selftests/bpf: verifier/ctx converted to inline assembly
authorEduard Zingerman <eddyz87@gmail.com>
Fri, 21 Apr 2023 17:42:15 +0000 (20:42 +0300)
committerAlexei Starovoitov <ast@kernel.org>
Fri, 21 Apr 2023 19:18:03 +0000 (12:18 -0700)
Test verifier/ctx automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230421174234.2391278-6-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
tools/testing/selftests/bpf/prog_tests/verifier.c
tools/testing/selftests/bpf/progs/verifier_ctx.c [new file with mode: 0644]
tools/testing/selftests/bpf/verifier/ctx.c [deleted file]

index 3fb22d2..1a1fd3b 100644 (file)
@@ -17,6 +17,7 @@
 #include "verifier_cgroup_skb.skel.h"
 #include "verifier_cgroup_storage.skel.h"
 #include "verifier_const_or.skel.h"
+#include "verifier_ctx.skel.h"
 #include "verifier_ctx_sk_msg.skel.h"
 #include "verifier_direct_stack_access_wraparound.skel.h"
 #include "verifier_div0.skel.h"
@@ -96,6 +97,7 @@ void test_verifier_cgroup_inv_retcode(void)   { RUN(verifier_cgroup_inv_retcode)
 void test_verifier_cgroup_skb(void)           { RUN(verifier_cgroup_skb); }
 void test_verifier_cgroup_storage(void)       { RUN(verifier_cgroup_storage); }
 void test_verifier_const_or(void)             { RUN(verifier_const_or); }
+void test_verifier_ctx(void)                  { RUN(verifier_ctx); }
 void test_verifier_ctx_sk_msg(void)           { RUN(verifier_ctx_sk_msg); }
 void test_verifier_direct_stack_access_wraparound(void) { RUN(verifier_direct_stack_access_wraparound); }
 void test_verifier_div0(void)                 { RUN(verifier_div0); }
diff --git a/tools/testing/selftests/bpf/progs/verifier_ctx.c b/tools/testing/selftests/bpf/progs/verifier_ctx.c
new file mode 100644 (file)
index 0000000..a83809a
--- /dev/null
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Converted from tools/testing/selftests/bpf/verifier/ctx.c */
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+SEC("tc")
+__description("context stores via BPF_ATOMIC")
+__failure __msg("BPF_ATOMIC stores into R1 ctx is not allowed")
+__naked void context_stores_via_bpf_atomic(void)
+{
+       asm volatile ("                                 \
+       r0 = 0;                                         \
+       lock *(u32 *)(r1 + %[__sk_buff_mark]) += w0;    \
+       exit;                                           \
+"      :
+       : __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
+       : __clobber_all);
+}
+
+SEC("tc")
+__description("arithmetic ops make PTR_TO_CTX unusable")
+__failure __msg("dereference of modified ctx ptr")
+__naked void make_ptr_to_ctx_unusable(void)
+{
+       asm volatile ("                                 \
+       r1 += %[__imm_0];                               \
+       r0 = *(u32*)(r1 + %[__sk_buff_mark]);           \
+       exit;                                           \
+"      :
+       : __imm_const(__imm_0,
+                     offsetof(struct __sk_buff, data) - offsetof(struct __sk_buff, mark)),
+         __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
+       : __clobber_all);
+}
+
+SEC("tc")
+__description("pass unmodified ctx pointer to helper")
+__success __retval(0)
+__naked void unmodified_ctx_pointer_to_helper(void)
+{
+       asm volatile ("                                 \
+       r2 = 0;                                         \
+       call %[bpf_csum_update];                        \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_csum_update)
+       : __clobber_all);
+}
+
+SEC("tc")
+__description("pass modified ctx pointer to helper, 1")
+__failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
+__naked void ctx_pointer_to_helper_1(void)
+{
+       asm volatile ("                                 \
+       r1 += -612;                                     \
+       r2 = 0;                                         \
+       call %[bpf_csum_update];                        \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_csum_update)
+       : __clobber_all);
+}
+
+SEC("socket")
+__description("pass modified ctx pointer to helper, 2")
+__failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
+__failure_unpriv __msg_unpriv("negative offset ctx ptr R1 off=-612 disallowed")
+__naked void ctx_pointer_to_helper_2(void)
+{
+       asm volatile ("                                 \
+       r1 += -612;                                     \
+       call %[bpf_get_socket_cookie];                  \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_socket_cookie)
+       : __clobber_all);
+}
+
+SEC("tc")
+__description("pass modified ctx pointer to helper, 3")
+__failure __msg("variable ctx access var_off=(0x0; 0x4)")
