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

Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/verifier_value_illegal_alu.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/progs/verifier_value_illegal_alu.c
Extension
.c
Size
5535 bytes
Lines
217
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

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)

Annotation

Implementation Notes