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|
// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/regalloc.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("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_%=; \
r3 = 0; \
if r3 s>= r2 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 src_reg negative")
__failure __msg("invalid access to map value, value_size=48 off=44 size=8")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void regalloc_src_reg_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> 22 goto l0_%=; \
r3 = 0; \
if r3 s>= r2 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 and spill")
__success __flag(BPF_F_ANY_ALIGNMENT)
__naked void regalloc_and_spill(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_%=; \
/* r0 has upper bound that should propagate into r2 */\
*(u64*)(r10 - 8) = r2; /* spill r2 */ \
r0 = 0; \
r2 = 0; /* clear r0 and r2 */\
r3 = *(u64*)(r10 - 8); /* fill r3 */ \
if r0 s>= r3 goto l0_%=; \
/* r3 has lower and upper bounds */ \
r7 += r3; \
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 and spill negative")
__failure __msg("invalid access to map value, value_size=48 off=48 size=8")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void regalloc_and_spill_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> 48 goto l0_%=; \
/* r0 has upper bound that should propagate into r2 */\
*(u64*)(r10 - 8) = r2; /* spill r2 */ \
r0 = 0; \
r2 = 0; /* clear r0 and r2 */\
r3 = *(u64*)(r10 - 8); /* fill r3 */\
if r0 s>= r3 goto l0_%=; \
/* r3 has lower and upper bounds */ \
r7 += r3; \
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 three regs")
__success __flag(BPF_F_ANY_ALIGNMENT)
__naked void regalloc_three_regs(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; \
r4 = r2; \
if r0 s> 12 goto l0_%=; \
if r2 s< 0 goto l0_%=; \
r7 += r0; \
r7 += r2; \
r7 += r4; \
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 after call")
__success __flag(BPF_F_ANY_ALIGNMENT)
__naked void regalloc_after_call(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]; \
r8 = r0; \
r9 = r0; \
call regalloc_after_call__1; \
if r8 s> 20 goto l0_%=; \
if r9 s< 0 goto l0_%=; \
r7 += r8; \
r7 += r9; \
r0 = *(u64*)(r7 + 0); \
l0_%=: exit; \
" :
: __imm(bpf_get_prandom_u32),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b)
: __clobber_all);
}
static __naked __noinline __attribute__((used))
void regalloc_after_call__1(void)
{
asm volatile (" \
r0 = 0; \
exit; \
" ::: __clobber_all);
}
SEC("tracepoint")
__description("regalloc in callee")
__success __flag(BPF_F_ANY_ALIGNMENT)
__naked void regalloc_in_callee(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]; \
r1 = r0; \
r2 = r0; \
r3 = r7; \
call regalloc_in_callee__1; \
l0_%=: exit; \
" :
: __imm(bpf_get_prandom_u32),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b)
: __clobber_all);
}
static __naked __noinline __attribute__((used))
void regalloc_in_callee__1(void)
{
asm volatile (" \
if r1 s> 20 goto l0_%=; \
if r2 s< 0 goto l0_%=; \
r3 += r1; \
r3 += r2; \
r0 = *(u64*)(r3 + 0); \
exit; \
l0_%=: r0 = 0; \
exit; \
" ::: __clobber_all);
}
SEC("tracepoint")
__description("regalloc, spill, JEQ")
__success
__naked void regalloc_spill_jeq(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]; \
*(u64*)(r10 - 8) = r0; /* spill r0 */ \
if r0 == 0 goto l0_%=; \
l0_%=: /* The verifier will walk the rest twice with r0 == 0 and r0 == map_value */\
call %[bpf_get_prandom_u32]; \
r2 = r0; \
if r2 == 20 goto l1_%=; \
l1_%=: /* The verifier will walk the rest two more times with r0 == 20 and r0 == unknown */\
r3 = *(u64*)(r10 - 8); /* fill r3 with map_value */\
if r3 == 0 goto l2_%=; /* skip ldx if map_value == NULL */\
/* Buggy verifier will think that r3 == 20 here */\
r0 = *(u64*)(r3 + 0); /* read from map_value */\
l2_%=: exit; \
" :
: __imm(bpf_get_prandom_u32),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b)
: __clobber_all);
}
char _license[] SEC("license") = "GPL";
|
