// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/search_pruning.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");
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1);
__type(key, long long);
__type(value, long long);
} map_hash_8b SEC(".maps");
SEC("socket")
__description("pointer/scalar confusion in state equality check (way 1)")
__success __failure_unpriv __msg_unpriv("R0 leaks addr as return value")
__retval(POINTER_VALUE)
__naked void state_equality_check_way_1(void)
{
asm volatile (" \
r1 = 0; \
*(u64*)(r10 - 8) = r1; \
r2 = r10; \
r2 += -8; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
r0 = *(u64*)(r0 + 0); \
goto l1_%=; \
l0_%=: r0 = r10; \
l1_%=: goto l2_%=; \
l2_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("socket")
__description("pointer/scalar confusion in state equality check (way 2)")
__success __failure_unpriv __msg_unpriv("R0 leaks addr as return value")
__retval(POINTER_VALUE)
__naked void state_equality_check_way_2(void)
{
asm volatile (" \
r1 = 0; \
*(u64*)(r10 - 8) = r1; \
r2 = r10; \
r2 += -8; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 != 0 goto l0_%=; \
r0 = r10; \
goto l1_%=; \
l0_%=: r0 = *(u64*)(r0 + 0); \
l1_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("lwt_in")
__description("liveness pruning and write screening")
__failure __msg("R0 !read_ok")
__naked void liveness_pruning_and_write_screening(void)
{
asm volatile (" \
/* Get an unknown value */ \
r2 = *(u32*)(r1 + 0); \
/* branch conditions teach us nothing about R2 */\
if r2 >= 0 goto l0_%=; \
r0 = 0; \
l0_%=: if r2 >= 0 goto l1_%=; \
r0 = 0; \
l1_%=: exit; \
" ::: __clobber_all);
}
SEC("socket")
__description("varlen_map_value_access pruning")
__failure __msg("R0 unbounded memory access")
__failure_unpriv __msg_unpriv("R0 leaks addr")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void varlen_map_value_access_pruning(void)
{
asm volatile (" \
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_%=; \
r1 = *(u64*)(r0 + 0); \
w2 = %[max_entries]; \
if r2 s> r1 goto l1_%=; \
w1 = 0; \
l1_%=: w1 <<= 2; \
r0 += r1; \
goto l2_%=; \
l2_%=: r1 = %[test_val_foo]; \
*(u64*)(r0 + 0) = r1; \
l0_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b),
__imm_const(max_entries, MAX_ENTRIES),
__imm_const(test_val_foo, offsetof(struct test_val, foo))
: __clobber_all);
}
SEC("tracepoint")
__description("search pruning: all branches should be verified (nop operation)")
__failure __msg("R6 invalid mem access 'scalar'")
__naked void should_be_verified_nop_operation(void)
{
asm volatile (" \
r2 = r10; \
r2 += -8; \
r1 = 0; \
*(u64*)(r2 + 0) = r1; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
r3 = *(u64*)(r0 + 0); \
if r3 == 0xbeef goto l1_%=; \
r4 = 0; \
goto l2_%=; \
l1_%=: r4 = 1; \
l2_%=: *(u64*)(r10 - 16) = r4; \
call %[bpf_ktime_get_ns]; \
r5 = *(u64*)(r10 - 16); \
if r5 == 0 goto l0_%=; \
r6 = 0; \
r1 = 0xdead; \
*(u64*)(r6 + 0) = r1; \
l0_%=: exit; \
" :
: __imm(bpf_ktime_get_ns),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("socket")
__description("search pruning: all branches should be verified (invalid stack access)")
/* in privileged mode reads from uninitialized stack locations are permitted */
__success __failure_unpriv
__msg_unpriv("invalid read from stack off -16+0 size 8")
__retval(0)
__naked void be_verified_invalid_stack_access(void)
{
asm volatile (" \
r2 = r10; \
r2 += -8; \
r1 = 0; \
*(u64*)(r2 + 0) = r1; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
r3 = *(u64*)(r0 + 0); \
r4 = 0; \
if r3 == 0xbeef goto l1_%=; \
*(u64*)(r10 - 16) = r4; \
goto l2_%=; \
l1_%=: *(u64*)(r10 - 24) = r4; \
l2_%=: call %[bpf_ktime_get_ns]; \
r5 = *(u64*)(r10 - 16); \
l0_%=: exit; \
" :
