selftests/bpf: verifier/map_ptr_mixing converted to inline assembly

Test verifier/map_ptr_mixing automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Alexei Starovoitov <[e-mail]>

tools/testing/selftests/bpf/prog_tests/verifier.c

···
 #include "verifier_lwt.skel.h"
 #include "verifier_map_in_map.skel.h"
 #include "verifier_map_ptr.skel.h"
+#include "verifier_map_ptr_mixing.skel.h"
 #include "verifier_map_ret_val.skel.h"
 #include "verifier_masking.skel.h"
 #include "verifier_meta_access.skel.h"
···
 void test_verifier_lwt(void)                  { RUN(verifier_lwt); }
 void test_verifier_map_in_map(void)           { RUN(verifier_map_in_map); }
 void test_verifier_map_ptr(void)              { RUN(verifier_map_ptr); }
+void test_verifier_map_ptr_mixing(void)       { RUN(verifier_map_ptr_mixing); }
 void test_verifier_map_ret_val(void)          { RUN(verifier_map_ret_val); }
 void test_verifier_masking(void)              { RUN(verifier_masking); }
 void test_verifier_meta_access(void)          { RUN(verifier_meta_access); }

tools/testing/selftests/bpf/progs/verifier_map_ptr_mixing.c

···
+// SPDX-License-Identifier: GPL-2.0
+/* Converted from tools/testing/selftests/bpf/verifier/map_ptr_mixing.c */
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+#define MAX_ENTRIES 11
+
+struct test_val {
+	unsigned int index;
+	int foo[MAX_ENTRIES];
+};
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__uint(max_entries, 1);
+	__type(key, int);
+	__type(value, struct test_val);
+} map_array_48b SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH);
+	__uint(max_entries, 1);
+	__type(key, long long);
+	__type(value, struct test_val);
+} map_hash_48b SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
+	__uint(max_entries, 1);
+	__type(key, int);
+	__type(value, int);
+	__array(values, struct {
+		__uint(type, BPF_MAP_TYPE_ARRAY);
+		__uint(max_entries, 1);
+		__type(key, int);
+		__type(value, int);
+	});
+} map_in_map SEC(".maps");
+
+void dummy_prog_42_socket(void);
+void dummy_prog_24_socket(void);
+void dummy_prog_loop1_socket(void);
+void dummy_prog_loop2_socket(void);
+
+struct {
+	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+	__uint(max_entries, 4);
+	__uint(key_size, sizeof(int));
+	__array(values, void (void));
+} map_prog1_socket SEC(".maps") = {
+	.values = {
+		[0] = (void *)&dummy_prog_42_socket,
+		[1] = (void *)&dummy_prog_loop1_socket,
+		[2] = (void *)&dummy_prog_24_socket,
+	},
+};
+
+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") = {
+	.values = {
+		[1] = (void *)&dummy_prog_loop2_socket,
+		[2] = (void *)&dummy_prog_24_socket,
+		[7] = (void *)&dummy_prog_42_socket,
+	},
+};
+
+SEC("socket")
+__auxiliary __auxiliary_unpriv
+__naked void dummy_prog_42_socket(void)
+{
+	asm volatile ("r0 = 42; exit;");
+}
+
+SEC("socket")
+__auxiliary __auxiliary_unpriv
+__naked void dummy_prog_24_socket(void)
+{
+	asm volatile ("r0 = 24; exit;");
+}
+
+SEC("socket")
+__auxiliary __auxiliary_unpriv
+__naked void dummy_prog_loop1_socket(void)
+{
+	asm volatile ("			\
+	r3 = 1;				\
+	r2 = %[map_prog1_socket] ll;	\
+	call %[bpf_tail_call];		\
+	r0 = 41;			\
+	exit;				\
+"	:
+	: __imm(bpf_tail_call),
+	  __imm_addr(map_prog1_socket)
+	: __clobber_all);
+}
+
+SEC("socket")
+__auxiliary __auxiliary_unpriv
+__naked void dummy_prog_loop2_socket(void)
+{
+	asm volatile ("			\
+	r3 = 1;				\
+	r2 = %[map_prog2_socket] ll;	\
+	call %[bpf_tail_call];		\
+	r0 = 41;			\
+	exit;				\
+"	:
+	: __imm(bpf_tail_call),
+	  __imm_addr(map_prog2_socket)
+	: __clobber_all);
+}
+
+SEC("tc")
+__description("calls: two calls returning different map pointers for lookup (hash, array)")
+__success __retval(1)
