33479 Commits

Author SHA1 Message Date
Andrii Nakryiko
3a95c42d65 libbpf: Define arm syscall regs spec in bpf_tracing.h
Define explicit table of registers used for syscall argument passing.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-17-andrii@kernel.org
2023-01-23 20:53:01 +01:00
Andrii Nakryiko
e82b96a3a9 libbpf: Define s390x syscall regs spec in bpf_tracing.h
Define explicit table of registers used for syscall argument passing.
Note that we need custom overrides for PT_REGS_PARM1_[CORE_]SYSCALL
macros due to the need to use BPF CO-RE and custom local pt_regs
definitions to fetch orig_gpr2, storing 1st argument.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # s390x
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-16-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
ff00f9cbd2 libbpf: Define i386 syscall regs spec in bpf_tracing.h
Define explicit table of registers used for syscall argument passing.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-15-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
d21fbceedd libbpf: Define x86-64 syscall regs spec in bpf_tracing.h
Define explicit table of registers used for syscall argument passing.
Remove now unnecessary overrides of PT_REGS_PARM5_[CORE_]SYSCALL macros.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-14-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
8ccabeef91 libbpf: Improve syscall tracing support in bpf_tracing.h
Set up generic support in bpf_tracing.h for up to 7 syscall arguments
tracing with BPF_KSYSCALL, which seems to be the limit according to
syscall(2) manpage. Also change the way that syscall convention is
specified to be more explicit. Subsequent patches will adjust and define
proper per-architecture syscall conventions.

__PT_PARM1_SYSCALL_REG through __PT_PARM6_SYSCALL_REG is added
temporarily to keep everything working before each architecture has
syscall reg tables defined. They will be removed afterwards.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com> # arm64
Link: https://lore.kernel.org/bpf/20230120200914.3008030-13-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
bc72742beb selftests/bpf: Validate arch-specific argument registers limits
Update uprobe_autoattach selftest to validate architecture-specific
argument passing through registers. Use new BPF_UPROBE and
BPF_URETPROBE, and construct both BPF-side and user-space side in such
a way that for different architectures we are fetching and checking
different number of arguments, matching architecture-specific limit of
how many registers are available for argument passing.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com> # arm64
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # s390x
Link: https://lore.kernel.org/bpf/20230120200914.3008030-12-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
ac4afd6e6f libbpf: Add BPF_UPROBE and BPF_URETPROBE macro aliases
Add BPF_UPROBE and BPF_URETPROBE macros, aliased to BPF_KPROBE and
BPF_KRETPROBE, respectively. This makes uprobe-based BPF program code
much less confusing, especially to people new to tracing, at no cost in
terms of maintainability. We'll use this macro in selftests in
subsequent patch.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-11-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
55ff00d539 libbpf: Complete LoongArch (loongarch) spec in bpf_tracing.h
Add PARM6 through PARM8 definitions. Add kernel docs link describing ABI
for LoongArch.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-10-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
0ac0865679 libbpf: Fix and complete ARC spec in bpf_tracing.h
Add PARM6 through PARM8 definitions. Also fix frame pointer (FP)
register definition. Also leave a link to where to find ABI spec.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-9-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
b13ed8ca7f libbpf: Complete riscv arch spec in bpf_tracing.h
Add PARM6 through PARM8 definitions for RISC V (riscv) arch. Leave the
link for ABI doc for future reference.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Pu Lehui <pulehui@huawei.com> # RISC-V
Link: https://lore.kernel.org/bpf/20230120200914.3008030-8-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
7f60f5d85e libbpf: Complete sparc spec in bpf_tracing.h
Add PARM6 definition for sparc architecture. Leave a link to calling
convention documentation.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-7-andrii@kernel.org
2023-01-23 20:53:00 +01:00
Andrii Nakryiko
2eb2be30b8 libbpf: Complete powerpc spec in bpf_tracing.h
Add definitions of PARM6 through PARM8 for powerpc architecture. Add
also a link to a functiona call sequence documentation for future reference.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-6-andrii@kernel.org
2023-01-23 20:52:59 +01:00
Andrii Nakryiko
1222445a5b libbpf: Complete mips spec in bpf_tracing.h
Add registers for PARM6 through PARM8. Add a link to an ABI. We don't
distinguish between O32, N32, and N64, so document that we assume N64
right now.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-5-andrii@kernel.org
2023-01-23 20:52:59 +01:00
Andrii Nakryiko
1dac40ac87 libbpf: Fix arm and arm64 specs in bpf_tracing.h
Remove invalid support for PARM5 on 32-bit arm, as per ABI. Add three
more argument registers for arm64. Also leave links to ABI specs for
future reference.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com> # arm64
Link: https://lore.kernel.org/bpf/20230120200914.3008030-4-andrii@kernel.org
2023-01-23 20:52:59 +01:00
Andrii Nakryiko
013290329a libbpf: Add 6th argument support for x86-64 in bpf_tracing.h
Add r9 as register containing 6th argument on x86-64 architecture, as
per its ABI. Add also a link to a page describing ABI for easier future
reference.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-3-andrii@kernel.org
2023-01-23 20:52:59 +01:00
Andrii Nakryiko
3c59623d82 libbpf: Add support for fetching up to 8 arguments in kprobes
Add BPF_KPROBE() and PT_REGS_PARMx() support for up to 8 arguments, if
target architecture supports this. Currently all architectures are
limited to only 5 register-placed arguments, which is limiting even on
x86-64.

