1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/value_adj_spill.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("socket")
__description("map element value is preserved across register spilling")
__success __failure_unpriv __msg_unpriv("R0 leaks addr")
__retval(0)
__naked void is_preserved_across_register_spilling(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_%=; \
r1 = 42; \
*(u64*)(r0 + 0) = r1; \
r1 = r10; \
r1 += -184; \
*(u64*)(r1 + 0) = r0; \
r3 = *(u64*)(r1 + 0); \
r1 = 42; \
*(u64*)(r3 + 0) = r1; \
l0_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b)
: __clobber_all);
}
SEC("socket")
__description("map element value or null is marked on register spilling")
__success __failure_unpriv __msg_unpriv("R0 leaks addr")
__retval(0)
__naked void is_marked_on_register_spilling(void)
{
asm volatile (" \
r2 = r10; \
r2 += -8; \
r1 = 0; \
*(u64*)(r2 + 0) = r1; \
r1 = %[map_hash_48b] ll; \
call %[bpf_map_lookup_elem]; \
r1 = r10; \
r1 += -152; \
*(u64*)(r1 + 0) = r0; \
if r0 == 0 goto l0_%=; \
r3 = *(u64*)(r1 + 0); \
r1 = 42; \
*(u64*)(r3 + 0) = r1; \
l0_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b)
: __clobber_all);
}
char _license[] SEC("license") = "GPL";
|
