linux.git/tools/testing/selftests/bpf, branch v6.9 Linux kernel source tree selftests/bpf: Test PROBE_MEM of VSYSCALL_ADDR on x86-64 2024-04-26T16:45:18+00:00 Puranjay Mohan puranjay@kernel.org 2024-04-24T10:02:10+00:00 7cd6750d9a560fa69bb640a7280479d6a67999ad The vsyscall is a legacy API for fast execution of system calls. It maps a page at address VSYSCALL_ADDR into the userspace program. This address is in the top 10MB of the address space: ffffffffff600000 - ffffffffff600fff | 4 kB | legacy vsyscall ABI The last commit fixes the x86-64 BPF JIT to skip accessing addresses in this memory region. Add this address to bpf_testmod_return_ptr() so we can make sure that it is fixed. After this change and without the previous commit, subprogs_extable selftest will crash the kernel. Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Link: https://lore.kernel.org/r/20240424100210.11982-4-puranjay@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
The vsyscall is a legacy API for fast execution of system calls. It maps
a page at address VSYSCALL_ADDR into the userspace program. This address
is in the top 10MB of the address space:

ffffffffff600000 - ffffffffff600fff |    4 kB | legacy vsyscall ABI

The last commit fixes the x86-64 BPF JIT to skip accessing addresses in
this memory region. Add this address to bpf_testmod_return_ptr() so we
can make sure that it is fixed.

After this change and without the previous commit, subprogs_extable
selftest will crash the kernel.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Link: https://lore.kernel.org/r/20240424100210.11982-4-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf: Check bloom filter map value size 2024-03-27T16:56:17+00:00 Andrei Matei andreimatei1@gmail.com 2024-03-27T02:42:44+00:00 a8d89feba7e54e691ca7c4efc2a6264fa83f3687 This patch adds a missing check to bloom filter creating, rejecting values above KMALLOC_MAX_SIZE. This brings the bloom map in line with many other map types. The lack of this protection can cause kernel crashes for value sizes that overflow int's. Such a crash was caught by syzkaller. The next patch adds more guard-rails at a lower level. Signed-off-by: Andrei Matei <andreimatei1@gmail.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240327024245.318299-2-andreimatei1@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
This patch adds a missing check to bloom filter creating, rejecting
values above KMALLOC_MAX_SIZE. This brings the bloom map in line with
many other map types.

The lack of this protection can cause kernel crashes for value sizes
that overflow int's. Such a crash was caught by syzkaller. The next
patch adds more guard-rails at a lower level.

Signed-off-by: Andrei Matei <andreimatei1@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240327024245.318299-2-andreimatei1@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
selftests/bpf: verifier_arena: fix mmap address for arm64 2024-03-23T03:37:39+00:00 Puranjay Mohan puranjay12@gmail.com 2024-03-22T13:35:52+00:00 fa3550dca8f02ec312727653a94115ef3ab68445 The arena_list selftest uses (1ull << 32) in the mmap address computation for arm64. Use the same in the verifier_arena selftest. This makes the selftest pass for arm64 on the CI[1]. [1] https://github.com/kernel-patches/bpf/pull/6622 Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Link: https://lore.kernel.org/r/20240322133552.70681-1-puranjay12@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
The arena_list selftest uses (1ull << 32) in the mmap address
computation for arm64. Use the same in the verifier_arena selftest.

This makes the selftest pass for arm64 on the CI[1].

[1] https://github.com/kernel-patches/bpf/pull/6622

Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Link: https://lore.kernel.org/r/20240322133552.70681-1-puranjay12@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
selftests/bpf: Add arena test case for 4Gbyte corner case 2024-03-15T21:24:06+00:00 Alexei Starovoitov ast@kernel.org 2024-03-15T02:18:34+00:00 a90c5845db958701ddc7659bc4f6db6fa647e449 Check that 4Gbyte arena can be allocated and overflow/underflow access in the first and the last page behaves as expected. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20240315021834.62988-5-alexei.starovoitov@gmail.com 
Check that 4Gbyte arena can be allocated and overflow/underflow access in
the first and the last page behaves as expected.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20240315021834.62988-5-alexei.starovoitov@gmail.com
selftests/bpf: Remove hard coded PAGE_SIZE macro. 2024-03-15T21:24:03+00:00 Alexei Starovoitov ast@kernel.org 2024-03-15T02:18:33+00:00 9a2d5a966b47e5657b22dfa257365b7ef2abc3c0 Remove hard coded PAGE_SIZE. Add #include <sys/user.h> instead (that works on x86-64 and s390) and fallback to slow getpagesize() for aarch64. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20240315021834.62988-4-alexei.starovoitov@gmail.com 
Remove hard coded PAGE_SIZE.
Add #include <sys/user.h> instead (that works on x86-64 and s390)
and fallback to slow getpagesize() for aarch64.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20240315021834.62988-4-alexei.starovoitov@gmail.com
libbpf, selftests/bpf: Adjust libbpf, bpftool, selftests to match LLVM 2024-03-15T21:24:00+00:00 Alexei Starovoitov ast@kernel.org 2024-03-15T02:18:32+00:00 10ebe835c937a11870690aa44c7c970fe906ff54 The selftests use to tell LLVM about special pointers. For LLVM there is nothing "arena" about them. They are simply pointers in a different address space. Hence LLVM diff https://github.com/llvm/llvm-project/pull/85161 renamed: . macro __BPF_FEATURE_ARENA_CAST -> __BPF_FEATURE_ADDR_SPACE_CAST . global variables in __attribute__((address_space(N))) are now placed in section named ".addr_space.N" instead of ".arena.N". Adjust libbpf, bpftool, and selftests to match LLVM. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20240315021834.62988-3-alexei.starovoitov@gmail.com 
The selftests use
to tell LLVM about special pointers. For LLVM there is nothing "arena"
about them. They are simply pointers in a different address space.
Hence LLVM diff https://github.com/llvm/llvm-project/pull/85161 renamed:
. macro __BPF_FEATURE_ARENA_CAST -> __BPF_FEATURE_ADDR_SPACE_CAST
. global variables in __attribute__((address_space(N))) are now
  placed in section named ".addr_space.N" instead of ".arena.N".

