From 583c7ce5be093277ef1691f35d9bec5ef9934e24 Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Sat, 25 Mar 2023 04:55:07 +0200 Subject: [PATCH] selftests/bpf: verifier/leak_ptr.c converted to inline assembly Test verifier/leak_ptr.c automatically converted to use inline assembly. Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20230325025524.144043-27-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov --- .../selftests/bpf/prog_tests/verifier.c | 2 + .../selftests/bpf/progs/verifier_leak_ptr.c | 92 +++++++++++++++++++ .../testing/selftests/bpf/verifier/leak_ptr.c | 67 -------------- 3 files changed, 94 insertions(+), 67 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/verifier_leak_ptr.c delete mode 100644 tools/testing/selftests/bpf/verifier/leak_ptr.c diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c index d8d4464b6112..f8b3b6beba3f 100644 --- a/tools/testing/selftests/bpf/prog_tests/verifier.c +++ b/tools/testing/selftests/bpf/prog_tests/verifier.c @@ -23,6 +23,7 @@ #include "verifier_helper_value_access.skel.h" #include "verifier_int_ptr.skel.h" #include "verifier_ld_ind.skel.h" +#include "verifier_leak_ptr.skel.h" __maybe_unused static void run_tests_aux(const char *skel_name, skel_elf_bytes_fn elf_bytes_factory) @@ -68,3 +69,4 @@ void test_verifier_helper_restricted(void) { RUN(verifier_helper_restricted); void test_verifier_helper_value_access(void) { RUN(verifier_helper_value_access); } void test_verifier_int_ptr(void) { RUN(verifier_int_ptr); } void test_verifier_ld_ind(void) { RUN(verifier_ld_ind); } +void test_verifier_leak_ptr(void) { RUN(verifier_leak_ptr); } diff --git a/tools/testing/selftests/bpf/progs/verifier_leak_ptr.c b/tools/testing/selftests/bpf/progs/verifier_leak_ptr.c new file mode 100644 index 000000000000..d153fbe50055 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_leak_ptr.c @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Converted from tools/testing/selftests/bpf/verifier/leak_ptr.c */ + +#include +#include +#include "bpf_misc.h" + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 1); + __type(key, long long); + __type(value, long long); +} map_hash_8b SEC(".maps"); + +SEC("socket") +__description("leak pointer into ctx 1") +__failure __msg("BPF_ATOMIC stores into R1 ctx is not allowed") +__failure_unpriv __msg_unpriv("R2 leaks addr into mem") +__naked void leak_pointer_into_ctx_1(void) +{ + asm volatile (" \ + r0 = 0; \ + *(u64*)(r1 + %[__sk_buff_cb_0]) = r0; \ + r2 = %[map_hash_8b] ll; \ + lock *(u64 *)(r1 + %[__sk_buff_cb_0]) += r2; \ + exit; \ +" : + : __imm_addr(map_hash_8b), + __imm_const(__sk_buff_cb_0, offsetof(struct __sk_buff, cb[0])) + : __clobber_all); +} + +SEC("socket") +__description("leak pointer into ctx 2") +__failure __msg("BPF_ATOMIC stores into R1 ctx is not allowed") +__failure_unpriv __msg_unpriv("R10 leaks addr into mem") +__naked void leak_pointer_into_ctx_2(void) +{ + asm volatile (" \ + r0 = 0; \ + *(u64*)(r1 + %[__sk_buff_cb_0]) = r0; \ + lock *(u64 *)(r1 + %[__sk_buff_cb_0]) += r10; \ + exit; \ +" : + : __imm_const(__sk_buff_cb_0, offsetof(struct __sk_buff, cb[0])) + : __clobber_all); +} + +SEC("socket") +__description("leak pointer into ctx 3") +__success __failure_unpriv __msg_unpriv("R2 leaks addr into ctx") +__retval(0) +__naked void leak_pointer_into_ctx_3(void) +{ + asm volatile (" \ + r0 = 0; \ + r2 = %[map_hash_8b] ll; \ + *(u64*)(r1 + %[__sk_buff_cb_0]) = r2; \ + exit; \ +" : + : __imm_addr(map_hash_8b), + __imm_const(__sk_buff_cb_0, offsetof(struct __sk_buff, cb[0])) + : __clobber_all); +} + +SEC("socket") +__description("leak pointer into map val") +__success __failure_unpriv __msg_unpriv("R6 leaks addr into mem") +__retval(0) +__naked void leak_pointer_into_map_val(void) +{ + asm volatile (" \ + r6 = r1; \ + r1 = 0; \ + *(u64*)(r10 - 8) = r1; \ + r2 = r10; \ + r2 += -8; \ + r1 = %[map_hash_8b] ll; \ + call %[bpf_map_lookup_elem]; \ + if r0 == 0 goto l0_%=; \ + r3 = 0; \ + *(u64*)(r0 + 0) = r3; \ + lock *(u64 *)(r0 + 0) += r6; \ +l0_%=: r0 = 0; \ + exit; \ +" : + : __imm(bpf_map_lookup_elem), + __imm_addr(map_hash_8b) + : __clobber_all); +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/verifier/leak_ptr.c b/tools/testing/selftests/bpf/verifier/leak_ptr.c deleted file mode 100644 index 73f0dea95546..000000000000 --- a/tools/testing/selftests/bpf/verifier/leak_ptr.c +++ /dev/null @@ -1,67 +0,0 @@ -{ - "leak pointer into ctx 1", - .insns = { - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, - offsetof(struct __sk_buff, cb[0])), - BPF_LD_MAP_FD(BPF_REG_2, 0), - BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_1, BPF_REG_2, - offsetof(struct __sk_buff, cb[0])), - BPF_EXIT_INSN(), - }, - .fixup_map_hash_8b = { 2 }, - .errstr_unpriv = "R2 leaks addr into mem", - .result_unpriv = REJECT, - .result = REJECT, - .errstr = "BPF_ATOMIC stores into R1 ctx is not allowed", -}, -{ - "leak pointer into ctx 2", - .insns = { - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, - offsetof(struct __sk_buff, cb[0])), - BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_1, BPF_REG_10, - offsetof(struct __sk_buff, cb[0])), - BPF_EXIT_INSN(), - }, - .errstr_unpriv = "R10 leaks addr into mem", - .result_unpriv = REJECT, - .result = REJECT, - .errstr = "BPF_ATOMIC stores into R1 ctx is not allowed", -}, -{ - "leak pointer into ctx 3", - .insns = { - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_LD_MAP_FD(BPF_REG_2, 0), - BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, - offsetof(struct __sk_buff, cb[0])), - BPF_EXIT_INSN(), - }, - .fixup_map_hash_8b = { 1 }, - .errstr_unpriv = "R2 leaks addr into ctx", - .result_unpriv = REJECT, - .result = ACCEPT, -}, -{ - "leak pointer into map val", - .insns = { - BPF_MOV64_REG(BPF_REG_6, BPF_REG_1), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), - BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), - BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), - BPF_LD_MAP_FD(BPF_REG_1, 0), - BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3), - BPF_MOV64_IMM(BPF_REG_3, 0), - BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_3, 0), - BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_6, 0), - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_EXIT_INSN(), - }, - .fixup_map_hash_8b = { 4 }, - .errstr_unpriv = "R6 leaks addr into mem", - .result_unpriv = REJECT, - .result = ACCEPT, -}, -- 2.25.1