wireguard-linux/tools/testing/selftests/bpf, branch jd/shorter-socket-lock

selftests/bpf: Fix a couple of broken test_btf cases

2020-04-25T00:47:40Z

Commit 51c39bb1d5d1 ("bpf: Introduce function-by-function verification") introduced function linkage flag and changed the error message from "vlen != 0" to "Invalid func linkage" and broke some fake BPF programs. Adjust the test accordingly. AFACT, the programs don't really need any arguments and only look at BTF for maps, so let's drop the args altogether. Before: BTF raw test[103] (func (Non zero vlen)): do_test_raw:3703:FAIL expected err_str:vlen != 0 magic: 0xeb9f version: 1 flags: 0x0 hdr_len: 24 type_off: 0 type_len: 72 str_off: 72 str_len: 10 btf_total_size: 106 [1] INT (anon) size=4 bits_offset=0 nr_bits=32 encoding=SIGNED [2] INT (anon) size=4 bits_offset=0 nr_bits=32 encoding=(none) [3] FUNC_PROTO (anon) return=0 args=(1 a, 2 b) [4] FUNC func type_id=3 Invalid func linkage BTF libbpf test[1] (test_btf_haskv.o): libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: Validating test_long_fname_2() func#1... Arg#0 type PTR in test_long_fname_2() is not supported yet. processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 libbpf: -- END LOG -- libbpf: failed to load program 'dummy_tracepoint' libbpf: failed to load object 'test_btf_haskv.o' do_test_file:4201:FAIL bpf_object__load: -4007 BTF libbpf test[2] (test_btf_newkv.o): libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: Validating test_long_fname_2() func#1... Arg#0 type PTR in test_long_fname_2() is not supported yet. processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 libbpf: -- END LOG -- libbpf: failed to load program 'dummy_tracepoint' libbpf: failed to load object 'test_btf_newkv.o' do_test_file:4201:FAIL bpf_object__load: -4007 BTF libbpf test[3] (test_btf_nokv.o): libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: Validating test_long_fname_2() func#1... Arg#0 type PTR in test_long_fname_2() is not supported yet. processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 libbpf: -- END LOG -- libbpf: failed to load program 'dummy_tracepoint' libbpf: failed to load object 'test_btf_nokv.o' do_test_file:4201:FAIL bpf_object__load: -4007 Fixes: 51c39bb1d5d1 ("bpf: Introduce function-by-function verification") Signed-off-by: Stanislav Fomichev Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200422003753.124921-1-sdf@google.com

selftests/bpf: Add test for freplace program with expected_attach_type

2020-04-25T00:34:30Z

This adds a new selftest that tests the ability to attach an freplace program to a program type that relies on the expected_attach_type of the target program to pass verification. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/158773526831.293902.16011743438619684815.stgit@toke.dk

bpf, selftests: Add test for BPF_STX BPF_B storing R10

2020-04-21T02:25:30Z

This patch adds a test to test_verifier that writes the lower 8 bits of R10 (aka FP) using BPF_B to an array map and reads the result back. The expected behavior is that the result should be the same as first copying R10 to R9, and then storing / loading the lower 8 bits of R9. This test catches a bug that was present in the x86-64 JIT that caused an incorrect encoding for BPF_STX BPF_B when the source operand is R10. Signed-off-by: Xi Wang Signed-off-by: Luke Nelson Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200418232655.23870-2-luke.r.nels@gmail.com

bpf: Forbid XADD on spilled pointers for unprivileged users

2020-04-21T01:41:34Z

When check_xadd() verifies an XADD operation on a pointer to a stack slot containing a spilled pointer, check_stack_read() verifies that the read, which is part of XADD, is valid. However, since the placeholder value -1 is passed as `value_regno`, check_stack_read() can only return a binary decision and can't return the type of the value that was read. The intent here is to verify whether the value read from the stack slot may be used as a SCALAR_VALUE; but since check_stack_read() doesn't check the type, and the type information is lost when check_stack_read() returns, this is not enforced, and a malicious user can abuse XADD to leak spilled kernel pointers. Fix it by letting check_stack_read() verify that the value is usable as a SCALAR_VALUE if no type information is passed to the caller. To be able to use __is_pointer_value() in check_stack_read(), move it up. Fix up the expected unprivileged error message for a BPF selftest that, until now, assumed that unprivileged users can use XADD on stack-spilled pointers. This also gives us a test for the behavior introduced in this patch for free. In theory, this could also be fixed by forbidding XADD on stack spills entirely, since XADD is a locked operation (for operations on memory with concurrency) and there can't be any concurrency on the BPF stack; but Alexei has said that he wants to keep XADD on stack slots working to avoid changes to the test suite [1]. The following BPF program demonstrates how to leak a BPF map pointer as an unprivileged user using this bug: // r7 = map_pointer BPF_LD_MAP_FD(BPF_REG_7, small_map), // r8 = launder(map_pointer) BPF_STX_MEM(BPF_DW, BPF_REG_FP, BPF_REG_7, -8), BPF_MOV64_IMM(BPF_REG_1, 0), ((struct bpf_insn) { .code = BPF_STX | BPF_DW | BPF_XADD, .dst_reg = BPF_REG_FP, .src_reg = BPF_REG_1, .off = -8 }), BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_FP, -8), // store r8 into map BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_7), BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_FP), BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG2, -4), BPF_ST_MEM(BPF_W, BPF_REG_ARG2, 0, 0), BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1), BPF_EXIT_INSN(), BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_8, 0), BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN() [1] https://lore.kernel.org/bpf/20200416211116.qxqcza5vo2ddnkdq@ast-mbp.dhcp.thefacebook.com/ Fixes: 17a5267067f3 ("bpf: verifier (add verifier core)") Signed-off-by: Jann Horn Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200417000007.10734-1-jannh@google.com