: __imm(bpf_ktime_get_ns),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("tracepoint")
__description("precision tracking for u32 spill/fill")
__failure __msg("R0 min value is outside of the allowed memory range")
__naked void tracking_for_u32_spill_fill(void)
{
asm volatile (" \
r7 = r1; \
call %[bpf_get_prandom_u32]; \
w6 = 32; \
if r0 == 0 goto l0_%=; \
w6 = 4; \
l0_%=: /* Additional insns to introduce a pruning point. */\
call %[bpf_get_prandom_u32]; \
r3 = 0; \
r3 = 0; \
if r0 == 0 goto l1_%=; \
r3 = 0; \
l1_%=: /* u32 spill/fill */ \
*(u32*)(r10 - 8) = r6; \
r8 = *(u32*)(r10 - 8); \
/* out-of-bound map value access for r6=32 */ \
r1 = 0; \
*(u64*)(r10 - 16) = r1; \
r2 = r10; \
r2 += -16; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l2_%=; \
r0 += r8; \
r1 = *(u32*)(r0 + 0); \
l2_%=: r0 = 0; \
exit; \
" :
: __imm(bpf_get_prandom_u32),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("tracepoint")
__description("precision tracking for u32 spills, u64 fill")
__failure __msg("div by zero")
__naked void for_u32_spills_u64_fill(void)
{
asm volatile (" \
call %[bpf_get_prandom_u32]; \
r6 = r0; \
w7 = 0xffffffff; \
/* Additional insns to introduce a pruning point. */\
r3 = 1; \
r3 = 1; \
r3 = 1; \
r3 = 1; \
call %[bpf_get_prandom_u32]; \
if r0 == 0 goto l0_%=; \
r3 = 1; \
l0_%=: w3 /= 0; \
/* u32 spills, u64 fill */ \
*(u32*)(r10 - 4) = r6; \
*(u32*)(r10 - 8) = r7; \
r8 = *(u64*)(r10 - 8); \
/* if r8 != X goto pc+1 r8 known in fallthrough branch */\
if r8 != 0xffffffff goto l1_%=; \
r3 = 1; \
l1_%=: /* if r8 == X goto pc+1 condition always true on first\
* traversal, so starts backtracking to mark r8 as requiring\
* precision. r7 marked as needing precision. r6 not marked\
* since it's not tracked. \
*/ \
if r8 == 0xffffffff goto l2_%=; \
/* fails if r8 correctly marked unknown after fill. */\
w3 /= 0; \
l2_%=: r0 = 0; \
exit; \
" :
: __imm(bpf_get_prandom_u32)
: __clobber_all);
}
SEC("socket")
__description("allocated_stack")
__success __msg("processed 15 insns")
__success_unpriv __msg_unpriv("") __log_level(1) __retval(0)
__naked void allocated_stack(void)
{
asm volatile (" \
r6 = r1; \
call %[bpf_get_prandom_u32]; \
r7 = r0; \
if r0 == 0 goto l0_%=; \
r0 = 0; \
*(u64*)(r10 - 8) = r6; \
r6 = *(u64*)(r10 - 8); \
*(u8*)(r10 - 9) = r7; \
r7 = *(u8*)(r10 - 9); \
l0_%=: if r0 != 0 goto l1_%=; \
l1_%=: if r0 != 0 goto l2_%=; \
l2_%=: if r0 != 0 goto l3_%=; \
l3_%=: if r0 != 0 goto l4_%=; \
l4_%=: exit; \
" :
: __imm(bpf_get_prandom_u32)
: __clobber_all);
}
/* The test performs a conditional 64-bit write to a stack location
* fp[-8], this is followed by an unconditional 8-bit write to fp[-8],
* then data is read from fp[-8]. This sequence is unsafe.
*
* The test would be mistakenly marked as safe w/o dst register parent
* preservation in verifier.c:copy_register_state() function.
*
* Note the usage of BPF_F_TEST_STATE_FREQ to force creation of the
* checkpoint state after conditional 64-bit assignment.
*/
SEC("socket")
__description("write tracking and register parent chain bug")
/* in privileged mode reads from uninitialized stack locations are permitted */
__success __failure_unpriv
__msg_unpriv("invalid read from stack off -8+1 size 8")
__retval(0) __flag(BPF_F_TEST_STATE_FREQ)
__naked void and_register_parent_chain_bug(void)
{
asm volatile (" \
/* r6 = ktime_get_ns() */ \
call %[bpf_ktime_get_ns]; \
r6 = r0; \
/* r0 = ktime_get_ns() */ \
call %[bpf_ktime_get_ns]; \
/* if r0 > r6 goto +1 */ \
if r0 > r6 goto l0_%=; \
/* *(u64 *)(r10 - 8) = 0xdeadbeef */ \
r0 = 0xdeadbeef; \
*(u64*)(r10 - 8) = r0; \
l0_%=: r1 = 42; \
*(u8*)(r10 - 8) = r1; \
r2 = *(u64*)(r10 - 8); \
/* exit(0) */ \
r0 = 0; \
exit; \
" :
: __imm(bpf_ktime_get_ns)
: __clobber_all);
}
char _license[] SEC("license") = "GPL";