From: Eduard Zingerman <eddyz87@gmail.com>
To: bpf@vger.kernel.org, ast@kernel.org
Cc: andrii@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev,
kernel-team@fb.com, yhs@fb.com,
Eduard Zingerman <eddyz87@gmail.com>
Subject: [PATCH bpf-next 24/43] selftests/bpf: verifier/int_ptr.c converted to inline assembly
Date: Sat, 25 Mar 2023 04:55:05 +0200 [thread overview]
Message-ID: <20230325025524.144043-25-eddyz87@gmail.com> (raw)
In-Reply-To: <20230325025524.144043-1-eddyz87@gmail.com>
Test verifier/int_ptr.c automatically converted to use inline assembly.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
---
.../selftests/bpf/prog_tests/verifier.c | 2 +
.../selftests/bpf/progs/verifier_int_ptr.c | 157 +++++++++++++++++
.../testing/selftests/bpf/verifier/int_ptr.c | 161 ------------------
3 files changed, 159 insertions(+), 161 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/verifier_int_ptr.c
delete mode 100644 tools/testing/selftests/bpf/verifier/int_ptr.c
diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c
index 2c3745a1fdcb..d9180da30f1b 100644
--- a/tools/testing/selftests/bpf/prog_tests/verifier.c
+++ b/tools/testing/selftests/bpf/prog_tests/verifier.c
@@ -21,6 +21,7 @@
#include "verifier_helper_packet_access.skel.h"
#include "verifier_helper_restricted.skel.h"
#include "verifier_helper_value_access.skel.h"
+#include "verifier_int_ptr.skel.h"
__maybe_unused
static void run_tests_aux(const char *skel_name, skel_elf_bytes_fn elf_bytes_factory)
@@ -64,3 +65,4 @@ void test_verifier_helper_access_var_len(void) { RUN(verifier_helper_access_var_
void test_verifier_helper_packet_access(void) { RUN(verifier_helper_packet_access); }
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); }
diff --git a/tools/testing/selftests/bpf/progs/verifier_int_ptr.c b/tools/testing/selftests/bpf/progs/verifier_int_ptr.c
new file mode 100644
index 000000000000..b054f9c48143
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/verifier_int_ptr.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Converted from tools/testing/selftests/bpf/verifier/int_ptr.c */
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+SEC("cgroup/sysctl")
+__description("ARG_PTR_TO_LONG uninitialized")
+__failure __msg("invalid indirect read from stack R4 off -16+0 size 8")
+__naked void arg_ptr_to_long_uninitialized(void)
+{
+ asm volatile (" \
+ /* bpf_strtoul arg1 (buf) */ \
+ r7 = r10; \
+ r7 += -8; \
+ r0 = 0x00303036; \
+ *(u64*)(r7 + 0) = r0; \
+ r1 = r7; \
+ /* bpf_strtoul arg2 (buf_len) */ \
+ r2 = 4; \
+ /* bpf_strtoul arg3 (flags) */ \
+ r3 = 0; \
+ /* bpf_strtoul arg4 (res) */ \
+ r7 += -8; \
+ r4 = r7; \
+ /* bpf_strtoul() */ \
+ call %[bpf_strtoul]; \
+ r0 = 1; \
+ exit; \
+" :
+ : __imm(bpf_strtoul)
+ : __clobber_all);
+}
+
+SEC("socket")
+__description("ARG_PTR_TO_LONG half-uninitialized")
+/* in privileged mode reads from uninitialized stack locations are permitted */
+__success __failure_unpriv
+__msg_unpriv("invalid indirect read from stack R4 off -16+4 size 8")
+__retval(0)
+__naked void ptr_to_long_half_uninitialized(void)
+{
+ asm volatile (" \
+ /* bpf_strtoul arg1 (buf) */ \
+ r7 = r10; \
+ r7 += -8; \
+ r0 = 0x00303036; \
+ *(u64*)(r7 + 0) = r0; \
+ r1 = r7; \
+ /* bpf_strtoul arg2 (buf_len) */ \
+ r2 = 4; \
+ /* bpf_strtoul arg3 (flags) */ \
+ r3 = 0; \
+ /* bpf_strtoul arg4 (res) */ \
+ r7 += -8; \
+ *(u32*)(r7 + 0) = r0; \
+ r4 = r7; \
+ /* bpf_strtoul() */ \
+ call %[bpf_strtoul]; \
+ r0 = 0; \
+ exit; \
+" :
+ : __imm(bpf_strtoul)
+ : __clobber_all);
+}
+
+SEC("cgroup/sysctl")
+__description("ARG_PTR_TO_LONG misaligned")
+__failure __msg("misaligned stack access off (0x0; 0x0)+-20+0 size 8")
+__naked void arg_ptr_to_long_misaligned(void)
+{
+ asm volatile (" \
+ /* bpf_strtoul arg1 (buf) */ \
+ r7 = r10; \
+ r7 += -8; \
+ r0 = 0x00303036; \