selftests/bpf: Check for correct program attach/detach in xdp_attach test

2020-04-15T11:26:08Z

David Ahern noticed that there was a bug in the EXPECTED_FD code so programs did not get detached properly when that parameter was supplied. This case was not included in the xdp_attach tests; so let's add it to be sure that such a bug does not sneak back in down. Fixes: 87854a0b57b3 ("selftests/bpf: Add tests for attaching XDP programs") Reported-by: David Ahern Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200414145025.182163-2-toke@redhat.com

libbpf: Always specify expected_attach_type on program load if supported

2020-04-15T11:22:43Z

For some types of BPF programs that utilize expected_attach_type, libbpf won't set load_attr.expected_attach_type, even if expected_attach_type is known from section definition. This was done to preserve backwards compatibility with old kernels that didn't recognize expected_attach_type attribute yet (which was added in 5e43f899b03a ("bpf: Check attach type at prog load time"). But this is problematic for some BPF programs that utilize newer features that require kernel to know specific expected_attach_type (e.g., extended set of return codes for cgroup_skb/egress programs). This patch makes libbpf specify expected_attach_type by default, but also detect support for this field in kernel and not set it during program load. This allows to have a good metadata for bpf_program (e.g., bpf_program__get_extected_attach_type()), but still work with old kernels (for cases where it can work at all). Additionally, due to expected_attach_type being always set for recognized program types, bpf_program__attach_cgroup doesn't have to do extra checks to determine correct attach type, so remove that additional logic. Also adjust section_names selftest to account for this change. More detailed discussion can be found in [0]. [0] https://lore.kernel.org/bpf/20200412003604.GA15986@rdna-mbp.dhcp.thefacebook.com/ Fixes: 5cf1e9145630 ("bpf: cgroup inet skb programs can return 0 to 3") Fixes: 5e43f899b03a ("bpf: Check attach type at prog load time") Reported-by: Andrey Ignatov Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Song Liu Acked-by: Andrey Ignatov Link: https://lore.kernel.org/bpf/20200414182645.1368174-1-andriin@fb.com

selftests/bpf: Validate frozen map contents stays frozen

2020-04-14T19:28:57Z

Test that frozen and mmap()'ed BPF map can't be mprotect()'ed as writable or executable memory. Also validate that "downgrading" from writable to read-only doesn't screw up internal writable count accounting for the purposes of map freezing. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200410202613.3679837-2-andriin@fb.com

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

2020-04-10T00:39:22Z

Daniel Borkmann says: ==================== pull-request: bpf 2020-04-10 The following pull-request contains BPF updates for your *net* tree. We've added 13 non-merge commits during the last 7 day(s) which contain a total of 13 files changed, 137 insertions(+), 43 deletions(-). The main changes are: 1) JIT code emission fixes for riscv and arm32, from Luke Nelson and Xi Wang. 2) Disable vmlinux BTF info if GCC_PLUGIN_RANDSTRUCT is used, from Slava Bacherikov. 3) Fix oob write in AF_XDP when meta data is used, from Li RongQing. 4) Fix bpf_get_link_xdp_id() handling on single prog when flags are specified, from Andrey Ignatov. 5) Fix sk_assign() BPF helper for request sockets that can have sk_reuseport field uninitialized, from Joe Stringer. 6) Fix mprotect() test case for the BPF LSM, from KP Singh. ==================== Signed-off-by: David S. Miller

selftests/bpf: Add test for bpf_get_link_xdp_id

2020-04-07T23:35:24Z

Add xdp_info selftest that makes sure that bpf_get_link_xdp_id returns valid prog_id for different input modes: * w/ and w/o flags when no program is attached; * w/ and w/o flags when one program is attached. Signed-off-by: Andrey Ignatov Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/2a9a6d1ce33b91ccc1aa3de6dba2d309f2062811.1586236080.git.rdna@fb.com

Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

2020-04-03T20:12:26Z

Pull SPDX updates from Greg KH: "Here are three SPDX patches for 5.7-rc1. One fixes up the SPDX tag for a single driver, while the other two go through the tree and add SPDX tags for all of the .gitignore files as needed. Nothing too complex, but you will get a merge conflict with your current tree, that should be trivial to handle (one file modified by two things, one file deleted.) All three of these have been in linux-next for a while, with no reported issues other than the merge conflict" * tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: ASoC: MT6660: make spdxcheck.py happy .gitignore: add SPDX License Identifier .gitignore: remove too obvious comments