1 // SPDX-License-Identifier: GPL-2.0
2 /* Converted from tools/testing/selftests/bpf/verifier/xadd.c */
3
4 #include <linux/bpf.h>
5 #include <bpf/bpf_helpers.h>
6 #include "bpf_misc.h"
7
8 struct {
9 __uint(type, BPF_MAP_TYPE_HASH);
10 __uint(max_entries, 1);
11 __type(key, long long);
12 __type(value, long long);
13 } map_hash_8b SEC(".maps");
14
15 SEC("tc")
16 __description("xadd/w check unaligned stack")
17 __failure __msg("misaligned stack access off")
xadd_w_check_unaligned_stack(void)18 __naked void xadd_w_check_unaligned_stack(void)
19 {
20 asm volatile (" \
21 r0 = 1; \
22 *(u64*)(r10 - 8) = r0; \
23 lock *(u32 *)(r10 - 7) += w0; \
24 r0 = *(u64*)(r10 - 8); \
25 exit; \
26 " ::: __clobber_all);
27 }
28
29 SEC("tc")
30 __description("xadd/w check unaligned map")
31 __failure __msg("misaligned value access off")
xadd_w_check_unaligned_map(void)32 __naked void xadd_w_check_unaligned_map(void)
33 {
34 asm volatile (" \
35 r1 = 0; \
36 *(u64*)(r10 - 8) = r1; \
37 r2 = r10; \
38 r2 += -8; \
39 r1 = %[map_hash_8b] ll; \
40 call %[bpf_map_lookup_elem]; \
41 if r0 != 0 goto l0_%=; \
42 exit; \
43 l0_%=: r1 = 1; \
44 lock *(u32 *)(r0 + 3) += w1; \
45 r0 = *(u32*)(r0 + 3); \
46 exit; \
47 " :
48 : __imm(bpf_map_lookup_elem),
49 __imm_addr(map_hash_8b)
50 : __clobber_all);
51 }
52
53 SEC("xdp")
54 __description("xadd/w check unaligned pkt")
55 __failure __msg("BPF_ATOMIC stores into R2 pkt is not allowed")
__flag(BPF_F_ANY_ALIGNMENT)56 __flag(BPF_F_ANY_ALIGNMENT)
57 __naked void xadd_w_check_unaligned_pkt(void)
58 {
59 asm volatile (" \
60 r2 = *(u32*)(r1 + %[xdp_md_data]); \
61 r3 = *(u32*)(r1 + %[xdp_md_data_end]); \
62 r1 = r2; \
63 r1 += 8; \
64 if r1 < r3 goto l0_%=; \
65 r0 = 99; \
66 goto l1_%=; \
67 l0_%=: r0 = 1; \
68 r1 = 0; \
69 *(u32*)(r2 + 0) = r1; \
70 r1 = 0; \
71 *(u32*)(r2 + 3) = r1; \
72 lock *(u32 *)(r2 + 1) += w0; \
73 lock *(u32 *)(r2 + 2) += w0; \
74 r0 = *(u32*)(r2 + 1); \
75 l1_%=: exit; \
76 " :
77 : __imm_const(xdp_md_data, offsetof(struct xdp_md, data)),
78 __imm_const(xdp_md_data_end, offsetof(struct xdp_md, data_end))
79 : __clobber_all);
80 }
81
82 SEC("tc")
83 __description("xadd/w check whether src/dst got mangled, 1")
84 __success __retval(3)
src_dst_got_mangled_1(void)85 __naked void src_dst_got_mangled_1(void)
86 {
87 asm volatile (" \
88 r0 = 1; \
89 r6 = r0; \
90 r7 = r10; \
91 *(u64*)(r10 - 8) = r0; \
92 lock *(u64 *)(r10 - 8) += r0; \
93 lock *(u64 *)(r10 - 8) += r0; \
94 if r6 != r0 goto l0_%=; \
95 if r7 != r10 goto l0_%=; \
96 r0 = *(u64*)(r10 - 8); \
97 exit; \
98 l0_%=: r0 = 42; \
99 exit; \
100 " ::: __clobber_all);
101 }
102
103 SEC("tc")
104 __description("xadd/w check whether src/dst got mangled, 2")
105 __success __retval(3)
src_dst_got_mangled_2(void)106 __naked void src_dst_got_mangled_2(void)
107 {
108 asm volatile (" \
109 r0 = 1; \
110 r6 = r0; \
111 r7 = r10; \
112 *(u32*)(r10 - 8) = r0; \
113 lock *(u32 *)(r10 - 8) += w0; \
114 lock *(u32 *)(r10 - 8) += w0; \
115 if r6 != r0 goto l0_%=; \
116 if r7 != r10 goto l0_%=; \
117 r0 = *(u32*)(r10 - 8); \
118 exit; \
119 l0_%=: r0 = 42; \
120 exit; \
121 " ::: __clobber_all);
122 }
123
124 char _license[] SEC("license") = "GPL";
125