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
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
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
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
In commit 537c3f66ea ("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
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>
Instead of rejecting the attaching of PROG_TYPE_EXT programs to XDP
programs that consume HW metadata, implement support for propagating the
offload information. The extension program doesn't need to set a flag or
ifindex, these will just be propagated from the target by the verifier.
We need to create a separate offload object for the extension program,
though, since it can be reattached to a different program later (which
means we can't just inherit the offload information from the target).
An additional check is added on attach that the new target is compatible
with the offload information in the extension prog.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-9-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Kumar Kartikeya Dwivedi says:
====================
This is part 2 of https://lore.kernel.org/bpf/20221018135920.726360-1-memxor@gmail.com.
Changelog:
----------
v4 -> v5
v5: https://lore.kernel.org/bpf/20230120070355.1983560-1-memxor@gmail.com
* Add comments, tests from Joanne
* Add Joanne's acks
v3 -> v4
v3: https://lore.kernel.org/bpf/20230120034314.1921848-1-memxor@gmail.com
* Adopt BPF ASM tests to more readable style (Alexei)
v2 -> v3
v2: https://lore.kernel.org/bpf/20230119021442.1465269-1-memxor@gmail.com
* Fix slice invalidation logic for unreferenced dynptrs (Joanne)
* Add selftests for precise slice invalidation on destruction
* Add Joanne's acks
v1 -> v2
v1: https://lore.kernel.org/bpf/20230101083403.332783-1-memxor@gmail.com
* Return error early in case of overwriting referenced dynptr slots (Andrii, Joanne)
* Rename destroy_stack_slots_dynptr to destroy_if_dynptr_stack_slot (Joanne)
* Invalidate dynptr slices associated with dynptr in destroy_if_dynptr_stack_slot (Joanne)
* Combine both dynptr_get_spi and is_spi_bounds_valid (Joanne)
* Compute spi once in process_dynptr_func and pass it as parameter instead of recomputing (Joanne)
* Add comments expanding REG_LIVE_WRITTEN marking in unmark_stack_slots_dynptr (Joanne)
* Add comments explaining why destroy_if_dynptr_stack_slot call needs to be done for both spi
and spi - 1 (Joanne)
* Port BPF assembly tests from test_verifier to test_progs framework (Andrii)
* Address misc feedback, rebase to bpf-next
Old v1 -> v1
Old v1: https://lore.kernel.org/bpf/20221018135920.726360-1-memxor@gmail.com
* Allow overwriting dynptr stack slots from dynptr init helpers
* Fix a bug in alignment check where reg->var_off.value was still not included
* Address other minor nits
Eduard Zingerman (1):
selftests/bpf: convenience macro for use with 'asm volatile' blocks
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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>
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>
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>
Currently, process_dynptr_func first calls dynptr_get_spi and then
is_dynptr_reg_valid_init and is_dynptr_reg_valid_uninit have to call it
again to obtain the spi value. Instead of doing this twice, reuse the
already obtained value (which is by default 0, and is only set for
PTR_TO_STACK, and only used in that case in aforementioned functions).
The input value for these two functions will either be -ERANGE or >= 1,
and can either be permitted or rejected based on the respective check.
Suggested-by: Joanne Koong <joannelkoong@gmail.com>
Acked-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230121002241.2113993-8-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
