6 Jumbogram extension header (AKA BIG TCP).
 
  - Generalize skb freeing deferral to per-cpu lists, instead of
    per-socket lists.
 
  - Add a netdev statistic for packets dropped due to L2 address
    mismatch (rx_otherhost_dropped).
 
  - Continue work annotating skb drop reasons.
 
  - Accept alternative netdev names (ALT_IFNAME) in more netlink
    requests.
 
  - Add VLAN support for AF_PACKET SOCK_RAW GSO.
 
  - Allow receiving skb mark from the socket as a cmsg.
 
  - Enable memcg accounting for veth queues, sysctl tables and IPv6.
 
 BPF
 ---
 
  - Add libbpf support for User Statically-Defined Tracing (USDTs).
 
  - Speed up symbol resolution for kprobes multi-link attachments.
 
  - Support storing typed pointers to referenced and unreferenced
    objects in BPF maps.
 
  - Add support for BPF link iterator.
 
  - Introduce access to remote CPU map elements in BPF per-cpu map.
 
  - Allow middle-of-the-road settings for the
    kernel.unprivileged_bpf_disabled sysctl.
 
  - Implement basic types of dynamic pointers e.g. to allow for
    dynamically sized ringbuf reservations without extra memory copies.
 
 Protocols
 ---------
 
  - Retire port only listening_hash table, add a second bind table
    hashed by port and address. Avoid linear list walk when binding
    to very popular ports (e.g. 443).
 
  - Add bridge FDB bulk flush filtering support allowing user space
    to remove all FDB entries matching a condition.
 
  - Introduce accept_unsolicited_na sysctl for IPv6 to implement
    router-side changes for RFC9131.
 
  - Support for MPTCP path manager in user space.
 
  - Add MPTCP support for fallback to regular TCP for connections
    that have never connected additional subflows or transmitted
    out-of-sequence data (partial support for RFC8684 fallback).
 
  - Avoid races in MPTCP-level window tracking, stabilize and improve
    throughput.
 
  - Support lockless operation of GRE tunnels with seq numbers enabled.
 
  - WiFi support for host based BSS color collision detection.
 
  - Add support for SO_TXTIME/SCM_TXTIME on CAN sockets.
 
  - Support transmission w/o flow control in CAN ISOTP (ISO 15765-2).
 
  - Support zero-copy Tx with TLS 1.2 crypto offload (sendfile).
 
  - Allow matching on the number of VLAN tags via tc-flower.
 
  - Add tracepoint for tcp_set_ca_state().
 
 Driver API
 ----------
 
  - Improve error reporting from classifier and action offload.
 
  - Add support for listing line cards in switches (devlink).
 
  - Add helpers for reporting page pool statistics with ethtool -S.
 
  - Add support for reading clock cycles when using PTP virtual clocks,
    instead of having the driver convert to time before reporting.
    This makes it possible to report time from different vclocks.
 
  - Support configuring low-latency Tx descriptor push via ethtool.
 
  - Separate Clause 22 and Clause 45 MDIO accesses more explicitly.
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - Marvell's Octeon NIC PCI Endpoint support (octeon_ep)
    - Sunplus SP7021 SoC (sp7021_emac)
    - Add support for Renesas RZ/V2M (in ravb)
    - Add support for MediaTek mt7986 switches (in mtk_eth_soc)
 
  - Ethernet PHYs:
    - ADIN1100 industrial PHYs (w/ 10BASE-T1L and SQI reporting)
    - TI DP83TD510 PHY
    - Microchip LAN8742/LAN88xx PHYs
 
  - WiFi:
    - Driver for pureLiFi X, XL, XC devices (plfxlc)
    - Driver for Silicon Labs devices (wfx)
    - Support for WCN6750 (in ath11k)
    - Support Realtek 8852ce devices (in rtw89)
 
  - Mobile:
    - MediaTek T700 modems (Intel 5G 5000 M.2 cards)
 
  - CAN:
   - ctucanfd: add support for CTU CAN FD open-source IP core
     from Czech Technical University in Prague
 
 Drivers
 -------
 
  - Delete a number of old drivers still using virt_to_bus().
 