+__naked void ctx_pointer_to_helper_3(void)
+{
+       asm volatile ("                                 \
+       r3 = *(u32*)(r1 + 0);                           \
+       r3 &= 4;                                        \
+       r1 += r3;                                       \
+       r2 = 0;                                         \
+       call %[bpf_csum_update];                        \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_csum_update)
+       : __clobber_all);
+}
+
+SEC("cgroup/sendmsg6")
+__description("pass ctx or null check, 1: ctx")
+__success
+__naked void or_null_check_1_ctx(void)
+{
+       asm volatile ("                                 \
+       call %[bpf_get_netns_cookie];                   \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_netns_cookie)
+       : __clobber_all);
+}
+
+SEC("cgroup/sendmsg6")
+__description("pass ctx or null check, 2: null")
+__success
+__naked void or_null_check_2_null(void)
+{
+       asm volatile ("                                 \
+       r1 = 0;                                         \
+       call %[bpf_get_netns_cookie];                   \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_netns_cookie)
+       : __clobber_all);
+}
+
+SEC("cgroup/sendmsg6")
+__description("pass ctx or null check, 3: 1")
+__failure __msg("R1 type=scalar expected=ctx")
+__naked void or_null_check_3_1(void)
+{
+       asm volatile ("                                 \
+       r1 = 1;                                         \
+       call %[bpf_get_netns_cookie];                   \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_netns_cookie)
+       : __clobber_all);
+}
+
+SEC("cgroup/sendmsg6")
+__description("pass ctx or null check, 4: ctx - const")
+__failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
+__naked void null_check_4_ctx_const(void)
+{
+       asm volatile ("                                 \
+       r1 += -612;                                     \
+       call %[bpf_get_netns_cookie];                   \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_netns_cookie)
+       : __clobber_all);
+}
+
+SEC("cgroup/connect4")
+__description("pass ctx or null check, 5: null (connect)")
+__success
+__naked void null_check_5_null_connect(void)
+{
+       asm volatile ("                                 \
+       r1 = 0;                                         \
+       call %[bpf_get_netns_cookie];                   \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_netns_cookie)
+       : __clobber_all);
+}
+
+SEC("cgroup/post_bind4")
+__description("pass ctx or null check, 6: null (bind)")
+__success
+__naked void null_check_6_null_bind(void)
+{
+       asm volatile ("                                 \
+       r1 = 0;                                         \
+       call %[bpf_get_netns_cookie];                   \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_netns_cookie)
+       : __clobber_all);
+}
+
+SEC("cgroup/post_bind4")
+__description("pass ctx or null check, 7: ctx (bind)")
+__success
+__naked void null_check_7_ctx_bind(void)
+{
+       asm volatile ("                                 \
+       call %[bpf_get_socket_cookie];                  \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_socket_cookie)
+       : __clobber_all);
+}
+
+SEC("cgroup/post_bind4")
+__description("pass ctx or null check, 8: null (bind)")
+__failure __msg("R1 type=scalar expected=ctx")
+__naked void null_check_8_null_bind(void)
+{
+       asm volatile ("                                 \
+       r1 = 0;                                         \
+       call %[bpf_get_socket_cookie];                  \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm(bpf_get_socket_cookie)
+       : __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/verifier/ctx.c b/tools/testing/selftests/bpf/verifier/ctx.c
deleted file mode 100644 (file)
index 2fd3161..0000000
+++ /dev/null
@@ -1,186 +0,0 @@
-{
-       "context stores via BPF_ATOMIC",
-       .insns = {
-       BPF_MOV64_IMM(BPF_REG_0, 0),
-       BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_1, BPF_REG_0, offsetof(struct __sk_buff, mark)),
-       BPF_EXIT_INSN(),
-       },
-       .errstr = "BPF_ATOMIC stores into R1 ctx is not allowed",
-       .result = REJECT,
-       .prog_type = BPF_PROG_TYPE_SCHED_CLS,
-},
-{
-       "arithmetic ops make PTR_TO_CTX unusable",
-       .insns = {
-               BPF_ALU64_IMM(BPF_ADD, BPF_REG_1,
-                             offsetof(struct __sk_buff, data) -
-                             offsetof(struct __sk_buff, mark)),
-               BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