This patch adds generic macro machinery to support up to 8 arguments
both when explicitly fetching it from pt_regs through PT_REGS_PARMx()
macros, as well as more ergonomic access in BPF_KPROBE().

Also, for i386 architecture we now don't have to define fake PARM4 and
PARM5 definitions, they will be generically substituted, just like for
PARM6 through PARM8.

Subsequent patches will fill out architecture-specific definitions,
where appropriate.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com> # arm64
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # s390x
Link: https://lore.kernel.org/bpf/20230120200914.3008030-2-andrii@kernel.org
2023-01-23 20:52:59 +01:00
David Vernet
7525daeefc selftests/bpf: Use __failure macro in task kfunc testsuite
In commit 537c3f66eac1 ("selftests/bpf: add generic BPF program tester-loader"),
a new mechanism was added to the BPF selftest framework to allow testsuites to
use macros to define expected failing testcases.

This allows any testsuite which tests verification failure to remove a good
amount of boilerplate code. This patch updates the task_kfunc selftest suite
to use these new macros.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230120021844.3048244-1-void@manifault.com
2023-01-23 20:32:20 +01:00
Stanislav Fomichev
297a3f1241 selftests/bpf: Simple program to dump XDP RX metadata
To be used for verification of driver implementations. Note that
the skb path is gone from the series, but I'm still keeping the
implementation for any possible future work.

$ xdp_hw_metadata <ifname>

On the other machine:

$ echo -n xdp | nc -u -q1 <target> 9091 # for AF_XDP
$ echo -n skb | nc -u -q1 <target> 9092 # for skb

Sample output:

  # xdp
  xsk_ring_cons__peek: 1
  0x19f9090: rx_desc[0]->addr=100000000008000 addr=8100 comp_addr=8000
  rx_timestamp_supported: 1
  rx_timestamp: 1667850075063948829
  0x19f9090: complete idx=8 addr=8000

  # skb
  found skb hwtstamp = 1668314052.854274681

Decoding:
  # xdp
  rx_timestamp=1667850075.063948829

  $ date -d @1667850075
  Mon Nov  7 11:41:15 AM PST 2022
  $ date
  Mon Nov  7 11:42:05 AM PST 2022

  # skb
  $ date -d @1668314052
  Sat Nov 12 08:34:12 PM PST 2022
  $ date
  Sat Nov 12 08:37:06 PM PST 2022

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-18-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-23 10:00:24 -08:00
Stanislav Fomichev
e2a46d54d7 selftests/bpf: Verify xdp_metadata xdp->af_xdp path
- create new netns
- create veth pair (veTX+veRX)
- setup AF_XDP socket for both interfaces
- attach bpf to veRX
- send packet via veTX
- verify the packet has expected metadata at veRX