  - Ethernet NICs:
    - intel: support TSO on tunnels MPLS
    - broadcom: support multi-buffer XDP
    - nfp: support VF rate limiting
    - sfc: use hardware tx timestamps for more than PTP
    - mlx5: multi-port eswitch support
    - hyper-v: add support for XDP_REDIRECT
    - atlantic: XDP support (including multi-buffer)
    - macb: improve real-time perf by deferring Tx processing to NAPI
 
  - High-speed Ethernet switches:
    - mlxsw: implement basic line card information querying
    - prestera: add support for traffic policing on ingress and egress
 
  - Embedded Ethernet switches:
    - lan966x: add support for packet DMA (FDMA)
    - lan966x: add support for PTP programmable pins
    - ti: cpsw_new: enable bc/mc storm prevention
 
  - Qualcomm 802.11ax WiFi (ath11k):
    - Wake-on-WLAN support for QCA6390 and WCN6855
    - device recovery (firmware restart) support
    - support setting Specific Absorption Rate (SAR) for WCN6855
    - read country code from SMBIOS for WCN6855/QCA6390
    - enable keep-alive during WoWLAN suspend
    - implement remain-on-channel support
 
  - MediaTek WiFi (mt76):
    - support Wireless Ethernet Dispatch offloading packet movement
      between the Ethernet switch and WiFi interfaces
    - non-standard VHT MCS10-11 support
    - mt7921 AP mode support
    - mt7921 IPv6 NS offload support
 
  - Ethernet PHYs:
    - micrel: ksz9031/ksz9131: cabletest support
    - lan87xx: SQI support for T1 PHYs
    - lan937x: add interrupt support for link detection
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core
  ----

   - Support TCPv6 segmentation offload with super-segments larger than
     64k bytes using the IPv6 Jumbogram extension header (AKA BIG TCP).

   - Generalize skb freeing deferral to per-cpu lists, instead of
     per-socket lists.

   - Add a netdev statistic for packets dropped due to L2 address
     mismatch (rx_otherhost_dropped).

   - Continue work annotating skb drop reasons.

   - Accept alternative netdev names (ALT_IFNAME) in more netlink
     requests.

   - Add VLAN support for AF_PACKET SOCK_RAW GSO.

   - Allow receiving skb mark from the socket as a cmsg.

   - Enable memcg accounting for veth queues, sysctl tables and IPv6.

  BPF
  ---

   - Add libbpf support for User Statically-Defined Tracing (USDTs).

   - Speed up symbol resolution for kprobes multi-link attachments.

   - Support storing typed pointers to referenced and unreferenced
     objects in BPF maps.

   - Add support for BPF link iterator.

   - Introduce access to remote CPU map elements in BPF per-cpu map.

   - Allow middle-of-the-road settings for the
     kernel.unprivileged_bpf_disabled sysctl.

   - Implement basic types of dynamic pointers e.g. to allow for
     dynamically sized ringbuf reservations without extra memory copies.

  Protocols
  ---------

   - Retire port only listening_hash table, add a second bind table
     hashed by port and address. Avoid linear list walk when binding to
     very popular ports (e.g. 443).

   - Add bridge FDB bulk flush filtering support allowing user space to
     remove all FDB entries matching a condition.

   - Introduce accept_unsolicited_na sysctl for IPv6 to implement
     router-side changes for RFC9131.

   - Support for MPTCP path manager in user space.

   - Add MPTCP support for fallback to regular TCP for connections that
     have never connected additional subflows or transmitted
     out-of-sequence data (partial support for RFC8684 fallback).

   - Avoid races in MPTCP-level window tracking, stabilize and improve
     throughput.