-                           offsetof(struct __sk_buff, mark)),
-               BPF_EXIT_INSN(),
-       },
-       .errstr = "dereference of modified ctx ptr",
-       .result = REJECT,
-       .prog_type = BPF_PROG_TYPE_SCHED_CLS,
-},
-{
-       "pass unmodified ctx pointer to helper",
-       .insns = {
-               BPF_MOV64_IMM(BPF_REG_2, 0),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_csum_update),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_SCHED_CLS,
-       .result = ACCEPT,
-},
-{
-       "pass modified ctx pointer to helper, 1",
-       .insns = {
-               BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
-               BPF_MOV64_IMM(BPF_REG_2, 0),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_csum_update),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_SCHED_CLS,
-       .result = REJECT,
-       .errstr = "negative offset ctx ptr R1 off=-612 disallowed",
-},
-{
-       "pass modified ctx pointer to helper, 2",
-       .insns = {
-               BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_socket_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .result_unpriv = REJECT,
-       .result = REJECT,
-       .errstr_unpriv = "negative offset ctx ptr R1 off=-612 disallowed",
-       .errstr = "negative offset ctx ptr R1 off=-612 disallowed",
-},
-{
-       "pass modified ctx pointer to helper, 3",
-       .insns = {
-               BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, 0),
-               BPF_ALU64_IMM(BPF_AND, BPF_REG_3, 4),
-               BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_3),
-               BPF_MOV64_IMM(BPF_REG_2, 0),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_csum_update),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_SCHED_CLS,
-       .result = REJECT,
-       .errstr = "variable ctx access var_off=(0x0; 0x4)",
-},
-{
-       "pass ctx or null check, 1: ctx",
-       .insns = {
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_netns_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
-       .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
-       .result = ACCEPT,
-},
-{
-       "pass ctx or null check, 2: null",
-       .insns = {
-               BPF_MOV64_IMM(BPF_REG_1, 0),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_netns_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
-       .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
-       .result = ACCEPT,
-},
-{
-       "pass ctx or null check, 3: 1",
-       .insns = {
-               BPF_MOV64_IMM(BPF_REG_1, 1),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_netns_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
-       .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
-       .result = REJECT,
-       .errstr = "R1 type=scalar expected=ctx",
-},
-{
-       "pass ctx or null check, 4: ctx - const",
-       .insns = {
-               BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_netns_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
-       .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
-       .result = REJECT,
-       .errstr = "negative offset ctx ptr R1 off=-612 disallowed",
-},
-{
-       "pass ctx or null check, 5: null (connect)",
-       .insns = {
-               BPF_MOV64_IMM(BPF_REG_1, 0),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_netns_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
-       .expected_attach_type = BPF_CGROUP_INET4_CONNECT,
-       .result = ACCEPT,
-},
-{
-       "pass ctx or null check, 6: null (bind)",
-       .insns = {
-               BPF_MOV64_IMM(BPF_REG_1, 0),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_netns_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
-       .expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
-       .result = ACCEPT,
-},
-{
-       "pass ctx or null check, 7: ctx (bind)",
-       .insns = {
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_socket_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
-       .expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
-       .result = ACCEPT,
-},
-{
-       "pass ctx or null check, 8: null (bind)",
-       .insns = {
-               BPF_MOV64_IMM(BPF_REG_1, 0),
-               BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
-                            BPF_FUNC_get_socket_cookie),
-               BPF_MOV64_IMM(BPF_REG_0, 0),
-               BPF_EXIT_INSN(),
-       },
-       .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
-       .expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
-       .result = REJECT,
-       .errstr = "R1 type=scalar expected=ctx",
-},