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-12-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-23 09:58:21 -08:00
Stanislav Fomichev
4053570462 selftests/bpf: Update expected test_offload.py messages
Generic check has a different error message, update the selftest.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-7-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-23 09:38:10 -08:00
Stanislav Fomichev
2b3486bc2d bpf: Introduce device-bound XDP programs
New flag BPF_F_XDP_DEV_BOUND_ONLY plus all the infra to have a way
to associate a netdev with a BPF program at load time.

netdevsim checks are dropped in favor of generic check in dev_xdp_attach.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-6-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-23 09:38:10 -08:00
Kumar Kartikeya Dwivedi
ae8e354c49 selftests/bpf: Add dynptr helper tests
First test that we allow overwriting dynptr slots and reinitializing
them in unreferenced case, and disallow overwriting for referenced case.
Include tests to ensure slices obtained from destroyed dynptrs are being
invalidated on their destruction. The destruction needs to be scoped, as
in slices of dynptr A should not be invalidated when dynptr B is
destroyed. Next, test that MEM_UNINIT doesn't allow writing dynptr stack
slots.

Acked-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-13-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-20 17:55:04 -08:00
Kumar Kartikeya Dwivedi
011edc8e49 selftests/bpf: Add dynptr partial slot overwrite tests
Try creating a dynptr, then overwriting second slot with first slot of
another dynptr. Then, the first slot of first dynptr should also be
invalidated, but without our fix that does not happen. As a consequence,
the unfixed case allows passing first dynptr (as the kernel check only
checks for slot_type and then first_slot == true).

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-12-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-20 17:55:03 -08:00
Kumar Kartikeya Dwivedi
ef48101353 selftests/bpf: Add dynptr var_off tests
Ensure that variable offset is handled correctly, and verifier takes
both fixed and variable part into account. Also ensures that only
constant var_off is allowed.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-11-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-20 17:55:03 -08:00
Kumar Kartikeya Dwivedi
f4d24edf1b selftests/bpf: Add dynptr pruning tests
Add verifier tests that verify the new pruning behavior for STACK_DYNPTR
slots, and ensure that state equivalence takes into account changes to
the old and current verifier state correctly. Also ensure that the
stacksafe changes are actually enabling pruning in case states are
equivalent from pruning PoV.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-10-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-20 17:55:03 -08:00
Eduard Zingerman
91b875a5e4 selftests/bpf: convenience macro for use with 'asm volatile' blocks
A set of macros useful for writing naked BPF functions using inline
assembly. E.g. as follows:

struct map_struct {
	...
} map SEC(".maps");

SEC(...)
__naked int foo_test(void)
{
	asm volatile(
		"r0 = 0;"
		"*(u64*)(r10 - 8) = r0;"
		"r1 = %[map] ll;"
		"r2 = r10;"
		"r2 += -8;"
		"call %[bpf_map_lookup_elem];"
		"r0 = 0;"
		"exit;"
		:
		: __imm(bpf_map_lookup_elem),
		  __imm_addr(map)
		: __clobber_all);
}

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
[ Kartikeya: Add acks, include __clobber_common from Andrii ]
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-9-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-20 17:55:03 -08:00
Kumar Kartikeya Dwivedi
f8064ab90d bpf: Invalidate slices on destruction of dynptrs on stack
The previous commit implemented destroy_if_dynptr_stack_slot. It
destroys the dynptr which given spi belongs to, but still doesn't
invalidate the slices that belong to such a dynptr. While for the case
of referenced dynptr, we don't allow their overwrite and return an error
early, we still allow it and destroy the dynptr for unreferenced dynptr.

To be able to enable precise and scoped invalidation of dynptr slices in
this case, we must be able to associate the source dynptr of slices that
have been obtained using bpf_dynptr_data. When doing destruction, only
slices belonging to the dynptr being destructed should be invalidated,
and nothing else. Currently, dynptr slices belonging to different
dynptrs are indistinguishible.

Hence, allocate a unique id to each dynptr (CONST_PTR_TO_DYNPTR and
those on stack). This will be stored as part of reg->id. Whenever using
bpf_dynptr_data, transfer this unique dynptr id to the returned
PTR_TO_MEM_OR_NULL slice pointer, and store it in a new per-PTR_TO_MEM
dynptr_id register state member.