   - Support lockless operation of GRE tunnels with seq numbers enabled.

   - WiFi support for host based BSS color collision detection.

   - Add support for SO_TXTIME/SCM_TXTIME on CAN sockets.

   - Support transmission w/o flow control in CAN ISOTP (ISO 15765-2).

   - Support zero-copy Tx with TLS 1.2 crypto offload (sendfile).

   - Allow matching on the number of VLAN tags via tc-flower.

   - Add tracepoint for tcp_set_ca_state().

  Driver API
  ----------

   - Improve error reporting from classifier and action offload.

   - Add support for listing line cards in switches (devlink).

   - Add helpers for reporting page pool statistics with ethtool -S.

   - Add support for reading clock cycles when using PTP virtual clocks,
     instead of having the driver convert to time before reporting. This
     makes it possible to report time from different vclocks.

   - Support configuring low-latency Tx descriptor push via ethtool.

   - Separate Clause 22 and Clause 45 MDIO accesses more explicitly.

  New hardware / drivers
  ----------------------

   - Ethernet:
      - Marvell's Octeon NIC PCI Endpoint support (octeon_ep)
      - Sunplus SP7021 SoC (sp7021_emac)
      - Add support for Renesas RZ/V2M (in ravb)
      - Add support for MediaTek mt7986 switches (in mtk_eth_soc)

   - Ethernet PHYs:
      - ADIN1100 industrial PHYs (w/ 10BASE-T1L and SQI reporting)
      - TI DP83TD510 PHY
      - Microchip LAN8742/LAN88xx PHYs

   - WiFi:
      - Driver for pureLiFi X, XL, XC devices (plfxlc)
      - Driver for Silicon Labs devices (wfx)
      - Support for WCN6750 (in ath11k)
      - Support Realtek 8852ce devices (in rtw89)

   - Mobile:
      - MediaTek T700 modems (Intel 5G 5000 M.2 cards)

   - CAN:
      - ctucanfd: add support for CTU CAN FD open-source IP core from
        Czech Technical University in Prague

  Drivers
  -------

   - Delete a number of old drivers still using virt_to_bus().

   - Ethernet NICs:
      - intel: support TSO on tunnels MPLS
      - broadcom: support multi-buffer XDP
      - nfp: support VF rate limiting
      - sfc: use hardware tx timestamps for more than PTP
      - mlx5: multi-port eswitch support
      - hyper-v: add support for XDP_REDIRECT
      - atlantic: XDP support (including multi-buffer)
      - macb: improve real-time perf by deferring Tx processing to NAPI

   - High-speed Ethernet switches:
      - mlxsw: implement basic line card information querying
      - prestera: add support for traffic policing on ingress and egress

   - Embedded Ethernet switches:
      - lan966x: add support for packet DMA (FDMA)
      - lan966x: add support for PTP programmable pins
      - ti: cpsw_new: enable bc/mc storm prevention

   - Qualcomm 802.11ax WiFi (ath11k):
      - Wake-on-WLAN support for QCA6390 and WCN6855
      - device recovery (firmware restart) support
      - support setting Specific Absorption Rate (SAR) for WCN6855
      - read country code from SMBIOS for WCN6855/QCA6390
      - enable keep-alive during WoWLAN suspend
      - implement remain-on-channel support

   - MediaTek WiFi (mt76):
      - support Wireless Ethernet Dispatch offloading packet movement
        between the Ethernet switch and WiFi interfaces
      - non-standard VHT MCS10-11 support
      - mt7921 AP mode support
      - mt7921 IPv6 NS offload support

   - Ethernet PHYs:
      - micrel: ksz9031/ksz9131: cabletest support
      - lan87xx: SQI support for T1 PHYs
      - lan937x: add interrupt support for link detection"