Adjust libbpf, bpftool, and selftests to match LLVM.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20240315021834.62988-3-alexei.starovoitov@gmail.com
Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2024-03-12T01:06:04+00:00 Jakub Kicinski kuba@kernel.org 2024-03-12T01:06:04+00:00 5f20e6ab1f65aaaaae248e6946d5cb6d039e7de8 Alexei Starovoitov says: ==================== pull-request: bpf-next 2024-03-11 We've added 59 non-merge commits during the last 9 day(s) which contain a total of 88 files changed, 4181 insertions(+), 590 deletions(-). The main changes are: 1) Enforce VM_IOREMAP flag and range in ioremap_page_range and introduce VM_SPARSE kind and vm_area_[un]map_pages to be used in bpf_arena, from Alexei. 2) Introduce bpf_arena which is sparse shared memory region between bpf program and user space where structures inside the arena can have pointers to other areas of the arena, and pointers work seamlessly for both user-space programs and bpf programs, from Alexei and Andrii. 3) Introduce may_goto instruction that is a contract between the verifier and the program. The verifier allows the program to loop assuming it's behaving well, but reserves the right to terminate it, from Alexei. 4) Use IETF format for field definitions in the BPF standard document, from Dave. 5) Extend struct_ops libbpf APIs to allow specify version suffixes for stuct_ops map types, share the same BPF program between several map definitions, and other improvements, from Eduard. 6) Enable struct_ops support for more than one page in trampolines, from Kui-Feng. 7) Support kCFI + BPF on riscv64, from Puranjay. 8) Use bpf_prog_pack for arm64 bpf trampoline, from Puranjay. 9) Fix roundup_pow_of_two undefined behavior on 32-bit archs, from Toke. ==================== Link: https://lore.kernel.org/r/20240312003646.8692-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Alexei Starovoitov says:

====================
pull-request: bpf-next 2024-03-11

We've added 59 non-merge commits during the last 9 day(s) which contain
a total of 88 files changed, 4181 insertions(+), 590 deletions(-).

The main changes are:

1) Enforce VM_IOREMAP flag and range in ioremap_page_range and introduce
   VM_SPARSE kind and vm_area_[un]map_pages to be used in bpf_arena,
   from Alexei.

2) Introduce bpf_arena which is sparse shared memory region between bpf
   program and user space where structures inside the arena can have
   pointers to other areas of the arena, and pointers work seamlessly for
   both user-space programs and bpf programs, from Alexei and Andrii.

3) Introduce may_goto instruction that is a contract between the verifier
   and the program. The verifier allows the program to loop assuming it's
   behaving well, but reserves the right to terminate it, from Alexei.

4) Use IETF format for field definitions in the BPF standard
   document, from Dave.

5) Extend struct_ops libbpf APIs to allow specify version suffixes for
   stuct_ops map types, share the same BPF program between several map
   definitions, and other improvements, from Eduard.

6) Enable struct_ops support for more than one page in trampolines,
   from Kui-Feng.

7) Support kCFI + BPF on riscv64, from Puranjay.

8) Use bpf_prog_pack for arm64 bpf trampoline, from Puranjay.

9) Fix roundup_pow_of_two undefined behavior on 32-bit archs, from Toke.
====================

Link: https://lore.kernel.org/r/20240312003646.8692-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
selftests/bpf: Add kprobe multi triggering benchmarks 2024-03-11T23:06:48+00:00 Jiri Olsa jolsa@kernel.org 2024-03-11T21:10:23+00:00 379b97bbf02feecae5ce870bc0c67e3d723e30f5 Adding kprobe multi triggering benchmarks. It's useful now to bench new fprobe implementation and might be useful later as well. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240311211023.590321-1-jolsa@kernel.org 
Adding kprobe multi triggering benchmarks. It's useful now to bench
new fprobe implementation and might be useful later as well.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240311211023.590321-1-jolsa@kernel.org
selftests/bpf: Add bpf_arena_htab test. 2024-03-11T22:43:43+00:00 Alexei Starovoitov ast@kernel.org 2024-03-08T01:08:12+00:00 8df839ae23b8c581bdac4b6970d029d65a415852 bpf_arena_htab.h - hash table implemented as bpf program Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240308010812.89848-15-alexei.starovoitov@gmail.com 
bpf_arena_htab.h - hash table implemented as bpf program

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240308010812.89848-15-alexei.starovoitov@gmail.com
selftests/bpf: Add bpf_arena_list test. 2024-03-11T22:43:43+00:00 Alexei Starovoitov ast@kernel.org 2024-03-08T01:08:11+00:00 9f2c156f90a422b4897a8c2831076a96a31413d1 bpf_arena_alloc.h - implements page_frag allocator as a bpf program. bpf_arena_list.h - doubly linked link list as a bpf program. Compiled as a bpf program and as native C code. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240308010812.89848-14-alexei.starovoitov@gmail.com 
bpf_arena_alloc.h - implements page_frag allocator as a bpf program.
bpf_arena_list.h - doubly linked link list as a bpf program.

Compiled as a bpf program and as native C code.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240308010812.89848-14-alexei.starovoitov@gmail.com