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

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

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/progs/verifier_regalloc.c
Extension
.c
Size
8590 bytes
Lines
365
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("tracepoint")
__description("regalloc basic")
__success __flag(BPF_F_ANY_ALIGNMENT)
__naked void regalloc_basic(void)
{
	asm volatile ("					\
	r6 = r1;					\
	r1 = 0;						\
	*(u64*)(r10 - 8) = r1;				\
	r2 = r10;					\
	r2 += -8;					\
	r1 = %[map_hash_48b] ll;			\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	r7 = r0;					\
	call %[bpf_get_prandom_u32];			\
	r2 = r0;					\
	if r0 s> 20 goto l0_%=;				\
	if r2 s< 0 goto l0_%=;				\
	r7 += r0;					\
	r7 += r2;					\
	r0 = *(u64*)(r7 + 0);				\
l0_%=:	exit;						\
"	:
	: __imm(bpf_get_prandom_u32),
	  __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_48b)
	: __clobber_all);
}

SEC("tracepoint")
__description("regalloc negative")
__failure __msg("invalid access to map value, value_size=48 off=48 size=1")
__naked void regalloc_negative(void)
{
	asm volatile ("					\
	r6 = r1;					\
	r1 = 0;						\
	*(u64*)(r10 - 8) = r1;				\
	r2 = r10;					\
	r2 += -8;					\
	r1 = %[map_hash_48b] ll;			\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	r7 = r0;					\
	call %[bpf_get_prandom_u32];			\
	r2 = r0;					\
	if r0 s> 24 goto l0_%=;				\
	if r2 s< 0 goto l0_%=;				\
	r7 += r0;					\
	r7 += r2;					\
	r0 = *(u8*)(r7 + 0);				\
l0_%=:	exit;						\
"	:
	: __imm(bpf_get_prandom_u32),
	  __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_48b)
	: __clobber_all);
}

SEC("tracepoint")
__description("regalloc src_reg mark")
__success __flag(BPF_F_ANY_ALIGNMENT)
__naked void regalloc_src_reg_mark(void)
{
	asm volatile ("					\
	r6 = r1;					\
	r1 = 0;						\
	*(u64*)(r10 - 8) = r1;				\
	r2 = r10;					\
	r2 += -8;					\
	r1 = %[map_hash_48b] ll;			\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	r7 = r0;					\
	call %[bpf_get_prandom_u32];			\
	r2 = r0;					\
	if r0 s> 20 goto l0_%=;				\

Annotation

Implementation Notes