linux/tools/testing/selftests/bpf/progs/verifier_value_illegal_alu.c

// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/value_illegal_alu.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_HASH);
	__uint(max_entries, 1);
	__type(key, long long);
	__type(value, struct test_val);
} map_hash_48b SEC(".maps");

SEC("socket")
__description("map element value illegal alu op, 1")
__failure __msg("R0 bitwise operator &= on pointer")
__failure_unpriv
__naked void value_illegal_alu_op_1(void)
{
	asm volatile ("					\
	r2 = r10;					\
	r2 += -8;					\
	r1 = 0;						\
	*(u64*)(r2 + 0) = r1;				\
	r1 = %[map_hash_48b] ll;			\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	r0 &= 8;					\
	r1 = 22;					\
	*(u64*)(r0 + 0) = r1;				\
l0_%=:	exit;						\
"	:
	: __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_48b)
	: __clobber_all);
}

SEC("socket")
__description("map element value illegal alu op, 2")
__failure __msg("R0 32-bit pointer arithmetic prohibited")
__failure_unpriv
__naked void value_illegal_alu_op_2(void)
{
	asm volatile ("					\
	r2 = r10;					\
	r2 += -8;					\
	r1 = 0;						\
	*(u64*)(r2 + 0) = r1;				\
	r1 = %[map_hash_48b] ll;			\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	w0 += 0;					\
	r1 = 22;					\
	*(u64*)(r0 + 0) = r1;				\
l0_%=:	exit;						\
"	:
	: __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_48b)
	: __clobber_all);
}

SEC("socket")
__description("map element value illegal alu op, 3")
__failure __msg("R0 pointer arithmetic with /= operator")
__failure_unpriv
__naked void value_illegal_alu_op_3(void)
{
	asm volatile ("					\
	r2 = r10;					\
	r2 += -8;					\
	r1 = 0;						\
	*(u64*)(r2 + 0) = r1;				\
	r1 = %[map_hash_48b] ll;			\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	r0 /= 42;					\
	r1 = 22;					\
	*(u64*)(r0 + 0) = r1;				\
l0_%=:	exit;						\
"	:
	: __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_48b)
	: __clobber_all);
}

SEC("socket")
__description("map element value illegal alu op, 4")
__failure __msg("invalid mem access 'scalar'")
__failure_unpriv __msg_unpriv("R0 pointer arithmetic prohibited")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void value_illegal_alu_op_4(void)
{
	asm volatile ("					\
	r2 = r10;					\
	r2 += -8;					\
	r1 = 0;						\
	*(u64*)(r2 + 0) = r1;				\
	r1 = %[map_hash_48b] ll;			\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	r0 = be64 r0;					\
	r1 = 22;					\
	*(u64*)(r0 + 0) = r1;				\
l0_%=:	exit;						\
"	:
	: __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_48b)
	: __clobber_all);
}

SEC("socket")
__description("map element value illegal alu op, 5")
__failure __msg("R0 invalid mem access 'scalar'")
__msg_unpriv("leaking pointer from stack off -8")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void value_illegal_alu_op_5(void)
{
	asm volatile ("					\
	r2 = r10;					\
	r2 += -8;					\
	r1 = 0;						\
	*(u64*)(r2 + 0) = r1;				\
	r1 = %[map_hash_48b] ll;			\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	r3 = 4096;					\
	r2 = r10;					\
	r2 += -8;					\
	*(u64*)(r2 + 0) = r0;				\
	lock *(u64 *)(r2 + 0) += r3;			\
	r0 = *(u64*)(r2 + 0);				\
	r1 = 22;					\
	*(u64*)(r0 + 0) = r1;				\
l0_%=:	exit;						\
"	:
	: __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_48b)
	: __clobber_all);
}

SEC("flow_dissector")
__description("flow_keys illegal alu op with variable offset")
__failure __msg("R7 pointer arithmetic on flow_keys prohibited")
__naked void flow_keys_illegal_variable_offset_alu(void)
{
	asm volatile("					\
	r6 = r1;					\
	r7 = *(u64*)(r6 + %[flow_keys_off]);		\
	r8 = 8;						\
	r8 /= 1;					\
	r8 &= 8;					\
	r7 += r8;					\
	r0 = *(u64*)(r7 + 0);				\
	exit;						\
"	:
	: __imm_const(flow_keys_off, offsetof(struct __sk_buff, flow_keys))
	: __clobber_all);
}

char _license[] SEC("license") = "GPL";