#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
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");
SEC("socket")
__description("map in map access")
__success __success_unpriv __retval(0)
__naked void map_in_map_access(void)
{
asm volatile (" \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r2 = r10; \
r2 += -4; \
r1 = %[map_in_map] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r2 = r10; \
r2 += -4; \
r1 = r0; \
call %[bpf_map_lookup_elem]; \
l0_%=: r0 = 0; \
exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_in_map)
: __clobber_all);
}
SEC("xdp")
__description("map in map state pruning")
__success __msg("processed 15 insns")
__log_level(2) __retval(0) __flag(BPF_F_TEST_STATE_FREQ)
__naked void map_in_map_state_pruning(void)
{
asm volatile (" \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r6 = r10; \
r6 += -4; \
r2 = r6; \
r1 = %[map_in_map] ll; \
call %[bpf_map_lookup_elem]; \
if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r2 = r6; \
r1 = r0; \
call %[bpf_map_lookup_elem]; \
if r0 != 0 goto l1_%=; \
r2 = r6; \
r1 = %[map_in_map] ll; \
call %[bpf_map_lookup_elem]; \
if r0 != 0 goto l2_%=; \
exit; \
l2_%=: r2 = r6; \
r1 = r0; \
call %[bpf_map_lookup_elem]; \
if r0 != 0 goto l1_%=; \
exit; \
l1_%=: r0 = *(u32*)(r0 + 0); \
exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_in_map)
: __clobber_all);
}
SEC("socket")
__description("invalid inner map pointer")
__failure __msg("R1 pointer arithmetic on map_ptr prohibited")
__failure_unpriv
__naked void invalid_inner_map_pointer(void)
{
asm volatile (" \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r2 = r10; \
r2 += -4; \
r1 = %[map_in_map] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r2 = r10; \
r2 += -4; \
r1 = r0; \
r1 += 8; \
call %[bpf_map_lookup_elem]; \
l0_%=: r0 = 0; \
exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_in_map)
: __clobber_all);
}
SEC("socket")
__description("forgot null checking on the inner map pointer")
__failure __msg("R1 type=map_value_or_null expected=map_ptr")
__failure_unpriv
__naked void on_the_inner_map_pointer(void)
{
asm volatile (" \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r2 = r10; \
r2 += -4; \
r1 = %[map_in_map] ll; \
call %[bpf_map_lookup_elem]; \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r2 = r10; \
r2 += -4; \
r1 = r0; \
call %[bpf_map_lookup_elem]; \
r0 = 0; \
exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_in_map)
: __clobber_all);
}
SEC("socket")
__description("map_ptr is never null")
__success
__naked void map_ptr_is_never_null(void)
{
asm volatile (" \
r0 = 0; \
r1 = %[map_in_map] ll; \
if r1 != 0 goto l0_%=; \
r10 = 42; \
l0_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_in_map)
: __clobber_all);
}
SEC("socket")
__description("map_ptr is never null inner")
__success
__naked void map_ptr_is_never_null_inner(void)
{
asm volatile (" \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r2 = r10; \
r2 += -4; \
r1 = %[map_in_map] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
if r0 != 0 goto l0_%=; \
r10 = 42; \
l0_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_in_map)
: __clobber_all);
}
SEC("socket")
__description("map_ptr is never null inner spill fill")
__success
__naked void map_ptr_is_never_null_inner_spill_fill(void)
{
asm volatile (" \
r1 = 0; \
*(u32*)(r10 - 4) = r1; \
r2 = r10; \
r2 += -4; \
r1 = %[map_in_map] ll; \
call %[bpf_map_lookup_elem]; \
if r0 != 0 goto l0_%=; \
exit; \
l0_%=: *(u64 *)(r10 -16) = r0; \
r1 = *(u64 *)(r10 -16); \
if r1 == 0 goto l1_%=; \
exit; \
l1_%=: r10 = 42; \
exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_in_map)
: __clobber_all);
}
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_RINGBUF);
__uint(max_entries, 64 * 1024);
});
} rb_in_map SEC(".maps");
struct rb_ctx {
void *rb;
struct bpf_dynptr dptr;
};
static __always_inline struct rb_ctx __rb_event_reserve(__u32 sz)
{
struct rb_ctx rb_ctx = {};
void *rb;
__u32 cpu = bpf_get_smp_processor_id();
__u32 rb_slot = cpu & 1;
rb = bpf_map_lookup_elem(&rb_in_map, &rb_slot);
if (!rb)
return rb_ctx;
rb_ctx.rb = rb;
bpf_ringbuf_reserve_dynptr(rb, sz, 0, &rb_ctx.dptr);
return rb_ctx;
}
static __noinline void __rb_event_submit(struct rb_ctx *ctx)
{
if (!ctx->rb)
return;
bpf_ringbuf_submit_dynptr(&ctx->dptr, 0);
}
SEC("socket")
int map_ptr_is_never_null_rb(void *ctx)
{
struct rb_ctx event_ctx = __rb_event_reserve(256);
__rb_event_submit(&event_ctx);
return 0;
}
char _license[] SEC("license") = "GPL";
