From 147c8f4470eeae14c566984bd81b33334866ce10 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Thu, 27 Jul 2023 18:13:04 -0700 Subject: [PATCH] selftests/bpf: Add unit tests for new sign-extension load insns Add unit tests for new ldsx insns. The test includes sign-extension with a single value or with a value range. If cpuv4 is not supported due to (1) older compiler, e.g., less than clang version 18, or (2) test runner test_progs and test_progs-no_alu32 which tests cpu v2 and v3, or (3) non-x86_64 arch not supporting new insns in jit yet, a dummy program is added with below output: #318/1 verifier_ldsx/cpuv4 is not supported by compiler or jit, use a dummy test:OK #318 verifier_ldsx:OK to indicate the test passed with a dummy test instead of actually testing cpuv4. I am using a dummy prog to avoid changing the verifier testing infrastructure. Once clang 18 is widely available and other architectures support cpuv4, at least for CI run, the dummy program can be removed. Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20230728011304.3719139-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/prog_tests/verifier.c | 2 + tools/testing/selftests/bpf/progs/verifier_ldsx.c | 131 ++++++++++++++++++++++ 2 files changed, 133 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/verifier_ldsx.c diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c index c375e59..6eec6a9 100644 --- a/tools/testing/selftests/bpf/prog_tests/verifier.c +++ b/tools/testing/selftests/bpf/prog_tests/verifier.c @@ -31,6 +31,7 @@ #include "verifier_int_ptr.skel.h" #include "verifier_jeq_infer_not_null.skel.h" #include "verifier_ld_ind.skel.h" +#include "verifier_ldsx.skel.h" #include "verifier_leak_ptr.skel.h" #include "verifier_loops1.skel.h" #include "verifier_lwt.skel.h" @@ -133,6 +134,7 @@ 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_jeq_infer_not_null(void) { RUN(verifier_jeq_infer_not_null); } void test_verifier_ld_ind(void) { RUN(verifier_ld_ind); } +void test_verifier_ldsx(void) { RUN(verifier_ldsx); } void test_verifier_leak_ptr(void) { RUN(verifier_leak_ptr); } void test_verifier_loops1(void) { RUN(verifier_loops1); } void test_verifier_lwt(void) { RUN(verifier_lwt); } diff --git a/tools/testing/selftests/bpf/progs/verifier_ldsx.c b/tools/testing/selftests/bpf/progs/verifier_ldsx.c new file mode 100644 index 0000000..3c3d1bd --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_ldsx.c @@ -0,0 +1,131 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include "bpf_misc.h" + +#if defined(__TARGET_ARCH_x86) && __clang_major__ >= 18 + +SEC("socket") +__description("LDSX, S8") +__success __success_unpriv __retval(-2) +__naked void ldsx_s8(void) +{ + asm volatile (" \ + r1 = 0x3fe; \ + *(u64 *)(r10 - 8) = r1; \ + r0 = *(s8 *)(r10 - 8); \ + exit; \ +" ::: __clobber_all); +} + +SEC("socket") +__description("LDSX, S16") +__success __success_unpriv __retval(-2) +__naked void ldsx_s16(void) +{ + asm volatile (" \ + r1 = 0x3fffe; \ + *(u64 *)(r10 - 8) = r1; \ + r0 = *(s16 *)(r10 - 8); \ + exit; \ +" ::: __clobber_all); +} + +SEC("socket") +__description("LDSX, S32") +__success __success_unpriv __retval(-1) +__naked void ldsx_s32(void) +{ + asm volatile (" \ + r1 = 0xfffffffe; \ + *(u64 *)(r10 - 8) = r1; \ + r0 = *(s32 *)(r10 - 8); \ + r0 >>= 1; \ + exit; \ +" ::: __clobber_all); +} + +SEC("socket") +__description("LDSX, S8 range checking, privileged") +__log_level(2) __success __retval(1) +__msg("R1_w=scalar(smin=-128,smax=127)") +__naked void ldsx_s8_range_priv(void) +{ + asm volatile (" \ + call %[bpf_get_prandom_u32]; \ + *(u64 *)(r10 - 8) = r0; \ + r1 = *(s8 *)(r10 - 8); \ + /* r1 with s8 range */ \ + if r1 s> 0x7f goto l0_%=; \ + if r1 s< -0x80 goto l0_%=; \ + r0 = 1; \ +l1_%=: \ + exit; \ +l0_%=: \ + r0 = 2; \ + goto l1_%=; \ +" : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +SEC("socket") +__description("LDSX, S16 range checking") +__success __success_unpriv __retval(1) +__naked void ldsx_s16_range(void) +{ + asm volatile (" \ + call %[bpf_get_prandom_u32]; \ + *(u64 *)(r10 - 8) = r0; \ + r1 = *(s16 *)(r10 - 8); \ + /* r1 with s16 range */ \ + if r1 s> 0x7fff goto l0_%=; \ + if r1 s< -0x8000 goto l0_%=; \ + r0 = 1; \ +l1_%=: \ + exit; \ +l0_%=: \ + r0 = 2; \ + goto l1_%=; \ +" : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +SEC("socket") +__description("LDSX, S32 range checking") +__success __success_unpriv __retval(1) +__naked void ldsx_s32_range(void) +{ + asm volatile (" \ + call %[bpf_get_prandom_u32]; \ + *(u64 *)(r10 - 8) = r0; \ + r1 = *(s32 *)(r10 - 8); \ + /* r1 with s16 range */ \ + if r1 s> 0x7fffFFFF goto l0_%=; \ + if r1 s< -0x80000000 goto l0_%=; \ + r0 = 1; \ +l1_%=: \ + exit; \ +l0_%=: \ + r0 = 2; \ + goto l1_%=; \ +" : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +#else + +SEC("socket") +__description("cpuv4 is not supported by compiler or jit, use a dummy test") +__success +int dummy_test(void) +{ + return 0; +} + +#endif + +char _license[] SEC("license") = "GPL"; -- 2.7.4