1551 Commits

Author SHA1 Message Date
Linus Torvalds 3d5ad2d4ec Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Daniel Borkmann:

 - Fix BPF verifier to not affect subreg_def marks in its range
   propagation (Eduard Zingerman)

 - Fix a truncation bug in the BPF verifier's handling of
   coerce_reg_to_size_sx (Dimitar Kanaliev)

 - Fix the BPF verifier's delta propagation between linked registers
   under 32-bit addition (Daniel Borkmann)

 - Fix a NULL pointer dereference in BPF devmap due to missing rxq
   information (Florian Kauer)

 - Fix a memory leak in bpf_core_apply (Jiri Olsa)

 - Fix an UBSAN-reported array-index-out-of-bounds in BTF parsing for
   arrays of nested structs (Hou Tao)

 - Fix build ID fetching where memory areas backing the file were
   created with memfd_secret (Andrii Nakryiko)

 - Fix BPF task iterator tid filtering which was incorrectly using pid
   instead of tid (Jordan Rome)

 - Several fixes for BPF sockmap and BPF sockhash redirection in
   combination with vsocks (Michal Luczaj)

 - Fix riscv BPF JIT and make BPF_CMPXCHG fully ordered (Andrea Parri)

 - Fix riscv BPF JIT under CONFIG_CFI_CLANG to prevent the possibility
   of an infinite BPF tailcall (Pu Lehui)

 - Fix a build warning from resolve_btfids that bpf_lsm_key_free cannot
   be resolved (Thomas Weißschuh)

 - Fix a bug in kfunc BTF caching for modules where the wrong BTF object
   was returned (Toke Høiland-Jørgensen)

 - Fix a BPF selftest compilation error in cgroup-related tests with
   musl libc (Tony Ambardar)

 - Several fixes to BPF link info dumps to fill missing fields (Tyrone
   Wu)

 - Add BPF selftests for kfuncs from multiple modules, checking that the
   correct kfuncs are called (Simon Sundberg)

 - Ensure that internal and user-facing bpf_redirect flags don't overlap
   (Toke Høiland-Jørgensen)

 - Switch to use kvzmalloc to allocate BPF verifier environment (Rik van
   Riel)

 - Use raw_spinlock_t in BPF ringbuf to fix a sleep in atomic splat
   under RT (Wander Lairson Costa)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (38 commits)
  lib/buildid: Handle memfd_secret() files in build_id_parse()
  selftests/bpf: Add test case for delta propagation
  bpf: Fix print_reg_state's constant scalar dump
  bpf: Fix incorrect delta propagation between linked registers
  bpf: Properly test iter/task tid filtering
  bpf: Fix iter/task tid filtering
  riscv, bpf: Make BPF_CMPXCHG fully ordered
  bpf, vsock: Drop static vsock_bpf_prot initialization
  vsock: Update msg_count on read_skb()
  vsock: Update rx_bytes on read_skb()
  bpf, sockmap: SK_DROP on attempted redirects of unsupported af_vsock
  selftests/bpf: Add asserts for netfilter link info
  bpf: Fix link info netfilter flags to populate defrag flag
  selftests/bpf: Add test for sign extension in coerce_subreg_to_size_sx()
  selftests/bpf: Add test for truncation after sign extension in coerce_reg_to_size_sx()
  bpf: Fix truncation bug in coerce_reg_to_size_sx()
  selftests/bpf: Assert link info uprobe_multi count & path_size if unset
  bpf: Fix unpopulated path_size when uprobe_multi fields unset
  selftests/bpf: Fix cross-compiling urandom_read
  selftests/bpf: Add test for kfunc module order
  ...
2024-10-18 16:27:14 -07:00
Daniel Borkmann db123e4230 selftests/bpf: Add test case for delta propagation
Add a small BPF verifier test case to ensure that alu32 additions to
registers are not subject to linked scalar delta tracking.

  # ./vmtest.sh -- ./test_progs -t verifier_linked_scalars
  [...]
  ./test_progs -t verifier_linked_scalars
  [    1.413138] tsc: Refined TSC clocksource calibration: 3407.993 MHz
  [    1.413524] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x311fcd52370, max_idle_ns: 440795242006 ns
  [    1.414223] clocksource: Switched to clocksource tsc
  [    1.419640] bpf_testmod: loading out-of-tree module taints kernel.
  [    1.420025] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  #500/1   verifier_linked_scalars/scalars: find linked scalars:OK
  #500     verifier_linked_scalars:OK
  Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED
  [    1.590858] ACPI: PM: Preparing to enter system sleep state S5
  [    1.591402] reboot: Power down
  [...]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20241016134913.32249-3-daniel@iogearbox.net
2024-10-17 11:06:34 -07:00
Dimitar Kanaliev 35ccd576a2 selftests/bpf: Add test for sign extension in coerce_subreg_to_size_sx()
Add a test for unsigned ranges after signed extension instruction. This
case isn't currently covered by existing tests in verifier_movsx.c.

Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Dimitar Kanaliev <dimitar.kanaliev@siteground.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20241014121155.92887-4-dimitar.kanaliev@siteground.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-10-15 11:16:25 -07:00
Dimitar Kanaliev 61f506eacc selftests/bpf: Add test for truncation after sign extension in coerce_reg_to_size_sx()
Add test that checks whether unsigned ranges deduced by the verifier for
sign extension instruction is correct. Without previous patch that
fixes truncation in coerce_reg_to_size_sx() this test fails.

Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Dimitar Kanaliev <dimitar.kanaliev@siteground.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20241014121155.92887-3-dimitar.kanaliev@siteground.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-10-15 11:16:25 -07:00
Simon Sundberg f91b256644 selftests/bpf: Add test for kfunc module order
Add a test case for kfuncs from multiple external modules, checking
that the correct kfuncs are called regardless of which order they're
called in. Specifically, check that calling the kfuncs in an order
different from the one the modules' BTF are loaded in works.