+__naked void pointers_for_lookup_hash_array(void)
+{
+	asm volatile ("					\
+	/* main prog */					\
+	if r1 != 0 goto l0_%=;				\
+	call pointers_for_lookup_hash_array__1;		\
+	goto l1_%=;					\
+l0_%=:	call pointers_for_lookup_hash_array__2;		\
+l1_%=:	r1 = r0;					\
+	r2 = 0;						\
+	*(u64*)(r10 - 8) = r2;				\
+	r2 = r10;					\
+	r2 += -8;					\
+	call %[bpf_map_lookup_elem];			\
+	if r0 == 0 goto l2_%=;				\
+	r1 = %[test_val_foo];				\
+	*(u64*)(r0 + 0) = r1;				\
+	r0 = 1;						\
+l2_%=:	exit;						\
+"	:
+	: __imm(bpf_map_lookup_elem),
+	  __imm_const(test_val_foo, offsetof(struct test_val, foo))
+	: __clobber_all);
+}
+
+static __naked __noinline __attribute__((used))
+void pointers_for_lookup_hash_array__1(void)
+{
+	asm volatile ("					\
+	r0 = %[map_hash_48b] ll;			\
+	exit;						\
+"	:
+	: __imm_addr(map_hash_48b)
+	: __clobber_all);
+}
+
+static __naked __noinline __attribute__((used))
+void pointers_for_lookup_hash_array__2(void)
+{
+	asm volatile ("					\
+	r0 = %[map_array_48b] ll;			\
+	exit;						\
+"	:
+	: __imm_addr(map_array_48b)
+	: __clobber_all);
+}
+
+SEC("tc")
+__description("calls: two calls returning different map pointers for lookup (hash, map in map)")
+__failure __msg("only read from bpf_array is supported")
+__naked void lookup_hash_map_in_map(void)
+{
+	asm volatile ("					\
+	/* main prog */					\
+	if r1 != 0 goto l0_%=;				\
+	call lookup_hash_map_in_map__1;			\
+	goto l1_%=;					\
+l0_%=:	call lookup_hash_map_in_map__2;			\
+l1_%=:	r1 = r0;					\
+	r2 = 0;						\
+	*(u64*)(r10 - 8) = r2;				\
+	r2 = r10;					\
+	r2 += -8;					\
+	call %[bpf_map_lookup_elem];			\
+	if r0 == 0 goto l2_%=;				\
+	r1 = %[test_val_foo];				\
+	*(u64*)(r0 + 0) = r1;				\
+	r0 = 1;						\
+l2_%=:	exit;						\
+"	:
+	: __imm(bpf_map_lookup_elem),
+	  __imm_const(test_val_foo, offsetof(struct test_val, foo))
+	: __clobber_all);
+}
+
+static __naked __noinline __attribute__((used))
+void lookup_hash_map_in_map__1(void)
+{
+	asm volatile ("					\
+	r0 = %[map_array_48b] ll;			\
+	exit;						\
+"	:
+	: __imm_addr(map_array_48b)
+	: __clobber_all);
+}
+
+static __naked __noinline __attribute__((used))
+void lookup_hash_map_in_map__2(void)
+{
+	asm volatile ("					\
+	r0 = %[map_in_map] ll;				\
+	exit;						\
+"	:
+	: __imm_addr(map_in_map)
+	: __clobber_all);
+}
+
+SEC("socket")
+__description("cond: two branches returning different map pointers for lookup (tail, tail)")
+__success __failure_unpriv __msg_unpriv("tail_call abusing map_ptr")
+__retval(42)
+__naked void pointers_for_lookup_tail_tail_1(void)
+{
+	asm volatile ("					\
+	r6 = *(u32*)(r1 + %[__sk_buff_mark]);		\
+	if r6 != 0 goto l0_%=;				\
+	r2 = %[map_prog2_socket] ll;			\
+	goto l1_%=;					\
+l0_%=:	r2 = %[map_prog1_socket] ll;			\
+l1_%=:	r3 = 7;						\
+	call %[bpf_tail_call];				\
+	r0 = 1;						\
+	exit;						\
+"	:
+	: __imm(bpf_tail_call),
+	  __imm_addr(map_prog1_socket),
+	  __imm_addr(map_prog2_socket),
+	  __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
+	: __clobber_all);
+}
+
+SEC("socket")
+__description("cond: two branches returning same map pointers for lookup (tail, tail)")
+__success __success_unpriv __retval(42)
+__naked void pointers_for_lookup_tail_tail_2(void)
+{
+	asm volatile ("					\
+	r6 = *(u32*)(r1 + %[__sk_buff_mark]);		\
+	if r6 == 0 goto l0_%=;				\
+	r2 = %[map_prog2_socket] ll;			\
+	goto l1_%=;					\
+l0_%=:	r2 = %[map_prog2_socket] ll;			\
+l1_%=:	r3 = 7;						\
+	call %[bpf_tail_call];				\
+	r0 = 1;						\
+	exit;						\
+"	:
+	: __imm(bpf_tail_call),
+	  __imm_addr(map_prog2_socket),
+	  __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
+	: __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/verifier/map_ptr_mixing.c