+ *(u64*)(r7 + 0) = r0; \
+ r1 = r7; \
+ /* bpf_strtoul arg2 (buf_len) */ \
+ r2 = 4; \
+ /* bpf_strtoul arg3 (flags) */ \
+ r3 = 0; \
+ /* bpf_strtoul arg4 (res) */ \
+ r7 += -12; \
+ r0 = 0; \
+ *(u32*)(r7 + 0) = r0; \
+ *(u64*)(r7 + 4) = r0; \
+ r4 = r7; \
+ /* bpf_strtoul() */ \
+ call %[bpf_strtoul]; \
+ r0 = 1; \
+ exit; \
+" :
+ : __imm(bpf_strtoul)
+ : __clobber_all);
+}
+
+SEC("cgroup/sysctl")
+__description("ARG_PTR_TO_LONG size < sizeof(long)")
+__failure __msg("invalid indirect access to stack R4 off=-4 size=8")
+__naked void to_long_size_sizeof_long(void)
+{
+ asm volatile (" \
+ /* bpf_strtoul arg1 (buf) */ \
+ r7 = r10; \
+ r7 += -16; \
+ r0 = 0x00303036; \
+ *(u64*)(r7 + 0) = r0; \
+ r1 = r7; \
+ /* bpf_strtoul arg2 (buf_len) */ \
+ r2 = 4; \
+ /* bpf_strtoul arg3 (flags) */ \
+ r3 = 0; \
+ /* bpf_strtoul arg4 (res) */ \
+ r7 += 12; \
+ *(u32*)(r7 + 0) = r0; \
+ r4 = r7; \
+ /* bpf_strtoul() */ \
+ call %[bpf_strtoul]; \
+ r0 = 1; \
+ exit; \
+" :
+ : __imm(bpf_strtoul)
+ : __clobber_all);
+}
+
+SEC("cgroup/sysctl")
+__description("ARG_PTR_TO_LONG initialized")
+__success
+__naked void arg_ptr_to_long_initialized(void)
+{
+ asm volatile (" \
+ /* bpf_strtoul arg1 (buf) */ \
+ r7 = r10; \
+ r7 += -8; \
+ r0 = 0x00303036; \
+ *(u64*)(r7 + 0) = r0; \
+ r1 = r7; \
+ /* bpf_strtoul arg2 (buf_len) */ \
+ r2 = 4; \
+ /* bpf_strtoul arg3 (flags) */ \
+ r3 = 0; \
+ /* bpf_strtoul arg4 (res) */ \
+ r7 += -8; \
+ *(u64*)(r7 + 0) = r0; \
+ r4 = r7; \
+ /* bpf_strtoul() */ \
+ call %[bpf_strtoul]; \
+ r0 = 1; \
+ exit; \
+" :
+ : __imm(bpf_strtoul)
+ : __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/verifier/int_ptr.c b/tools/testing/selftests/bpf/verifier/int_ptr.c
deleted file mode 100644
index 02d9e004260b..000000000000
--- a/tools/testing/selftests/bpf/verifier/int_ptr.c
+++ /dev/null
@@ -1,161 +0,0 @@
-{
- "ARG_PTR_TO_LONG uninitialized",
- .insns = {
- /* bpf_strtoul arg1 (buf) */
- BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
- BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
- BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
-
- BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
-
- /* bpf_strtoul arg2 (buf_len) */
- BPF_MOV64_IMM(BPF_REG_2, 4),
-
- /* bpf_strtoul arg3 (flags) */
- BPF_MOV64_IMM(BPF_REG_3, 0),
-
- /* bpf_strtoul arg4 (res) */
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
- BPF_MOV64_REG(BPF_REG_4, BPF_REG_7),
-
- /* bpf_strtoul() */
- BPF_EMIT_CALL(BPF_FUNC_strtoul),
-
- BPF_MOV64_IMM(BPF_REG_0, 1),
- BPF_EXIT_INSN(),
- },
- .result = REJECT,
- .prog_type = BPF_PROG_TYPE_CGROUP_SYSCTL,
- .errstr = "invalid indirect read from stack R4 off -16+0 size 8",
-},
-{
- "ARG_PTR_TO_LONG half-uninitialized",
- .insns = {
- /* bpf_strtoul arg1 (buf) */
- BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
- BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
- BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
-
- BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
-
- /* bpf_strtoul arg2 (buf_len) */
- BPF_MOV64_IMM(BPF_REG_2, 4),
-
- /* bpf_strtoul arg3 (flags) */
- BPF_MOV64_IMM(BPF_REG_3, 0),
-
- /* bpf_strtoul arg4 (res) */
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
- BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
- BPF_MOV64_REG(BPF_REG_4, BPF_REG_7),
-
- /* bpf_strtoul() */
- BPF_EMIT_CALL(BPF_FUNC_strtoul),
-
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_EXIT_INSN(),
- },
- .result_unpriv = REJECT,
- .errstr_unpriv = "invalid indirect read from stack R4 off -16+4 size 8",
- /* in privileged mode reads from uninitialized stack locations are permitted */
- .result = ACCEPT,
-},
-{
- "ARG_PTR_TO_LONG misaligned",
- .insns = {
- /* bpf_strtoul arg1 (buf) */
- BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
- BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
- BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
-
- BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
-
- /* bpf_strtoul arg2 (buf_len) */
- BPF_MOV64_IMM(BPF_REG_2, 4),
-
- /* bpf_strtoul arg3 (flags) */
- BPF_MOV64_IMM(BPF_REG_3, 0),
-
- /* bpf_strtoul arg4 (res) */
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -12),
- BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
- BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 4),
- BPF_MOV64_REG(BPF_REG_4, BPF_REG_7),
-
- /* bpf_strtoul() */
- BPF_EMIT_CALL(BPF_FUNC_strtoul),
-
- BPF_MOV64_IMM(BPF_REG_0, 1),
- BPF_EXIT_INSN(),
- },
- .result = REJECT,
- .prog_type = BPF_PROG_TYPE_CGROUP_SYSCTL,
- .errstr = "misaligned stack access off (0x0; 0x0)+-20+0 size 8",
-},
-{
- "ARG_PTR_TO_LONG size < sizeof(long)",
- .insns = {
- /* bpf_strtoul arg1 (buf) */
- BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -16),
- BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
- BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
-
- BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
-
- /* bpf_strtoul arg2 (buf_len) */
- BPF_MOV64_IMM(BPF_REG_2, 4),
-
- /* bpf_strtoul arg3 (flags) */
- BPF_MOV64_IMM(BPF_REG_3, 0),
-
- /* bpf_strtoul arg4 (res) */
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, 12),
- BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
- BPF_MOV64_REG(BPF_REG_4, BPF_REG_7),
-
- /* bpf_strtoul() */
- BPF_EMIT_CALL(BPF_FUNC_strtoul),
-
- BPF_MOV64_IMM(BPF_REG_0, 1),
- BPF_EXIT_INSN(),
- },
- .result = REJECT,
- .prog_type = BPF_PROG_TYPE_CGROUP_SYSCTL,
- .errstr = "invalid indirect access to stack R4 off=-4 size=8",
-},
-{
- "ARG_PTR_TO_LONG initialized",
- .insns = {
- /* bpf_strtoul arg1 (buf) */
- BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
- BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
- BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
-
- BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
-
- /* bpf_strtoul arg2 (buf_len) */
- BPF_MOV64_IMM(BPF_REG_2, 4),
-
- /* bpf_strtoul arg3 (flags) */
- BPF_MOV64_IMM(BPF_REG_3, 0),
-
- /* bpf_strtoul arg4 (res) */
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
- BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
- BPF_MOV64_REG(BPF_REG_4, BPF_REG_7),
-
- /* bpf_strtoul() */
- BPF_EMIT_CALL(BPF_FUNC_strtoul),
-
- BPF_MOV64_IMM(BPF_REG_0, 1),
- BPF_EXIT_INSN(),
- },
- .result = ACCEPT,
- .prog_type = BPF_PROG_TYPE_CGROUP_SYSCTL,
-},
--
2.40.0
next prev parent reply other threads:[~2023-03-25 2:56 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-25 2:54 [PATCH bpf-next 00/43] First set of verifier/*.c migrated to inline assembly Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 01/43] selftests/bpf: Report program name on parse_test_spec error Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 02/43] selftests/bpf: __imm_insn & __imm_const macro for bpf_misc.h Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 03/43] selftests/bpf: Unprivileged tests for test_loader.c Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 04/43] selftests/bpf: Tests execution support " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 05/43] selftests/bpf: prog_tests entry point for migrated test_verifier tests Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 06/43] selftests/bpf: verifier/and.c converted to inline assembly Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 07/43] selftests/bpf: verifier/array_access.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 08/43] selftests/bpf: verifier/basic_stack.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 09/43] selftests/bpf: verifier/bounds_deduction.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 10/43] selftests/bpf: verifier/bounds_mix_sign_unsign.