Finally, after establishing such a relationship between dynptrs and
their slices, implement precise invalidation logic that only invalidates
slices belong to the destroyed dynptr in destroy_if_dynptr_stack_slot.

Acked-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-5-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-20 17:55:03 -08:00
Kumar Kartikeya Dwivedi
ef8fc7a07c bpf: Fix partial dynptr stack slot reads/writes
Currently, while reads are disallowed for dynptr stack slots, writes are
not. Reads don't work from both direct access and helpers, while writes
do work in both cases, but have the effect of overwriting the slot_type.

While this is fine, handling for a few edge cases is missing. Firstly,
a user can overwrite the stack slots of dynptr partially.

Consider the following layout:
spi: [d][d][?]
      2  1  0

First slot is at spi 2, second at spi 1.
Now, do a write of 1 to 8 bytes for spi 1.

This will essentially either write STACK_MISC for all slot_types or
STACK_MISC and STACK_ZERO (in case of size < BPF_REG_SIZE partial write
of zeroes). The end result is that slot is scrubbed.

Now, the layout is:
spi: [d][m][?]
      2  1  0

Suppose if user initializes spi = 1 as dynptr.
We get:
spi: [d][d][d]
      2  1  0

But this time, both spi 2 and spi 1 have first_slot = true.

Now, when passing spi 2 to dynptr helper, it will consider it as
initialized as it does not check whether second slot has first_slot ==
false. And spi 1 should already work as normal.

This effectively replaced size + offset of first dynptr, hence allowing
invalid OOB reads and writes.

Make a few changes to protect against this:
When writing to PTR_TO_STACK using BPF insns, when we touch spi of a
STACK_DYNPTR type, mark both first and second slot (regardless of which
slot we touch) as STACK_INVALID. Reads are already prevented.

Second, prevent writing	to stack memory from helpers if the range may
contain any STACK_DYNPTR slots. Reads are already prevented.

For helpers, we cannot allow it to destroy dynptrs from the writes as
depending on arguments, helper may take uninit_mem and dynptr both at
the same time. This would mean that helper may write to uninit_mem
before it reads the dynptr, which would be bad.

PTR_TO_MEM: [?????dd]

Depending on the code inside the helper, it may end up overwriting the
dynptr contents first and then read those as the dynptr argument.

Verifier would only simulate destruction when it does byte by byte
access simulation in check_helper_call for meta.access_size, and
fail to catch this case, as it happens after argument checks.

The same would need to be done for any other non-trivial objects created
on the stack in the future, such as bpf_list_head on stack, or
bpf_rb_root on stack.

A common misunderstanding in the current code is that MEM_UNINIT means
writes, but note that writes may also be performed even without
MEM_UNINIT in case of helpers, in that case the code after handling meta
&& meta->raw_mode will complain when it sees STACK_DYNPTR. So that
invalid read case also covers writes to potential STACK_DYNPTR slots.
The only loophole was in case of meta->raw_mode which simulated writes
through instructions which could overwrite them.

A future series sequenced after this will focus on the clean up of
helper access checks and bugs around that.

Fixes: 97e03f521050 ("bpf: Add verifier support for dynptrs")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-20 17:55:03 -08:00
Kumar Kartikeya Dwivedi
79168a669d bpf: Fix missing var_off check for ARG_PTR_TO_DYNPTR
Currently, the dynptr function is not checking the variable offset part
of PTR_TO_STACK that it needs to check. The fixed offset is considered
when computing the stack pointer index, but if the variable offset was
not a constant (such that it could not be accumulated in reg->off), we
will end up a discrepency where runtime pointer does not point to the
actual stack slot we mark as STACK_DYNPTR.

It is impossible to precisely track dynptr state when variable offset is
not constant, hence, just like bpf_timer, kptr, bpf_spin_lock, etc.
simply reject the case where reg->var_off is not constant. Then,
consider both reg->off and reg->var_off.value when computing the stack
pointer index.