Signed-off-by: Simon Sundberg <simon.sundberg@kau.se>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20241010-fix-kfunc-btf-caching-for-modules-v2-3-745af6c1af98@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-10-10 10:44:03 -07:00
Hou Tao c456f08040 selftests/bpf: Add more test case for field flattening
Add three success test cases to test the flattening of array of nested
struct. For these three tests, the number of special fields in map is
BTF_FIELDS_MAX, but the array is defined in structs with different
nested level.

Add one failure test case for the flattening as well. In the test case,
the number of special fields in map is BTF_FIELDS_MAX + 1. It will make
btf_parse_fields() in map_create() return -E2BIG, the creation of map
will succeed, but the load of program will fail because the btf_record
is invalid for the map.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20241008071114.3718177-3-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-10-09 16:32:47 -07:00
Al Viro 5f60d5f6bb move asm/unaligned.h to linux/unaligned.h
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-10-02 17:23:23 -04:00
Florian Kauer 49ebeb0c15 bpf: selftests: send packet to devmap redirect XDP
The current xdp_devmap_attach test attaches a program
that redirects to another program via devmap.

It is, however, never executed, so do that to catch
any bugs that might occur during execution.

Also, execute the same for a veth pair so that we
also cover the non-generic path.

Warning: Running this without the bugfix in this series
will likely crash your system.

Signed-off-by: Florian Kauer <florian.kauer@linutronix.de>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20240911-devel-koalo-fix-ingress-ifindex-v4-2-5c643ae10258@linutronix.de
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-10-02 13:51:43 -07:00
Eduard Zingerman a41b3828ec selftests/bpf: Verify that sync_linked_regs preserves subreg_def
This test was added because of a bug in verifier.c:sync_linked_regs(),
upon range propagation it destroyed subreg_def marks for registers.
The test is written in a way to return an upper half of a register
that is affected by range propagation and must have it's subreg_def
preserved. This gives a return value of 0 and leads to undefined
return value if subreg_def mark is not preserved.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240924210844.1758441-2-eddyz87@gmail.com
2024-10-01 17:19:04 +02:00
Linus Torvalds 440b652328 Merge tag 'bpf-next-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:

 - Introduce '__attribute__((bpf_fastcall))' for helpers and kfuncs with
   corresponding support in LLVM.

   It is similar to existing 'no_caller_saved_registers' attribute in
   GCC/LLVM with a provision for backward compatibility. It allows
   compilers generate more efficient BPF code assuming the verifier or
   JITs will inline or partially inline a helper/kfunc with such
   attribute. bpf_cast_to_kern_ctx, bpf_rdonly_cast,
   bpf_get_smp_processor_id are the first set of such helpers.

 - Harden and extend ELF build ID parsing logic.

   When called from sleepable context the relevants parts of ELF file
   will be read to find and fetch .note.gnu.build-id information. Also
   harden the logic to avoid TOCTOU, overflow, out-of-bounds problems.

 - Improvements and fixes for sched-ext:
    - Allow passing BPF iterators as kfunc arguments
    - Make the pointer returned from iter_next method trusted
    - Fix x86 JIT convergence issue due to growing/shrinking conditional
      jumps in variable length encoding

 - BPF_LSM related:
    - Introduce few VFS kfuncs and consolidate them in
      fs/bpf_fs_kfuncs.c
    - Enforce correct range of return values from certain LSM hooks
    - Disallow attaching to other LSM hooks

 - Prerequisite work for upcoming Qdisc in BPF:
    - Allow kptrs in program provided structs
    - Support for gen_epilogue in verifier_ops

 - Important fixes:
    - Fix uprobe multi pid filter check
    - Fix bpf_strtol and bpf_strtoul helpers
    - Track equal scalars history on per-instruction level
    - Fix tailcall hierarchy on x86 and arm64
    - Fix signed division overflow to prevent INT_MIN/-1 trap on x86
    - Fix get kernel stack in BPF progs attached to tracepoint:syscall

 - Selftests:
    - Add uprobe bench/stress tool
    - Generate file dependencies to drastically improve re-build time
    - Match JIT-ed and BPF asm with __xlated/__jited keywords
    - Convert older tests to test_progs framework
    - Add support for RISC-V
    - Few fixes when BPF programs are compiled with GCC-BPF backend
      (support for GCC-BPF in BPF CI is ongoing in parallel)
    - Add traffic monitor
    - Enable cross compile and musl libc

* tag 'bpf-next-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (260 commits)
  btf: require pahole 1.21+ for DEBUG_INFO_BTF with default DWARF version
  btf: move pahole check in scripts/link-vmlinux.sh to lib/Kconfig.debug
  btf: remove redundant CONFIG_BPF test in scripts/link-vmlinux.sh
  bpf: Call the missed kfree() when there is no special field in btf
  bpf: Call the missed btf_record_free() when map creation fails
  selftests/bpf: Add a test case to write mtu result into .rodata
  selftests/bpf: Add a test case to write strtol result into .rodata
  selftests/bpf: Rename ARG_PTR_TO_LONG test description
  selftests/bpf: Fix ARG_PTR_TO_LONG {half-,}uninitialized test
  bpf: Zero former ARG_PTR_TO_{LONG,INT} args in case of error
  bpf: Improve check_raw_mode_ok test for MEM_UNINIT-tagged types
  bpf: Fix helper writes to read-only maps
  bpf: Remove truncation test in bpf_strtol and bpf_strtoul helpers
  bpf: Fix bpf_strtol and bpf_strtoul helpers for 32bit
  selftests/bpf: Add tests for sdiv/smod overflow cases
  bpf: Fix a sdiv overflow issue
  libbpf: Add bpf_object__token_fd accessor
  docs/bpf: Add missing BPF program types to docs
  docs/bpf: Add constant values for linkages
  bpf: Use fake pt_regs when doing bpf syscall tracepoint tracing
  ...
2024-09-21 09:27:50 -07:00
Daniel Borkmann 211bf9cf17 selftests/bpf: Add a test case to write mtu result into .rodata
Add a test which attempts to call bpf_check_mtu() and writes the MTU
into .rodata section of the BPF program, and for comparison this adds
test cases also for .bss and .data section again. The bpf_check_mtu()
is a bit more special in that the passed mtu argument is read and
written by the helper (instead of just written to). Assert that writes
into .rodata remain rejected by the verifier.