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 11/43] selftests/bpf: verifier/cfg.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 12/43] selftests/bpf: verifier/cgroup_inv_retcode.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 13/43] selftests/bpf: verifier/cgroup_skb.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 14/43] selftests/bpf: verifier/cgroup_storage.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 15/43] selftests/bpf: verifier/const_or.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 16/43] selftests/bpf: verifier/ctx_sk_msg.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 17/43] selftests/bpf: verifier/direct_stack_access_wraparound.c " Eduard Zingerman
2023-03-25 2:54 ` [PATCH bpf-next 18/43] selftests/bpf: verifier/div0.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 19/43] selftests/bpf: verifier/div_overflow.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 20/43] selftests/bpf: verifier/helper_access_var_len.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 21/43] selftests/bpf: verifier/helper_packet_access.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 22/43] selftests/bpf: verifier/helper_restricted.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 23/43] selftests/bpf: verifier/helper_value_access.c " Eduard Zingerman
2023-03-25 2:55 ` Eduard Zingerman [this message]
2023-03-25 2:55 ` [PATCH bpf-next 25/43] selftests/bpf: verifier/ld_ind.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 26/43] selftests/bpf: verifier/leak_ptr.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 27/43] selftests/bpf: verifier/map_ptr.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 28/43] selftests/bpf: verifier/map_ret_val.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 29/43] selftests/bpf: verifier/masking.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 30/43] selftests/bpf: verifier/meta_access.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 31/43] selftests/bpf: verifier/raw_stack.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 32/43] selftests/bpf: verifier/raw_tp_writable.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 33/43] selftests/bpf: verifier/ringbuf.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 34/43] selftests/bpf: verifier/spill_fill.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 35/43] selftests/bpf: verifier/stack_ptr.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 36/43] selftests/bpf: verifier/uninit.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 37/43] selftests/bpf: verifier/value_adj_spill.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 38/43] selftests/bpf: verifier/value.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 39/43] selftests/bpf: verifier/value_or_null.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 40/43] selftests/bpf: verifier/var_off.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 41/43] selftests/bpf: verifier/xadd.c " Eduard Zingerman
2023-03-25 2:55 ` [PATCH bpf-next 42/43] selftests/bpf: verifier/xdp.c " Eduard Zingerman
2023-03-25 3:23 ` [PATCH bpf-next 00/43] First set of verifier/*.c migrated " Stanislav Fomichev
2023-03-25 12:20 ` Eduard Zingerman
2023-03-25 16:16 ` Stanislav Fomichev
2023-03-26 1:19 ` Alexei Starovoitov
2023-03-27 3:15 ` Andrii Nakryiko
2023-03-27 3:57 ` Alexei Starovoitov
2023-03-27 11:26 ` Eduard Zingerman
2023-03-27 16:35 ` Andrii Nakryiko
2023-03-27 16:37 ` Andrii Nakryiko
2023-03-26 1:32 ` patchwork-bot+netdevbpf
2023-03-28 3:48 ` Daniel Borkmann
2023-03-28 21:52 ` Eduard Zingerman
2023-03-28 22:24 ` Andrii Nakryiko
2023-03-28 22:38 ` Eduard Zingerman
2023-03-28 23:31 ` Alexei Starovoitov
2023-03-29 0:11 ` Andrii Nakryiko
2023-03-29 0:07 ` Andrii Nakryiko
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