Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/* Converted from tools/testing/selftests/bpf/verifier/map_ptr.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
10struct test_val {
11 unsigned int index;
12 int foo[MAX_ENTRIES];
13};
14
15struct {
16 __uint(type, BPF_MAP_TYPE_ARRAY);
17 __uint(max_entries, 1);
18 __type(key, int);
19 __type(value, struct test_val);
20} map_array_48b SEC(".maps");
21
22struct other_val {
23 long long foo;
24 long long bar;
25};
26
27struct {
28 __uint(type, BPF_MAP_TYPE_HASH);
29 __uint(max_entries, 1);
30 __type(key, long long);
31 __type(value, struct other_val);
32} map_hash_16b SEC(".maps");
33
34SEC("socket")
35__description("bpf_map_ptr: read with negative offset rejected")
36__failure __msg("R1 is bpf_array invalid negative access: off=-8")
37__failure_unpriv
38__msg_unpriv("access is allowed only to CAP_PERFMON and CAP_SYS_ADMIN")
39__naked void read_with_negative_offset_rejected(void)
40{
41 asm volatile (" \
42 r1 = r10; \
43 r1 = %[map_array_48b] ll; \
44 r6 = *(u64*)(r1 - 8); \
45 r0 = 1; \
46 exit; \
47" :
48 : __imm_addr(map_array_48b)
49 : __clobber_all);
50}
51
52SEC("socket")
53__description("bpf_map_ptr: write rejected")
54__failure __msg("only read from bpf_array is supported")
55__failure_unpriv
56__msg_unpriv("access is allowed only to CAP_PERFMON and CAP_SYS_ADMIN")
57__naked void bpf_map_ptr_write_rejected(void)
58{
59 asm volatile (" \
60 r0 = 0; \
61 *(u64*)(r10 - 8) = r0; \
62 r2 = r10; \
63 r2 += -8; \
64 r1 = %[map_array_48b] ll; \
65 *(u64*)(r1 + 0) = r2; \
66 r0 = 1; \
67 exit; \
68" :
69 : __imm_addr(map_array_48b)
70 : __clobber_all);
71}
72
73/* The first element of struct bpf_map is a SHA256 hash of 32 bytes, accessing
74 * into this array is valid. The opts field is now at offset 33.
75 */
76SEC("socket")
77__description("bpf_map_ptr: read non-existent field rejected")
78__failure
79__msg("cannot access ptr member ops with moff 32 in struct bpf_map with off 33 size 4")
80__failure_unpriv
81__msg_unpriv("access is allowed only to CAP_PERFMON and CAP_SYS_ADMIN")
82__flag(BPF_F_ANY_ALIGNMENT)
83__naked void read_non_existent_field_rejected(void)
84{
85 asm volatile (" \
86 r6 = 0; \
87 r1 = %[map_array_48b] ll; \
88 r6 = *(u32*)(r1 + 33); \
89 r0 = 1; \
90 exit; \
91" :
92 : __imm_addr(map_array_48b)
93 : __clobber_all);
94}
95
96SEC("socket")
97__description("bpf_map_ptr: read ops field accepted")
98__success __failure_unpriv
99__msg_unpriv("access is allowed only to CAP_PERFMON and CAP_SYS_ADMIN")
100__retval(1)
101__naked void ptr_read_ops_field_accepted(void)
102{
103 asm volatile (" \
104 r6 = 0; \
105 r1 = %[map_array_48b] ll; \
106 r6 = *(u64*)(r1 + 0); \
107 r0 = 1; \
108 exit; \
109" :
110 : __imm_addr(map_array_48b)
111 : __clobber_all);
112}
113
114SEC("socket")
115__description("bpf_map_ptr: r = 0, map_ptr = map_ptr + r")
116__success __failure_unpriv
117__msg_unpriv("R1 has pointer with unsupported alu operation")
118__retval(0)
119__naked void map_ptr_map_ptr_r(void)
120{
121 asm volatile (" \
122 r0 = 0; \
123 *(u64*)(r10 - 8) = r0; \
124 r2 = r10; \
125 r2 += -8; \
126 r0 = 0; \
127 r1 = %[map_hash_16b] ll; \
128 r1 += r0; \
129 call %[bpf_map_lookup_elem]; \
130 r0 = 0; \
131 exit; \
132" :
133 : __imm(bpf_map_lookup_elem),
134 __imm_addr(map_hash_16b)
135 : __clobber_all);
136}
137
138SEC("socket")
139__description("bpf_map_ptr: r = 0, r = r + map_ptr")
140__success __failure_unpriv
141__msg_unpriv("R0 has pointer with unsupported alu operation")
142__retval(0)
143__naked void _0_r_r_map_ptr(void)
144{
145 asm volatile (" \
146 r0 = 0; \
147 *(u64*)(r10 - 8) = r0; \
148 r2 = r10; \
149 r2 += -8; \
150 r1 = 0; \
151 r0 = %[map_hash_16b] ll; \
152 r1 += r0; \
153 call %[bpf_map_lookup_elem]; \
154 r0 = 0; \
155 exit; \
156" :
157 : __imm(bpf_map_lookup_elem),
158 __imm_addr(map_hash_16b)
159 : __clobber_all);
160}
161
162char _license[] SEC("license") = "GPL";