A new helper dynptr_get_spi is introduced to hide over these details
since the dynptr needs to be located in multiple places outside the
process_dynptr_func checks, hence once we know it's a PTR_TO_STACK, we
need to enforce these checks in all places.

Note that it is disallowed for unprivileged users to have a non-constant
var_off, so this problem should only be possible to trigger from
programs having CAP_PERFMON. However, its effects can vary.

Without the fix, it is possible to replace the contents of the dynptr
arbitrarily by making verifier mark different stack slots than actual
location and then doing writes to the actual stack address of dynptr at
runtime.

Fixes: 97e03f521050 ("bpf: Add verifier support for dynptrs")
Acked-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-20 17:55:02 -08:00
Jiri Olsa
edac4b5b18 selftests/bpf: Add serial_test_kprobe_multi_bench_attach_kernel/module tests
Add bench test for module portion of the symbols as well.

  # ./test_progs -v -t kprobe_multi_bench_attach_module
  bpf_testmod.ko is already unloaded.
  Loading bpf_testmod.ko...
  Successfully loaded bpf_testmod.ko.
  test_kprobe_multi_bench_attach:PASS:get_syms 0 nsec
  test_kprobe_multi_bench_attach:PASS:kprobe_multi_empty__open_and_load 0 nsec
  test_kprobe_multi_bench_attach:PASS:bpf_program__attach_kprobe_multi_opts 0 nsec
  test_kprobe_multi_bench_attach: found 26620 functions
  test_kprobe_multi_bench_attach: attached in   0.182s
  test_kprobe_multi_bench_attach: detached in   0.082s
  #96      kprobe_multi_bench_attach_module:OK
  Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
  Successfully unloaded bpf_testmod.ko.

It's useful for testing kprobe multi link modules resolving.

Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230116101009.23694-3-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-19 17:07:15 -08:00
Tiezhu Yang
92afc5329a selftests/bpf: Fix build errors if CONFIG_NF_CONNTRACK=m
If CONFIG_NF_CONNTRACK=m, there are no definitions of NF_NAT_MANIP_SRC
and NF_NAT_MANIP_DST in vmlinux.h, build test_bpf_nf.c failed.

$ make -C tools/testing/selftests/bpf/

  CLNG-BPF [test_maps] test_bpf_nf.bpf.o
progs/test_bpf_nf.c:160:42: error: use of undeclared identifier 'NF_NAT_MANIP_SRC'
                bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
                                                       ^
progs/test_bpf_nf.c:163:42: error: use of undeclared identifier 'NF_NAT_MANIP_DST'
                bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
                                                       ^
2 errors generated.

Copy the definitions in include/net/netfilter/nf_nat.h to test_bpf_nf.c,
in order to avoid redefinitions if CONFIG_NF_CONNTRACK=y, rename them with
___local suffix. This is similar with commit 1058b6a78db2 ("selftests/bpf:
Do not fail build if CONFIG_NF_CONNTRACK=m/n").

Fixes: b06b45e82b59 ("selftests/bpf: add tests for bpf_ct_set_nat_info kfunc")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/1674028604-7113-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-18 13:33:45 -08:00
Jiri Olsa
c0f264e4ed bpf/selftests: Add verifier tests for loading sleepable programs
Adding verifier tests for loading all types od allowed
sleepable programs plus reject for tp_btf type.

Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230117223705.440975-2-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-17 16:56:04 -08:00
Ziyang Xuan
7105f76fb5 selftests/bpf: add ipip6 and ip6ip decap to test_tc_tunnel
Add ipip6 and ip6ip decap testcases. Verify that bpf_skb_adjust_room()
correctly decapsulate ipip6 and ip6ip tunnel packets.

Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/dfd2d8cfdf9111bd129170d4345296f53bee6a67.1673574419.git.william.xuanziyang@huawei.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-15 12:56:17 -08:00
Ziyang Xuan
d219df60a7 bpf: Add ipip6 and ip6ip decap support for bpf_skb_adjust_room()
Add ipip6 and ip6ip decap support for bpf_skb_adjust_room().
Main use case is for using cls_bpf on ingress hook to decapsulate
IPv4 over IPv6 and IPv6 over IPv4 tunnel packets.

