1 // SPDX-License-Identifier: GPL-2.0
2 /* Converted from tools/testing/selftests/bpf/verifier/ctx.c */
3
4 #include <linux/bpf.h>
5 #include <bpf/bpf_helpers.h>
6 #include "bpf_misc.h"
7
8 SEC("tc")
9 __description("context stores via BPF_ATOMIC")
10 __failure __msg("BPF_ATOMIC stores into R1 ctx is not allowed")
11 __naked void context_stores_via_bpf_atomic(void)
12 {
13 asm volatile (" \
14 r0 = 0; \
15 lock *(u32 *)(r1 + %[__sk_buff_mark]) += w0; \
16 exit; \
17 " :
18 : __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
19 : __clobber_all);
20 }
21
22 SEC("tc")
23 __description("arithmetic ops make PTR_TO_CTX unusable")
24 __failure __msg("dereference of modified ctx ptr")
25 __naked void make_ptr_to_ctx_unusable(void)
26 {
27 asm volatile (" \
28 r1 += %[__imm_0]; \
29 r0 = *(u32*)(r1 + %[__sk_buff_mark]); \
30 exit; \
31 " :
32 : __imm_const(__imm_0,
33 offsetof(struct __sk_buff, data) - offsetof(struct __sk_buff, mark)),
34 __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
35 : __clobber_all);
36 }
37
38 SEC("tc")
39 __description("pass unmodified ctx pointer to helper")
40 __success __retval(0)
41 __naked void unmodified_ctx_pointer_to_helper(void)
42 {
43 asm volatile (" \
44 r2 = 0; \
45 call %[bpf_csum_update]; \
46 r0 = 0; \
47 exit; \
48 " :
49 : __imm(bpf_csum_update)
50 : __clobber_all);
51 }
52
53 SEC("tc")
54 __description("pass modified ctx pointer to helper, 1")
55 __failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
56 __naked void ctx_pointer_to_helper_1(void)
57 {
58 asm volatile (" \
59 r1 += -612; \
60 r2 = 0; \
61 call %[bpf_csum_update]; \
62 r0 = 0; \
63 exit; \
64 " :
65 : __imm(bpf_csum_update)
66 : __clobber_all);
67 }
68
69 SEC("socket")
70 __description("pass modified ctx pointer to helper, 2")
71 __failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
72 __failure_unpriv __msg_unpriv("negative offset ctx ptr R1 off=-612 disallowed")
73 __naked void ctx_pointer_to_helper_2(void)
74 {
75 asm volatile (" \
76 r1 += -612; \
77 call %[bpf_get_socket_cookie]; \
78 r0 = 0; \
79 exit; \
80 " :
81 : __imm(bpf_get_socket_cookie)
82 : __clobber_all);
83 }
84
85 SEC("tc")
86 __description("pass modified ctx pointer to helper, 3")
87 __failure __msg("variable ctx access var_off=(0x0; 0x4)")
88 __naked void ctx_pointer_to_helper_3(void)
89 {
90 asm volatile (" \
91 r3 = *(u32*)(r1 + 0); \
92 r3 &= 4; \
93 r1 += r3; \
94 r2 = 0; \
95 call %[bpf_csum_update]; \
96 r0 = 0; \
97 exit; \
98 " :
99 : __imm(bpf_csum_update)
100 : __clobber_all);
101 }
102
103 SEC("cgroup/sendmsg6")
104 __description("pass ctx or null check, 1: ctx")
105 __success
106 __naked void or_null_check_1_ctx(void)
107 {
108 asm volatile (" \
109 call %[bpf_get_netns_cookie]; \
110 r0 = 0; \
111 exit; \
112 " :
113 : __imm(bpf_get_netns_cookie)
114 : __clobber_all);
115 }
116
117 SEC("cgroup/sendmsg6")
118 __description("pass ctx or null check, 2: null")
119 __success
120 __naked void or_null_check_2_null(void)
121 {
122 asm volatile (" \
123 r1 = 0; \
124 call %[bpf_get_netns_cookie]; \
125 r0 = 0; \
126 exit; \
127 " :
128 : __imm(bpf_get_netns_cookie)
129 : __clobber_all);
130 }
131
132 SEC("cgroup/sendmsg6")
133 __description("pass ctx or null check, 3: 1")
134 __failure __msg("R1 type=scalar expected=ctx")
135 __naked void or_null_check_3_1(void)
136 {
137 asm volatile (" \
138 r1 = 1; \
139 call %[bpf_get_netns_cookie]; \
140 r0 = 0; \
141 exit; \
142 " :
143 : __imm(bpf_get_netns_cookie)
144 : __clobber_all);
145 }
146
147 SEC("cgroup/sendmsg6")
148 __description("pass ctx or null check, 4: ctx - const")
149 __failure __msg("negative offset ctx ptr R1 off=-612 disallowed")
150 __naked void null_check_4_ctx_const(void)
151 {
152 asm volatile (" \
153 r1 += -612; \
154 call %[bpf_get_netns_cookie]; \
155 r0 = 0; \
156 exit; \
157 " :
158 : __imm(bpf_get_netns_cookie)
159 : __clobber_all);
160 }
161
162 SEC("cgroup/connect4")
163 __description("pass ctx or null check, 5: null (connect)")
164 __success
165 __naked void null_check_5_null_connect(void)
166 {
167 asm volatile (" \
168 r1 = 0; \
169 call %[bpf_get_netns_cookie]; \
170 r0 = 0; \
171 exit; \
172 " :
173 : __imm(bpf_get_netns_cookie)
174 : __clobber_all);
175 }
176
177 SEC("cgroup/post_bind4")
178 __description("pass ctx or null check, 6: null (bind)")
179 __success
180 __naked void null_check_6_null_bind(void)
181 {
182 asm volatile (" \
183 r1 = 0; \
184 call %[bpf_get_netns_cookie]; \
185 r0 = 0; \
186 exit; \
187 " :
188 : __imm(bpf_get_netns_cookie)
189 : __clobber_all);
190 }
191
192 SEC("cgroup/post_bind4")
193 __description("pass ctx or null check, 7: ctx (bind)")
194 __success
195 __naked void null_check_7_ctx_bind(void)
196 {
197 asm volatile (" \
198 call %[bpf_get_socket_cookie]; \
199 r0 = 0; \
200 exit; \
201 " :
202 : __imm(bpf_get_socket_cookie)
203 : __clobber_all);
204 }
205
206 SEC("cgroup/post_bind4")
207 __description("pass ctx or null check, 8: null (bind)")
208 __failure __msg("R1 type=scalar expected=ctx")
209 __naked void null_check_8_null_bind(void)
210 {
211 asm volatile (" \
212 r1 = 0; \
213 call %[bpf_get_socket_cookie]; \
214 r0 = 0; \
215 exit; \
216 " :
217 : __imm(bpf_get_socket_cookie)
218 : __clobber_all);
219 }
220
221 char _license[] SEC("license") = "GPL";
222
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