  # ./vmtest.sh -- ./test_progs -t verifier_const
  [...]
  ./test_progs -t verifier_const
  [    1.657367] bpf_testmod: loading out-of-tree module taints kernel.
  [    1.657773] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  #473/1   verifier_const/rodata/strtol: write rejected:OK
  #473/2   verifier_const/bss/strtol: write accepted:OK
  #473/3   verifier_const/data/strtol: write accepted:OK
  #473/4   verifier_const/rodata/mtu: write rejected:OK
  #473/5   verifier_const/bss/mtu: write accepted:OK
  #473/6   verifier_const/data/mtu: write accepted:OK
  #473     verifier_const:OK
  [...]
  Summary: 2/10 PASSED, 0 SKIPPED, 0 FAILED

For comparison, without the MEM_UNINIT on bpf_check_mtu's proto:

  # ./vmtest.sh -- ./test_progs -t verifier_const
  [...]
  #473/3   verifier_const/data/strtol: write accepted:OK
  run_subtest:PASS:obj_open_mem 0 nsec
  run_subtest:FAIL:unexpected_load_success unexpected success: 0
  #473/4   verifier_const/rodata/mtu: write rejected:FAIL
  #473/5   verifier_const/bss/mtu: write accepted:OK
  #473/6   verifier_const/data/mtu: write accepted:OK
  #473     verifier_const:FAIL
  [...]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20240913191754.13290-9-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-13 13:17:56 -07:00
Daniel Borkmann 2e3f066020 selftests/bpf: Add a test case to write strtol result into .rodata
Add a test case which attempts to write into .rodata section of the
BPF program, and for comparison this adds test cases also for .bss
and .data section.

Before fix:

  # ./vmtest.sh -- ./test_progs -t verifier_const
  [...]
  ./test_progs -t verifier_const
  tester_init:PASS:tester_log_buf 0 nsec
  process_subtest:PASS:obj_open_mem 0 nsec
  process_subtest:PASS:specs_alloc 0 nsec
  run_subtest:PASS:obj_open_mem 0 nsec
  run_subtest:FAIL:unexpected_load_success unexpected success: 0
  #465/1   verifier_const/rodata: write rejected:FAIL
  #465/2   verifier_const/bss: write accepted:OK
  #465/3   verifier_const/data: write accepted:OK
  #465     verifier_const:FAIL
  [...]

After fix:

  # ./vmtest.sh -- ./test_progs -t verifier_const
  [...]
  ./test_progs -t verifier_const
  #465/1   verifier_const/rodata: write rejected:OK
  #465/2   verifier_const/bss: write accepted:OK
  #465/3   verifier_const/data: write accepted:OK
  #465     verifier_const:OK
  [...]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240913191754.13290-8-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-13 13:17:56 -07:00
Daniel Borkmann b073b82d4d selftests/bpf: Rename ARG_PTR_TO_LONG test description
Given we got rid of ARG_PTR_TO_LONG, change the test case description to
avoid potential confusion:

  # ./vmtest.sh -- ./test_progs -t verifier_int_ptr
  [...]
  ./test_progs -t verifier_int_ptr
  [    1.610563] bpf_testmod: loading out-of-tree module taints kernel.
  [    1.611049] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  #489/1   verifier_int_ptr/arg pointer to long uninitialized:OK
  #489/2   verifier_int_ptr/arg pointer to long half-uninitialized:OK
  #489/3   verifier_int_ptr/arg pointer to long misaligned:OK
  #489/4   verifier_int_ptr/arg pointer to long size < sizeof(long):OK
  #489/5   verifier_int_ptr/arg pointer to long initialized:OK
  #489     verifier_int_ptr:OK
  Summary: 1/5 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20240913191754.13290-7-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-13 13:17:56 -07:00
Daniel Borkmann b8e188f023 selftests/bpf: Fix ARG_PTR_TO_LONG {half-,}uninitialized test
The assumption of 'in privileged mode reads from uninitialized stack locations
are permitted' is not quite correct since the verifier was probing for read
access rather than write access. Both tests need to be annotated as __success
for privileged and unprivileged.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240913191754.13290-6-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-13 13:17:56 -07:00
Yonghong Song a18062d54a selftests/bpf: Add tests for sdiv/smod overflow cases
Subtests are added to exercise the patched code which handles
  - LLONG_MIN/-1
  - INT_MIN/-1
  - LLONG_MIN%-1
  - INT_MIN%-1
where -1 could be an immediate or in a register.
Without the previous patch, all these cases will crash the kernel on
x86_64 platform.

Additional tests are added to use small values (e.g. -5/-1, 5%-1, etc.)
in order to exercise the additional logic with patched insns.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240913150332.1188102-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-13 13:08:06 -07:00
Yonghong Song 2897b1e2a2 selftests/bpf: Fix arena_atomics failure due to llvm change
llvm change [1] made a change such that __sync_fetch_and_{and,or,xor}()
will generate atomic_fetch_*() insns even if the return value is not used.
This is a deliberate choice to make sure barrier semantics are preserved
from source code to asm insn.

