xref: /linux/tools/testing/selftests/bpf/progs/verifier_value_adj_spill.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Converted from tools/testing/selftests/bpf/verifier/value_adj_spill.c */
3 
4 #include <linux/bpf.h>
5 #include <bpf/bpf_helpers.h>
6 #include "bpf_misc.h"
7 
8 #define MAX_ENTRIES 11
9 
10 struct test_val {
11 	unsigned int index;
12 	int foo[MAX_ENTRIES];
13 };
14 
15 struct {
16 	__uint(type, BPF_MAP_TYPE_HASH);
17 	__uint(max_entries, 1);
18 	__type(key, long long);
19 	__type(value, struct test_val);
20 } map_hash_48b SEC(".maps");
21 
22 SEC("socket")
23 __description("map element value is preserved across register spilling")
24 __success __failure_unpriv __msg_unpriv("R0 leaks addr")
25 __retval(0)
26 __naked void is_preserved_across_register_spilling(void)
27 {
28 	asm volatile ("					\
29 	r2 = r10;					\
30 	r2 += -8;					\
31 	r1 = 0;						\
32 	*(u64*)(r2 + 0) = r1;				\
33 	r1 = %[map_hash_48b] ll;			\
34 	call %[bpf_map_lookup_elem];			\
35 	if r0 == 0 goto l0_%=;				\
36 	r1 = 42;					\
37 	*(u64*)(r0 + 0) = r1;				\
38 	r1 = r10;					\
39 	r1 += -184;					\
40 	*(u64*)(r1 + 0) = r0;				\
41 	r3 = *(u64*)(r1 + 0);				\
42 	r1 = 42;					\
43 	*(u64*)(r3 + 0) = r1;				\
44 l0_%=:	exit;						\
45 "	:
46 	: __imm(bpf_map_lookup_elem),
47 	  __imm_addr(map_hash_48b)
48 	: __clobber_all);
49 }
50 
51 SEC("socket")
52 __description("map element value or null is marked on register spilling")
53 __success __failure_unpriv __msg_unpriv("R0 leaks addr")
54 __retval(0)
55 __naked void is_marked_on_register_spilling(void)
56 {
57 	asm volatile ("					\
58 	r2 = r10;					\
59 	r2 += -8;					\
60 	r1 = 0;						\
61 	*(u64*)(r2 + 0) = r1;				\
62 	r1 = %[map_hash_48b] ll;			\
63 	call %[bpf_map_lookup_elem];			\
64 	r1 = r10;					\
65 	r1 += -152;					\
66 	*(u64*)(r1 + 0) = r0;				\
67 	if r0 == 0 goto l0_%=;				\
68 	r3 = *(u64*)(r1 + 0);				\
69 	r1 = 42;					\
70 	*(u64*)(r3 + 0) = r1;				\
71 l0_%=:	exit;						\
72 "	:
73 	: __imm(bpf_map_lookup_elem),
74 	  __imm_addr(map_hash_48b)
75 	: __clobber_all);
76 }
77 
78 char _license[] SEC("license") = "GPL";
79