Add two new flags BPF_F_ADJ_ROOM_DECAP_L3_IPV{4,6} to indicate the
new IP header version after decapsulating the outer IP header.

Suggested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/b268ec7f0ff9431f4f43b1b40ab856ebb28cb4e1.1673574419.git.william.xuanziyang@huawei.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-15 12:56:17 -08:00
Roberto Valenzuela
1c48391bc6 selftests/bpf: Fix missing space error
Add the missing space after 'dest' variable assignment.
This change will resolve the following checkpatch.pl
script error:

ERROR: spaces required around that '+=' (ctx:VxW)

Signed-off-by: Roberto Valenzuela <valenzuelarober@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230113180257.39769-1-valenzuelarober@gmail.com
2023-01-13 14:23:02 -08:00
Menglong Dong
2fa0745365 libbpf: Replace '.' with '_' in legacy kprobe event name
'.' is not allowed in the event name of kprobe. Therefore, we will get a
EINVAL if the kernel function name has a '.' in legacy kprobe attach
case, such as 'icmp_reply.constprop.0'.

In order to adapt this case, we need to replace the '.' with other char
in gen_kprobe_legacy_event_name(). And I use '_' for this propose.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20230113093427.1666466-1-imagedong@tencent.com
2023-01-13 14:05:47 -08:00
Holger Hoffstätte
878625e1c7 bpftool: Always disable stack protection for BPF objects
When the clang toolchain has stack protection enabled in order to be
consistent with gcc - which just happens to be the case on Gentoo -
the bpftool build fails:

  [...]
  clang \
	-I. \
	-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/include/uapi/ \
	-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/bpf/bpftool/bootstrap/libbpf/include \
	-g -O2 -Wall -target bpf -c skeleton/pid_iter.bpf.c -o pid_iter.bpf.o
  clang \
	-I. \
	-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/include/uapi/ \
	-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/bpf/bpftool/bootstrap/libbpf/include \
	-g -O2 -Wall -target bpf -c skeleton/profiler.bpf.c -o profiler.bpf.o
  skeleton/profiler.bpf.c:40:14: error: A call to built-in function '__stack_chk_fail' is not supported.
  int BPF_PROG(fentry_XXX)
                ^
  skeleton/profiler.bpf.c:94:14: error: A call to built-in function '__stack_chk_fail' is not supported.
  int BPF_PROG(fexit_XXX)
                ^
  2 errors generated.
  [...]

Since stack-protector makes no sense for the BPF bits just unconditionally
disable it.

Bug: https://bugs.gentoo.org/890638
Signed-off-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/74cd9d2e-6052-312a-241e-2b514a75c92c@applied-asynchrony.com
2023-01-13 16:44:21 +01:00
Magnus Karlsson
7d8319a7cc selftests/xsk: automatically switch XDP programs
Implement automatic switching of XDP programs and execution modes if
needed by a test. This makes it much simpler to write a test as it
only has to say what XDP program it needs if it is not the default
one. This also makes it possible to remove the initial explicit
attachment of the XDP program as well as the explicit mode switch in
the code. These are now handled by the same code that just checks if a
switch is necessary, so no special cases are needed.