But the change in [1] caused arena_atomics selftest failure.

  test_arena_atomics:PASS:arena atomics skeleton open 0 nsec
  libbpf: prog 'and': BPF program load failed: Permission denied
  libbpf: prog 'and': -- BEGIN PROG LOAD LOG --
  arg#0 reference type('UNKNOWN ') size cannot be determined: -22
  0: R1=ctx() R10=fp0
  ; if (pid != (bpf_get_current_pid_tgid() >> 32)) @ arena_atomics.c:87
  0: (18) r1 = 0xffffc90000064000       ; R1_w=map_value(map=arena_at.bss,ks=4,vs=4)
  2: (61) r6 = *(u32 *)(r1 +0)          ; R1_w=map_value(map=arena_at.bss,ks=4,vs=4) R6_w=scalar(smin=0,smax=umax=0xffffffff,v
ar_off=(0x0; 0xffffffff))
  3: (85) call bpf_get_current_pid_tgid#14      ; R0_w=scalar()
  4: (77) r0 >>= 32                     ; R0_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff))
  5: (5d) if r0 != r6 goto pc+11        ; R0_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R6_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0x)
  ; __sync_fetch_and_and(&and64_value, 0x011ull << 32); @ arena_atomics.c:91
  6: (18) r1 = 0x100000000060           ; R1_w=scalar()
  8: (bf) r1 = addr_space_cast(r1, 0, 1)        ; R1_w=arena
  9: (18) r2 = 0x1100000000             ; R2_w=0x1100000000
  11: (db) r2 = atomic64_fetch_and((u64 *)(r1 +0), r2)
  BPF_ATOMIC stores into R1 arena is not allowed
  processed 9 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --
  libbpf: prog 'and': failed to load: -13
  libbpf: failed to load object 'arena_atomics'
  libbpf: failed to load BPF skeleton 'arena_atomics': -13
  test_arena_atomics:FAIL:arena atomics skeleton load unexpected error: -13 (errno 13)
  #3       arena_atomics:FAIL

The reason of the failure is due to [2] where atomic{64,}_fetch_{and,or,xor}() are not
allowed by arena addresses.

Version 2 of the patch fixed the issue by using inline asm ([3]). But further discussion
suggested to find a way from source to generate locked insn which is more user
friendly. So in not-merged llvm patch ([4]), if relax memory ordering is used and
the return value is not used, locked insn could be generated.

So with llvm patch [4] to compile the bpf selftest, the following code
  __c11_atomic_fetch_and(&and64_value, 0x011ull << 32, memory_order_relaxed);
is able to generate locked insn, hence fixing the selftest failure.

  [1] https://github.com/llvm/llvm-project/pull/106494
  [2] d503a04f8b ("bpf: Add support for certain atomics in bpf_arena to x86 JIT")
  [3] https://lore.kernel.org/bpf/20240803025928.4184433-1-yonghong.song@linux.dev/
  [4] https://github.com/llvm/llvm-project/pull/107343

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240909223431.1666305-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-11 10:07:10 -07:00
Andrii Nakryiko 3c217a1820 selftests/bpf: add build ID tests
Add a new set of tests validating behavior of capturing stack traces
with build ID. We extend uprobe_multi target binary with ability to
trigger uprobe (so that we can capture stack traces from it), but also
we allow to force build ID data to be either resident or non-resident in
memory (see also a comment about quirks of MADV_PAGEOUT).

That way we can validate that in non-sleepable context we won't get
build ID (as expected), but with sleepable uprobes we will get that
build ID regardless of it being physically present in memory.

Also, we add a small add-on linker script which reorders
.note.gnu.build-id section and puts it after (big) .text section,
putting build ID data outside of the very first page of ELF file. This
will test all the relaxations we did in build ID parsing logic in kernel
thanks to freader abstraction.

Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-11-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-11 09:58:31 -07:00
Philo Lu 83dff60171 selftests/bpf: Expand skb dynptr selftests for tp_btf
Add 3 test cases for skb dynptr used in tp_btf:
- test_dynptr_skb_tp_btf: use skb dynptr in tp_btf and make sure it is
  read-only.
- skb_invalid_ctx_fentry/skb_invalid_ctx_fexit: bpf_dynptr_from_skb
  should fail in fentry/fexit.

In test_dynptr_skb_tp_btf, to trigger the tracepoint in kfree_skb,
test_pkt_access is used for its test_run, as in kfree_skb.c. Because the
test process is different from others, a new setup type is defined,
i.e., SETUP_SKB_PROG_TP.

The result is like:
$ ./test_progs -t 'dynptr/test_dynptr_skb_tp_btf'
  #84/14   dynptr/test_dynptr_skb_tp_btf:OK
  #84      dynptr:OK
  #127     kfunc_dynptr_param:OK
  Summary: 2/1 PASSED, 0 SKIPPED, 0 FAILED

$ ./test_progs -t 'dynptr/skb_invalid_ctx_f'
  #84/85   dynptr/skb_invalid_ctx_fentry:OK
  #84/86   dynptr/skb_invalid_ctx_fexit:OK
  #84      dynptr:OK
  #127     kfunc_dynptr_param:OK
  Summary: 2/2 PASSED, 0 SKIPPED, 0 FAILED

Also fix two coding style nits (change spaces to tabs).

Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240911033719.91468-6-lulie@linux.alibaba.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-09-11 08:57:54 -07:00
Philo Lu 2060f07f86 selftests/bpf: Add test for __nullable suffix in tp_btf
Add a tracepoint with __nullable suffix in bpf_testmod, and add cases
for it:

$ ./test_progs -t "tp_btf_nullable"
 #406/1   tp_btf_nullable/handle_tp_btf_nullable_bare1:OK
 #406/2   tp_btf_nullable/handle_tp_btf_nullable_bare2:OK
 #406     tp_btf_nullable:OK
 Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240911033719.91468-3-lulie@linux.alibaba.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-09-11 08:56:42 -07:00
Maxim Mikityanskiy bee109b7b3 bpf: Fix error message on kfunc arg type mismatch
When "arg#%d expected pointer to ctx, but got %s" error is printed, both
template parts actually point to the type of the argument, therefore, it
will also say "but got PTR", regardless of what was the actual register
type.

Fix the message to print the register type in the second part of the
template, change the existing test to adapt to the new format, and add a
new test to test the case when arg is a pointer to context, but reg is a
scalar.

Fixes: 00b85860fe ("bpf: Rewrite kfunc argument handling")
Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/bpf/20240909133909.1315460-1-maxim@isovalent.com
2024-09-09 15:58:17 -07:00
JP Kobryn 1b3bc648f5 bpf/selftests: coverage for tp and perf event progs using kfuncs
This coverage ensures that kfuncs are allowed within tracepoint and perf
event programs.

Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Link: https://lore.kernel.org/r/20240905223812.141857-3-inwardvessel@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-05 17:02:03 -07:00
Pu Lehui a48a43884c selftests/bpf: Rename fallback in bpf_dctcp to avoid naming conflict
Recently, when compiling bpf selftests on RV64, the following
compilation failure occurred:

progs/bpf_dctcp.c:29:21: error: redefinition of 'fallback' as different kind of symbol
   29 | volatile const char fallback[TCP_CA_NAME_MAX];
      |                     ^
/workspace/tools/testing/selftests/bpf/tools/include/vmlinux.h:86812:15: note: previous definition is here
 86812 | typedef u32 (*fallback)(u32, const unsigned char *, size_t);

The reason is that the `fallback` symbol has been defined in
arch/riscv/lib/crc32.c, which will cause symbol conflicts when vmlinux.h
is included in bpf_dctcp. Let we rename `fallback` string to
`fallback_cc` in bpf_dctcp to fix this compilation failure.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20240905081401.1894789-3-pulehui@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-05 13:13:39 -07:00
Lin Yikai 5db0ba6766 selftests/bpf: fix some typos in selftests
Hi, fix some spelling errors in selftest, the details are as follows:

-in the codes:
	test_bpf_sk_stoarge_map_iter_fd(void)
		->test_bpf_sk_storage_map_iter_fd(void)
	load BTF from btf_data.o->load BTF from btf_data.bpf.o

-in the code comments:
	preample->preamble
	multi-contollers->multi-controllers
	errono->errno
	unsighed/unsinged->unsigned
	egree->egress
	shoud->should
	regsiter->register
	assummed->assumed
	conditiona->conditional
	rougly->roughly
	timetamp->timestamp
	ingores->ignores
	null-termainted->null-terminated
	slepable->sleepable
	implemenation->implementation
	veriables->variables
	timetamps->timestamps
	substitue a costant->substitute a constant
	secton->section
	unreferened->unreferenced
	verifer->verifier
	libppf->libbpf
...

Signed-off-by: Lin Yikai <yikai.lin@vivo.com>
Link: https://lore.kernel.org/r/20240905110354.3274546-1-yikai.lin@vivo.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-05 13:07:47 -07:00
Jiri Olsa 8df43e8594 selftests/bpf: Add uprobe multi pid filter test for fork-ed processes
The idea is to create and monitor 3 uprobes, each trigered in separate
process and make sure the bpf program gets executed just for the proper
PID specified via pid filter.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240905115124.1503998-4-jolsa@kernel.org
2024-09-05 12:43:22 -07:00
Pu Lehui 4a4c4c0d0a selftests/bpf: Enable test_bpf_syscall_macro: Syscall_arg1 on s390 and arm64
Considering that CO-RE direct read access to the first system call
argument is already available on s390 and arm64, let's enable
test_bpf_syscall_macro:syscall_arg1 on these architectures.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240831041934.1629216-4-pulehui@huaweicloud.com
2024-09-04 17:06:09 -07:00
Yonghong Song eff5b5fffc selftests/bpf: Add a selftest for x86 jit convergence issues
The core part of the selftest, i.e., the je <-> jmp cycle, mimics the
original sched-ext bpf program. The test will fail without the
previous patch.

I tried to create some cases for other potential cycles
(je <-> je, jmp <-> je and jmp <-> jmp) with similar pattern
to the test in this patch, but failed. So this patch
only contains one test for je <-> jmp cycle.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240904221256.37389-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-09-04 16:46:22 -07:00
Feng Yang 23457b37ec selftests: bpf: Replace sizeof(arr)/sizeof(arr[0]) with ARRAY_SIZE
The ARRAY_SIZE macro is more compact and more formal in linux source.

Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240903072559.292607-1-yangfeng59949@163.com
2024-09-04 12:58:46 -07:00
Juntong Deng 7c5f7b16fe selftests/bpf: Add tests for iter next method returning valid pointer
This patch adds test cases for iter next method returning valid
pointer, which can also used as usage examples.

Currently iter next method should return valid pointer.

iter_next_trusted is the correct usage and test if iter next method
return valid pointer. bpf_iter_task_vma_next has KF_RET_NULL flag,
so the returned pointer may be NULL. We need to check if the pointer
is NULL before using it.

iter_next_trusted_or_null is the incorrect usage. There is no checking
before using the pointer, so it will be rejected by the verifier.

iter_next_rcu and iter_next_rcu_or_null are similar test cases for
KF_RCU_PROTECTED iterators.

iter_next_rcu_not_trusted is used to test that the pointer returned by
iter next method of KF_RCU_PROTECTED iterator cannot be passed in
KF_TRUSTED_ARGS kfuncs.

iter_next_ptr_mem_not_trusted is used to test that base type
PTR_TO_MEM should not be combined with type flag PTR_TRUSTED.

Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Link: https://lore.kernel.org/r/AM6PR03MB5848709758F6922F02AF9F1F99962@AM6PR03MB5848.eurprd03.prod.outlook.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-29 18:52:16 -07:00
Martin KaFai Lau cada0bdcc4 selftests/bpf: Test epilogue patching when the main prog has multiple BPF_EXIT
This patch tests the epilogue patching when the main prog has
multiple BPF_EXIT. The verifier should have patched the 2nd (and
later) BPF_EXIT with a BPF_JA that goes back to the earlier
patched epilogue instructions.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-10-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-29 18:15:45 -07:00
Martin KaFai Lau 42fdbbde6c selftests/bpf: A pro/epilogue test when the main prog jumps back to the 1st insn
This patch adds a pro/epilogue test when the main prog has a goto insn
that goes back to the very first instruction of the prog. It is
to test the correctness of the adjust_jmp_off(prog, 0, delta)
after the verifier has applied the prologue and/or epilogue patch.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-9-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-29 18:15:45 -07:00
Martin KaFai Lau b191b0fd74 selftests/bpf: Add tailcall epilogue test
This patch adds a gen_epilogue test to test a main prog
using a bpf_tail_call.