* tag 'net-next-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1809 commits)
  ptp: ocp: Add firmware header checks
  ptp: ocp: fix PPS source selector debugfs reporting
  ptp: ocp: add .init function for sma_op vector
  ptp: ocp: vectorize the sma accessor functions
  ptp: ocp: constify selectors
  ptp: ocp: parameterize input/output sma selectors
  ptp: ocp: revise firmware display
  ptp: ocp: add Celestica timecard PCI ids
  ptp: ocp: Remove #ifdefs around PCI IDs
  ptp: ocp: 32-bit fixups for pci start address
  Revert "net/smc: fix listen processing for SMC-Rv2"
  ath6kl: Use cc-disable-warning to disable -Wdangling-pointer
  selftests/bpf: Dynptr tests
  bpf: Add dynptr data slices
  bpf: Add bpf_dynptr_read and bpf_dynptr_write
  bpf: Dynptr support for ring buffers
  bpf: Add bpf_dynptr_from_mem for local dynptrs
  bpf: Add verifier support for dynptrs
  bpf: Suppress 'passing zero to PTR_ERR' warning
  bpf: Introduce bpf_arch_text_invalidate for bpf_prog_pack
  ...
2022-05-25 12:22:58 -07:00
Joanne Koong
34d4ef5775 bpf: Add dynptr data slices
This patch adds a new helper function

void *bpf_dynptr_data(struct bpf_dynptr *ptr, u32 offset, u32 len);

which returns a pointer to the underlying data of a dynptr. *len*
must be a statically known value. The bpf program may access the returned
data slice as a normal buffer (eg can do direct reads and writes), since
the verifier associates the length with the returned pointer, and
enforces that no out of bounds accesses occur.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-6-joannelkoong@gmail.com
2022-05-23 14:31:28 -07:00
Joanne Koong
13bbbfbea7 bpf: Add bpf_dynptr_read and bpf_dynptr_write
This patch adds two helper functions, bpf_dynptr_read and
bpf_dynptr_write:

long bpf_dynptr_read(void *dst, u32 len, struct bpf_dynptr *src, u32 offset);

long bpf_dynptr_write(struct bpf_dynptr *dst, u32 offset, void *src, u32 len);

The dynptr passed into these functions must be valid dynptrs that have
been initialized.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-5-joannelkoong@gmail.com
2022-05-23 14:31:28 -07:00
Joanne Koong
bc34dee65a bpf: Dynptr support for ring buffers
Currently, our only way of writing dynamically-sized data into a ring
buffer is through bpf_ringbuf_output but this incurs an extra memcpy
cost. bpf_ringbuf_reserve + bpf_ringbuf_commit avoids this extra
memcpy, but it can only safely support reservation sizes that are
statically known since the verifier cannot guarantee that the bpf
program won’t access memory outside the reserved space.

The bpf_dynptr abstraction allows for dynamically-sized ring buffer
reservations without the extra memcpy.

There are 3 new APIs:

long bpf_ringbuf_reserve_dynptr(void *ringbuf, u32 size, u64 flags, struct bpf_dynptr *ptr);
void bpf_ringbuf_submit_dynptr(struct bpf_dynptr *ptr, u64 flags);
void bpf_ringbuf_discard_dynptr(struct bpf_dynptr *ptr, u64 flags);

These closely follow the functionalities of the original ringbuf APIs.
For example, all ringbuffer dynptrs that have been reserved must be
either submitted or discarded before the program exits.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-4-joannelkoong@gmail.com
2022-05-23 14:31:28 -07:00
Joanne Koong
263ae152e9 bpf: Add bpf_dynptr_from_mem for local dynptrs
This patch adds a new api bpf_dynptr_from_mem:

long bpf_dynptr_from_mem(void *data, u32 size, u64 flags, struct bpf_dynptr *ptr);

which initializes a dynptr to point to a bpf program's local memory. For now
only local memory that is of reg type PTR_TO_MAP_VALUE is supported.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-3-joannelkoong@gmail.com
2022-05-23 14:31:24 -07:00