The default XDP program for all tests is one that sends all packets to
the AF_XDP socket. If you need another one, please use the new
function test_spec_set_xdp_prog() to specify what XDP programs and
maps to use for this test.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-16-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
e67b2554f3 selftests/xsk: automatically restore packet stream
Automatically restore the default packet stream if needed at the end
of each test. This so that test writers do not forget to do this.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-15-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
7f88198407 selftests/xsk: merge dual and single thread dispatchers
Make the thread dispatching code common by unifying the dual and
single thread dispatcher code. This so we do not have to add code in
two places in upcoming commits.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-14-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
80bea9acab selftests/xsk: add test when some packets are XDP_DROPed
Add a new test where some of the packets are not passed to the AF_XDP
socket and instead get a XDP_DROP verdict. This is important as it
tests the recycling mechanism of the buffer pool. If a packet is not
sent to the AF_XDP socket, the buffer the packet resides in is instead
recycled so it can be used again without the round-trip to user
space. The test introduces a new XDP program that drops every other
packet.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-13-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
f0a249df1b selftests/xsk: get rid of built-in XDP program
Get rid of the built-in XDP program that was part of the old libbpf
code in xsk.c and replace it with an eBPF program build using the
framework by all the other bpf selftests. This will form the base for
adding more programs in later commits.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-12-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
6b3c0821ca selftests/xsk: remove unnecessary code in control path
Remove unnecessary code in the control path. This is located in the
file xsk.c that was moved from libbpf when the xsk support there was
deprecated. Some of the code there is not needed anymore as the
selftests are only guaranteed to run on the kernel it is shipped
with. Therefore, all the code that has to deal with compatibility of
older kernels can be dropped and also any other function that is not
of any use for the tests.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-11-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
aa61d81f39 selftests/xsk: load and attach XDP program only once per mode
Load and attach the XDP program only once per XDP mode that is being
executed. Today, the XDP program is loaded and attached for every
test, then unloaded, which takes a long time on real NICs, since they
have to reconfigure their HW, in contrast to veth. The test suite now
completes in 21 seconds, instead of 207 seconds previously on my
machine. This is a speed-up of around 10x.

This is accomplished by moving the XDP loading from the worker threads
to the main thread and replacing the XDP loading interfaces of xsk.c
that was taken from the xsk support in libbpf, with something more
explicit that is more useful for these tests. Instead, the relevant
file descriptors and ifindexes are just passed down to the new
functions.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-10-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
64aef77d75 selftests/xsk: remove namespaces
Remove the namespaces used as they fill no function. This will
simplify the code for speeding up the tests in the following commits.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-9-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
efe620e5ba selftests/xsk: replace asm acquire/release implementations
Replace our own homegrown assembly store/release and load/acquire
implementations with the HW agnositic atomic APIs C11 offers. This to
make the code more portable, easier to read, and reduce the
maintenance burden.

The original code used load-acquire and store-release barriers
hand-coded in assembly. Since C11, these kind of operations are
offered as built-ins in gcc and llvm. The load-acquire operation
prevents hoisting of non-atomic memory operations to before this
operation and it corresponds to the __ATOMIC_ACQUIRE operation in the
built-in atomics. The store-release operation prevents hoisting of
non-atomic memory operations to after this operation and it
corresponds to the __ATOMIC_RELEASE operation in the built-in atomics.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-8-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:52 -08:00
Magnus Karlsson
703bfd3710 selftests/xsk: add debug option for creating netdevs
Add a new option to the test_xsk.sh script that only creates the two
veth netdevs and the extra namespace, then exits without running any
tests. The failed test can then be executed in the debugger without
having to create the netdevs and namespace manually. For ease-of-use,
the veth netdevs to use are printed so they can be copied into the
debugger.

Here is an example how to use it:

> sudo ./test_xsk.sh -d

veth10 veth11

> gdb xskxceiver

In gdb:

run -i veth10 -i veth11

And now the test cases can be debugged with gdb.

If you want to debug the test suite on a real NIC in loopback mode,
there is no need to use this feature as you already know the netdev of
your NIC.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-7-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:51 -08:00
Magnus Karlsson
a4ca62277b selftests/xsk: remove unused variable outstanding_tx
Remove the unused variable outstanding_tx.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-6-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:51 -08:00
Magnus Karlsson
085dcccfb7 selftests/xsk: print correct error codes when exiting
Print the correct error codes when exiting the test suite due to some
terminal error. Some of these had a switched sign and some of them
printed zero instead of errno.

Fixes: facb7cb2e909 ("selftests/bpf: Xsk selftests - SKB POLL, NOPOLL")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-5-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:51 -08:00
Magnus Karlsson
1e04f23bcc selftests/xsk: submit correct number of frames in populate_fill_ring
Submit the correct number of frames in the function
xsk_populate_fill_ring(). For the tests that set the flag
use_addr_for_fill, uninitialized buffers were sent to the fill ring
following the correct ones. This has no impact on the tests, since
they only use the ones that were initialized. But for correctness,
this should be fixed.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230111093526.11682-4-magnus.karlsson@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-11 18:16:51 -08:00