A non test_loader test is used. The tailcall target program,
"test_epilogue_subprog", needs to be used in a struct_ops map
before it can be loaded. Another struct_ops map is also needed
to host the actual "test_epilogue_tailcall" struct_ops program
that does the bpf_tail_call. The earlier test_loader patch
will attach all struct_ops maps but the bpf_testmod.c does
not support >1 attached struct_ops.

The earlier patch used the test_loader which has already covered
checking for the patched pro/epilogue instructions. This is done
by the __xlated tag.

This patch goes for the regular skel load and syscall test to do
the tailcall test that can also allow to directly pass the
the "struct st_ops_args *args" as ctx_in to the
SEC("syscall") program.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-8-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-29 18:15:45 -07:00
Martin KaFai Lau 47e69431b5 selftests/bpf: Test gen_prologue and gen_epilogue
This test adds a new struct_ops "bpf_testmod_st_ops" in bpf_testmod.
The ops of the bpf_testmod_st_ops is triggered by new kfunc calls
"bpf_kfunc_st_ops_test_*logue". These new kfunc calls are
primarily used by the SEC("syscall") program. The test triggering
sequence is like:
    SEC("syscall")
    syscall_prologue(struct st_ops_args *args)
        bpf_kfunc_st_op_test_prologue(args)
	    st_ops->test_prologue(args)

.gen_prologue adds 1000 to args->a
.gen_epilogue adds 10000 to args->a
.gen_epilogue will also set the r0 to 2 * args->a.

The .gen_prologue and .gen_epilogue of the bpf_testmod_st_ops
will test the prog->aux->attach_func_name to decide if
it needs to generate codes.

The main programs of the pro_epilogue.c will call a
new kfunc bpf_kfunc_st_ops_inc10 which does "args->a += 10".
It will also call a subprog() which does "args->a += 1".

This patch uses the test_loader infra to check the __xlated
instructions patched after gen_prologue and/or gen_epilogue.
The __xlated check is based on Eduard's example (Thanks!) in v1.

args->a is returned by the struct_ops prog (either the main prog
or the epilogue). Thus, the __retval of the SEC("syscall") prog
is checked. For example, when triggering the ops in the
'SEC("struct_ops/test_epilogue") int test_epilogue'
The expected args->a is +1 (subprog call) + 10 (kfunc call)
    	     	     	+ 10000 (.gen_epilogue) = 10011.
The expected return value is 2 * 10011 (.gen_epilogue).

Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-7-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-29 18:15:45 -07:00
Amery Hung bd0b4836a2 selftests/bpf: Make sure stashed kptr in local kptr is freed recursively
When dropping a local kptr, any kptr stashed into it is supposed to be
freed through bpf_obj_free_fields->__bpf_obj_drop_impl recursively. Add a
test to make sure it happens.

The test first stashes a referenced kptr to "struct task" into a local
kptr and gets the reference count of the task. Then, it drops the local
kptr and reads the reference count of the task again. Since
bpf_obj_free_fields and __bpf_obj_drop_impl will go through the local kptr
recursively during bpf_obj_drop, the dtor of the stashed task kptr should
eventually be called. The second reference count should be one less than
the first one.

Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240827011301.608620-1-amery.hung@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-29 12:18:26 -07:00
Juntong Deng 6db59c4935 selftests/bpf: Add test for zero offset or non-zero offset pointers as KF_ACQUIRE kfuncs argument
This patch adds test cases for zero offset (implicit cast) or non-zero
offset pointer as KF_ACQUIRE kfuncs argument. Currently KF_ACQUIRE
kfuncs should support passing in pointers like &sk->sk_write_queue
(non-zero offset) or &sk->__sk_common (zero offset) and not be rejected
by the verifier.

Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Link: https://lore.kernel.org/r/AM6PR03MB5848CB6F0D4D9068669A905B99952@AM6PR03MB5848.eurprd03.prod.outlook.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-28 17:11:54 -07:00
Jakub Kicinski e540e3bcf2 Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2024-08-23

We've added 10 non-merge commits during the last 15 day(s) which contain
a total of 10 files changed, 222 insertions(+), 190 deletions(-).

The main changes are:

1) Add TCP_BPF_SOCK_OPS_CB_FLAGS to bpf_*sockopt() to address the case
   when long-lived sockets miss a chance to set additional callbacks
   if a sockops program was not attached early in their lifetime,
   from Alan Maguire.

2) Add a batch of BPF selftest improvements which fix a few bugs and add
   missing features to improve the test coverage of sockmap/sockhash,
   from Michal Luczaj.

3) Fix a false-positive Smatch-reported off-by-one in tcp_validate_cookie()
   which is part of the test_tcp_custom_syncookie BPF selftest,
   from Kuniyuki Iwashima.

4) Fix the flow_dissector BPF selftest which had a bug in IP header's
   tot_len calculation doing subtraction after htons() instead of inside
   htons(), from Asbjørn Sloth Tønnesen.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
  selftest: bpf: Remove mssind boundary check in test_tcp_custom_syncookie.c.
  selftests/bpf: Introduce __attribute__((cleanup)) in create_pair()
  selftests/bpf: Exercise SOCK_STREAM unix_inet_redir_to_connected()
  selftests/bpf: Honour the sotype of af_unix redir tests
  selftests/bpf: Simplify inet_socketpair() and vsock_socketpair_connectible()
  selftests/bpf: Socket pair creation, cleanups
  selftests/bpf: Support more socket types in create_pair()
  selftests/bpf: Avoid subtraction after htons() in ipip tests
  selftests/bpf: add sockopt tests for TCP_BPF_SOCK_OPS_CB_FLAGS
  bpf/bpf_get,set_sockopt: add option to set TCP-BPF sock ops flags
====================

Link: https://patch.msgid.link/20240823134959.1091-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-26 08:50:29 -07:00
Jordan Rome ddc3d98807 selftests/bpf: Add tests for bpf_copy_from_user_str kfunc.
This adds tests for both the happy path and
the error path.

Signed-off-by: Jordan Rome <linux@jordanrome.com>
Link: https://lore.kernel.org/r/20240823195101.3621028-2-linux@jordanrome.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-23 15:40:11 -07:00
Dave Marchevsky 91c96842ab selftests/bpf: Test bpf_kptr_xchg stashing into local kptr
Test stashing both referenced kptr and local kptr into local kptrs. Then,
test unstashing them.

Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Link: https://lore.kernel.org/r/20240813212424.2871455-6-amery.hung@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-23 11:39:33 -07:00
Andrii Nakryiko f727b13dbe selftests/bpf: add multi-uprobe benchmarks
Add multi-uprobe and multi-uretprobe benchmarks to bench tool.
Multi- and classic uprobes/uretprobes have different low-level
triggering code paths, so it's sometimes important to be able to
benchmark both flavors of uprobes/uretprobes.

Sample examples from my dev machine below. Single-threaded peformance
almost doesn't differ, but with more parallel CPUs triggering the same
uprobe/uretprobe the difference grows. This might be due to [0], but
given the code is slightly different, there could be other sources of
slowdown.

Note, all these numbers will change due to ongoing work to improve
uprobe/uretprobe scalability (e.g., [1]), but having benchmark like this
is useful for measurements and debugging nevertheless.

\#!/bin/bash
set -eufo pipefail
for p in 1 8 16 32; do
    for i in uprobe-nop uretprobe-nop uprobe-multi-nop uretprobe-multi-nop; do
        summary=$(sudo ./bench -w1 -d3 -p$p -a trig-$i | tail -n1)
        total=$(echo "$summary" | cut -d'(' -f1 | cut -d' ' -f3-)
        percpu=$(echo "$summary" | cut -d'(' -f2 | cut -d')' -f1 | cut -d'/' -f1)
        printf "%-21s (%2d cpus): %s (%s/s/cpu)\n" $i $p "$total" "$percpu"
    done
    echo
done

uprobe-nop            ( 1 cpus):    1.020 ± 0.005M/s  (  1.020M/s/cpu)
uretprobe-nop         ( 1 cpus):    0.515 ± 0.009M/s  (  0.515M/s/cpu)
uprobe-multi-nop      ( 1 cpus):    1.036 ± 0.004M/s  (  1.036M/s/cpu)
uretprobe-multi-nop   ( 1 cpus):    0.512 ± 0.005M/s  (  0.512M/s/cpu)

uprobe-nop            ( 8 cpus):    3.481 ± 0.030M/s  (  0.435M/s/cpu)
uretprobe-nop         ( 8 cpus):    2.222 ± 0.008M/s  (  0.278M/s/cpu)
uprobe-multi-nop      ( 8 cpus):    3.769 ± 0.094M/s  (  0.471M/s/cpu)
uretprobe-multi-nop   ( 8 cpus):    2.482 ± 0.007M/s  (  0.310M/s/cpu)

uprobe-nop            (16 cpus):    2.968 ± 0.011M/s  (  0.185M/s/cpu)
uretprobe-nop         (16 cpus):    1.870 ± 0.002M/s  (  0.117M/s/cpu)
uprobe-multi-nop      (16 cpus):    3.541 ± 0.037M/s  (  0.221M/s/cpu)
uretprobe-multi-nop   (16 cpus):    2.123 ± 0.026M/s  (  0.133M/s/cpu)

uprobe-nop            (32 cpus):    2.524 ± 0.026M/s  (  0.079M/s/cpu)
uretprobe-nop         (32 cpus):    1.572 ± 0.003M/s  (  0.049M/s/cpu)
uprobe-multi-nop      (32 cpus):    2.717 ± 0.003M/s  (  0.085M/s/cpu)
uretprobe-multi-nop   (32 cpus):    1.687 ± 0.007M/s  (  0.053M/s/cpu)

  [0] https://lore.kernel.org/linux-trace-kernel/20240805202803.1813090-1-andrii@kernel.org/
  [1] https://lore.kernel.org/linux-trace-kernel/20240731214256.3588718-1-andrii@kernel.org/

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20240806042935.3867862-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-23 10:00:37 -07:00
Eduard Zingerman c52a1e6eb7 selftests/bpf: match both retq/rethunk in verifier_tailcall_jit
Depending on kernel parameters, x86 jit generates either retq or jump
to rethunk for 'exit' instruction. The difference could be seen when
kernel is booted with and without mitigations=off parameter.
Relax the verifier_tailcall_jit test case to match both variants.

Fixes: e5bdd6a8be ("selftests/bpf: validate jit behaviour for tail calls")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240823080644.263943-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-23 07:29:02 -07:00
Leon Hwang 7559a7a84e selftests/bpf: Add testcase for updating attached freplace prog to prog_array map
Add a selftest to confirm the issue, which gets -EINVAL when update
attached freplace prog to prog_array map, has been fixed.

cd tools/testing/selftests/bpf; ./test_progs -t tailcalls
328/25  tailcalls/tailcall_freplace:OK
328     tailcalls:OK
Summary: 1/25 PASSED, 0 SKIPPED, 0 FAILED

Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Link: https://lore.kernel.org/r/20240728114612.48486-3-leon.hwang@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-22 13:28:19 -07:00
Alexei Starovoitov 50c374c6d1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Cross-merge bpf fixes after downstream PR including
important fixes (from bpf-next point of view):
commit 41c24102af ("selftests/bpf: Filter out _GNU_SOURCE when compiling test_cpp")
commit fdad456cbc ("bpf: Fix updating attached freplace prog in prog_array map")

No conflicts.

Adjacent changes in:
include/linux/bpf_verifier.h
kernel/bpf/verifier.c
tools/testing/selftests/bpf/Makefile

Link: https://lore.kernel.org/bpf/20240813234307.82773-1-alexei.starovoitov@gmail.com/
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-22 09:48:44 -07:00
Eduard Zingerman 8c2e043daa selftests/bpf: check if bpf_fastcall is recognized for kfuncs
Use kfunc_bpf_cast_to_kern_ctx() and kfunc_bpf_rdonly_cast() to verify
that bpf_fastcall pattern is recognized for kfunc calls.

Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240822084112.3257995-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-22 08:35:21 -07:00
Eduard Zingerman adec67d372 selftests/bpf: rename nocsr -> bpf_fastcall in selftests
Attribute used by LLVM implementation of the feature had been changed
from no_caller_saved_registers to bpf_fastcall (see [1]).
This commit replaces references to nocsr by references to bpf_fastcall
to keep LLVM and selftests parts in sync.

[1] https://github.com/llvm/llvm-project/pull/105417

Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240822084112.3257995-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-22 08:35:20 -07:00
Kuniyuki Iwashima af8a066f1c selftest: bpf: Remove mssind boundary check in test_tcp_custom_syncookie.c.
Smatch reported a possible off-by-one in tcp_validate_cookie().

However, it's false positive because the possible range of mssind is
limited from 0 to 3 by the preceding calculation.

  mssind = (cookie & (3 << 6)) >> 6;

Now, the verifier does not complain without the boundary check.
Let's remove the checks.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/bpf/6ae12487-d3f1-488b-9514-af0dac96608f@stanley.mountain/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240821013425.49316-1-kuniyu@amazon.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-08-21 23:19:33 -07:00
Eduard Zingerman a038eacdbf selftests/bpf: validate __xlated same way as __jited
Both __xlated and __jited work with disassembly.
It is logical to have both work in a similar manner.

This commit updates __xlated macro handling in test_loader.c by making
it expect matches on sequential lines, same way as __jited operates.
For example:

    __xlated("1: *(u64 *)(r10 -16) = r1")      ;; matched on line N
    __xlated("3: r0 = &(void __percpu *)(r0)") ;; matched on line N+1

Also:

    __xlated("1: *(u64 *)(r10 -16) = r1")      ;; matched on line N
    __xlated("...")                            ;; not matched
    __xlated("3: r0 = &(void __percpu *)(r0)") ;; mantched on any
                                               ;; line >= N

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240820102357.3372779-10-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-21 11:03:01 -07:00
Eduard Zingerman e5bdd6a8be selftests/bpf: validate jit behaviour for tail calls
A program calling sub-program which does a tail call.
The idea is to verify instructions generated by jit for tail calls:
- in program and sub-program prologues;
- for subprogram call instruction;
- for tail call itself.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240820102357.3372779-9-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-21 11:03:01 -07:00
Eduard Zingerman 7d743e4c75 selftests/bpf: __jited test tag to check disassembly after jit
Allow to verify jit behaviour by writing tests as below:

    SEC("tp")
    __arch_x86_64
    __jited("   endbr64")
    __jited("   nopl    (%rax,%rax)")
    __jited("   xorq    %rax, %rax")
    ...
    __naked void some_test(void)
    {
        asm volatile (... ::: __clobber_all);
    }

Allow regular expressions in patterns, same way as in __msg.
By default assume that each __jited pattern has to be matched on the
next consecutive line of the disassembly, e.g.:

    __jited("   endbr64")             # matched on line N
    __jited("   nopl    (%rax,%rax)") # matched on line N+1

If match occurs on a wrong line an error is reported.
To override this behaviour use __jited("..."), e.g.:

    __jited("   endbr64")             # matched on line N
    __jited("...")                    # not matched
    __jited("   nopl    (%rax,%rax)") # matched on any line >= N

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240820102357.3372779-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-21 11:03:01 -07:00
Eduard Zingerman f8d161756d selftests/bpf: replace __regex macro with "{{...}}" patterns
Upcoming changes require a notation to specify regular expression
matches for regular verifier log messages, disassembly of BPF
instructions, disassembly of jited instructions.

Neither basic nor extended POSIX regular expressions w/o additional
escaping are good for this role because of wide use of special
characters in disassembly, for example:

    movq -0x10(%rbp), %rax  ;; () are special characters
    cmpq $0x21, %rax        ;; $ is a special character

    *(u64 *)(r10 -16) = r1  ;; * and () are special characters

This commit borrows syntax from LLVM's FileCheck utility.
It replaces __regex macro with ability to embed regular expressions
in __msg patters using "{{" "}}" pairs for escaping.
Syntax for __msg patterns:

    pattern := (<verbatim text> | regex)*
    regex := "{{" <posix extended regular expression> "}}"

For example, pattern "foo{{[0-9]+}}" matches strings like
"foo0", "foo007", etc.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240820102357.3372779-5-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-21 11:03:00 -07:00
Eduard Zingerman f00bb757ed selftests/bpf: fix to avoid __msg tag de-duplication by clang
__msg, __regex and __xlated tags are based on
__attribute__((btf_decl_tag("..."))) annotations.

Clang de-duplicates such annotations, e.g. the following
two sequences of tags are identical in final BTF:

    /* seq A */            /* seq B */
    __tag("foo")           __tag("foo")
    __tag("bar")           __tag("bar")
    __tag("foo")

Fix this by adding a unique suffix for each tag using __COUNTER__
pre-processor macro. E.g. here is a new definition for __msg:

    #define __msg(msg) \
      __attribute__((btf_decl_tag("comment:test_expect_msg=" XSTR(__COUNTER__) "=" msg)))

Using this definition the "seq A" from example above is translated to
BTF as follows:

    [..] DECL_TAG 'comment:test_expect_msg=0=foo' type_id=X component_idx=-1
    [..] DECL_TAG 'comment:test_expect_msg=1=bar' type_id=X component_idx=-1
    [..] DECL_TAG 'comment:test_expect_msg=2=foo' type_id=X component_idx=-1

Surprisingly, this bug affects a single existing test:
verifier_spill_fill/old_stack_misc_vs_cur_ctx_ptr,
where sequence of identical messages was expected in the log.

Fixes: 537c3f66ea ("selftests/bpf: add generic BPF program tester-loader")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240820102357.3372779-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-21 11:03:00 -07:00
Andrii Nakryiko b0cd726f9a selftests/bpf: test passing iterator to a kfunc
Define BPF iterator "getter" kfunc, which accepts iterator pointer as
one of the arguments. Make sure that argument passed doesn't have to be
the very first argument (unlike new-next-destroy combo).

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240808232230.2848712-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-08-21 10:37:52 -07:00