Test verifier/prevent_map_lookup automatically converted to use inline assembly. This was a part of a series [1] but could not be applied becuase another patch from a series had to be witheld. [1] https://lore.kernel.org/bpf/20230421174234.2391278-1-eddyz87@xxxxxxxxx/ Signed-off-by: Eduard Zingerman <eddyz87@xxxxxxxxx> --- .../selftests/bpf/prog_tests/verifier.c | 2 + .../bpf/progs/verifier_prevent_map_lookup.c | 61 +++++++++++++++++++ .../bpf/verifier/prevent_map_lookup.c | 29 --------- 3 files changed, 63 insertions(+), 29 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/verifier_prevent_map_lookup.c delete mode 100644 tools/testing/selftests/bpf/verifier/prevent_map_lookup.c diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c index c8bab8b1a6a4..2497716ee379 100644 --- a/tools/testing/selftests/bpf/prog_tests/verifier.c +++ b/tools/testing/selftests/bpf/prog_tests/verifier.c @@ -42,6 +42,7 @@ #include "verifier_meta_access.skel.h" #include "verifier_netfilter_ctx.skel.h" #include "verifier_netfilter_retcode.skel.h" +#include "verifier_prevent_map_lookup.skel.h" #include "verifier_raw_stack.skel.h" #include "verifier_raw_tp_writable.skel.h" #include "verifier_reg_equal.skel.h" @@ -140,6 +141,7 @@ void test_verifier_masking(void) { RUN(verifier_masking); } void test_verifier_meta_access(void) { RUN(verifier_meta_access); } void test_verifier_netfilter_ctx(void) { RUN(verifier_netfilter_ctx); } void test_verifier_netfilter_retcode(void) { RUN(verifier_netfilter_retcode); } +void test_verifier_prevent_map_lookup(void) { RUN(verifier_prevent_map_lookup); } void test_verifier_raw_stack(void) { RUN(verifier_raw_stack); } void test_verifier_raw_tp_writable(void) { RUN(verifier_raw_tp_writable); } void test_verifier_reg_equal(void) { RUN(verifier_reg_equal); } diff --git a/tools/testing/selftests/bpf/progs/verifier_prevent_map_lookup.c b/tools/testing/selftests/bpf/progs/verifier_prevent_map_lookup.c new file mode 100644 index 000000000000..8d27c780996f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_prevent_map_lookup.c @@ -0,0 +1,61 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Converted from tools/testing/selftests/bpf/verifier/prevent_map_lookup.c */ + +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +struct { + __uint(type, BPF_MAP_TYPE_STACK_TRACE); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} map_stacktrace SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); + __uint(max_entries, 8); + __uint(key_size, sizeof(int)); + __array(values, void (void)); +} map_prog2_socket SEC(".maps"); + +SEC("perf_event") +__description("prevent map lookup in stack trace") +__failure __msg("cannot pass map_type 7 into func bpf_map_lookup_elem") +__naked void map_lookup_in_stack_trace(void) +{ + asm volatile (" \ + r1 = 0; \ + *(u64*)(r10 - 8) = r1; \ + r2 = r10; \ + r2 += -8; \ + r1 = %[map_stacktrace] ll; \ + call %[bpf_map_lookup_elem]; \ + exit; \ +" : + : __imm(bpf_map_lookup_elem), + __imm_addr(map_stacktrace) + : __clobber_all); +} + +SEC("socket") +__description("prevent map lookup in prog array") +__failure __msg("cannot pass map_type 3 into func bpf_map_lookup_elem") +__failure_unpriv +__naked void map_lookup_in_prog_array(void) +{ + asm volatile (" \ + r1 = 0; \ + *(u64*)(r10 - 8) = r1; \ + r2 = r10; \ + r2 += -8; \ + r1 = %[map_prog2_socket] ll; \ + call %[bpf_map_lookup_elem]; \ + exit; \ +" : + : __imm(bpf_map_lookup_elem), + __imm_addr(map_prog2_socket) + : __clobber_all); +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/verifier/prevent_map_lookup.c b/tools/testing/selftests/bpf/verifier/prevent_map_lookup.c deleted file mode 100644 index fc4e301260f6..000000000000 --- a/tools/testing/selftests/bpf/verifier/prevent_map_lookup.c +++ /dev/null @@ -1,29 +0,0 @@ -{ - "prevent map lookup in stack trace", - .insns = { - 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_EXIT_INSN(), - }, - .fixup_map_stacktrace = { 3 }, - .result = REJECT, - .errstr = "cannot pass map_type 7 into func bpf_map_lookup_elem", - .prog_type = BPF_PROG_TYPE_PERF_EVENT, -}, -{ - "prevent map lookup in prog array", - .insns = { - 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_EXIT_INSN(), - }, - .fixup_prog2 = { 3 }, - .result = REJECT, - .errstr = "cannot pass map_type 3 into func bpf_map_lookup_elem", -}, -- 2.40.0