···
-{
-	"calls: two calls returning different map pointers for lookup (hash, array)",
-	.insns = {
-	/* main prog */
-	BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 2),
-	BPF_CALL_REL(11),
-	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
-	BPF_CALL_REL(12),
-	BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
-	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_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
-	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
-	BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, offsetof(struct test_val, foo)),
-	BPF_MOV64_IMM(BPF_REG_0, 1),
-	BPF_EXIT_INSN(),
-	/* subprog 1 */
-	BPF_LD_MAP_FD(BPF_REG_0, 0),
-	BPF_EXIT_INSN(),
-	/* subprog 2 */
-	BPF_LD_MAP_FD(BPF_REG_0, 0),
-	BPF_EXIT_INSN(),
-	},
-	.prog_type = BPF_PROG_TYPE_SCHED_CLS,
-	.fixup_map_hash_48b = { 13 },
-	.fixup_map_array_48b = { 16 },
-	.result = ACCEPT,
-	.retval = 1,
-},
-{
-	"calls: two calls returning different map pointers for lookup (hash, map in map)",
-	.insns = {
-	/* main prog */
-	BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 2),
-	BPF_CALL_REL(11),
-	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
-	BPF_CALL_REL(12),
-	BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
-	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_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
-	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
-	BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, offsetof(struct test_val, foo)),
-	BPF_MOV64_IMM(BPF_REG_0, 1),
-	BPF_EXIT_INSN(),
-	/* subprog 1 */
-	BPF_LD_MAP_FD(BPF_REG_0, 0),
-	BPF_EXIT_INSN(),
-	/* subprog 2 */
-	BPF_LD_MAP_FD(BPF_REG_0, 0),
-	BPF_EXIT_INSN(),
-	},
-	.prog_type = BPF_PROG_TYPE_SCHED_CLS,
-	.fixup_map_in_map = { 16 },
-	.fixup_map_array_48b = { 13 },
-	.result = REJECT,
-	.errstr = "only read from bpf_array is supported",
-},
-{
-	"cond: two branches returning different map pointers for lookup (tail, tail)",
-	.insns = {
-	BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
-		    offsetof(struct __sk_buff, mark)),
-	BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 0, 3),
-	BPF_LD_MAP_FD(BPF_REG_2, 0),
-	BPF_JMP_IMM(BPF_JA, 0, 0, 2),
-	BPF_LD_MAP_FD(BPF_REG_2, 0),
-	BPF_MOV64_IMM(BPF_REG_3, 7),
-	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
-	BPF_MOV64_IMM(BPF_REG_0, 1),
-	BPF_EXIT_INSN(),
-	},
-	.fixup_prog1 = { 5 },
-	.fixup_prog2 = { 2 },
-	.result_unpriv = REJECT,
-	.errstr_unpriv = "tail_call abusing map_ptr",
-	.result = ACCEPT,
-	.retval = 42,
-},
-{
-	"cond: two branches returning same map pointers for lookup (tail, tail)",
-	.insns = {
-	BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
-		    offsetof(struct __sk_buff, mark)),
-	BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 3),
-	BPF_LD_MAP_FD(BPF_REG_2, 0),
-	BPF_JMP_IMM(BPF_JA, 0, 0, 2),
-	BPF_LD_MAP_FD(BPF_REG_2, 0),
-	BPF_MOV64_IMM(BPF_REG_3, 7),
-	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
-	BPF_MOV64_IMM(BPF_REG_0, 1),
-	BPF_EXIT_INSN(),
-	},
-	.fixup_prog2 = { 2, 5 },
-	.result_unpriv = ACCEPT,
-	.result = ACCEPT,
-	.retval = 42,
-},