1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright 2020, Sandipan Das, IBM Corp.
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun #ifndef _SELFTESTS_POWERPC_PKEYS_H
7*4882a593Smuzhiyun #define _SELFTESTS_POWERPC_PKEYS_H
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <sys/mman.h>
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include "reg.h"
12*4882a593Smuzhiyun #include "utils.h"
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun /*
15*4882a593Smuzhiyun * Older versions of libc use the Intel-specific access rights.
16*4882a593Smuzhiyun * Hence, override the definitions as they might be incorrect.
17*4882a593Smuzhiyun */
18*4882a593Smuzhiyun #undef PKEY_DISABLE_ACCESS
19*4882a593Smuzhiyun #define PKEY_DISABLE_ACCESS 0x3
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun #undef PKEY_DISABLE_WRITE
22*4882a593Smuzhiyun #define PKEY_DISABLE_WRITE 0x2
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun #undef PKEY_DISABLE_EXECUTE
25*4882a593Smuzhiyun #define PKEY_DISABLE_EXECUTE 0x4
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun /* Older versions of libc do not not define this */
28*4882a593Smuzhiyun #ifndef SEGV_PKUERR
29*4882a593Smuzhiyun #define SEGV_PKUERR 4
30*4882a593Smuzhiyun #endif
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun #define SI_PKEY_OFFSET 0x20
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun #define __NR_pkey_mprotect 386
35*4882a593Smuzhiyun #define __NR_pkey_alloc 384
36*4882a593Smuzhiyun #define __NR_pkey_free 385
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun #define PKEY_BITS_PER_PKEY 2
39*4882a593Smuzhiyun #define NR_PKEYS 32
40*4882a593Smuzhiyun #define PKEY_BITS_MASK ((1UL << PKEY_BITS_PER_PKEY) - 1)
41*4882a593Smuzhiyun
pkeyreg_get(void)42*4882a593Smuzhiyun inline unsigned long pkeyreg_get(void)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun return mfspr(SPRN_AMR);
45*4882a593Smuzhiyun }
46*4882a593Smuzhiyun
pkeyreg_set(unsigned long amr)47*4882a593Smuzhiyun inline void pkeyreg_set(unsigned long amr)
48*4882a593Smuzhiyun {
49*4882a593Smuzhiyun set_amr(amr);
50*4882a593Smuzhiyun }
51*4882a593Smuzhiyun
pkey_set_rights(int pkey,unsigned long rights)52*4882a593Smuzhiyun void pkey_set_rights(int pkey, unsigned long rights)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun unsigned long amr, shift;
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun shift = (NR_PKEYS - pkey - 1) * PKEY_BITS_PER_PKEY;
57*4882a593Smuzhiyun amr = pkeyreg_get();
58*4882a593Smuzhiyun amr &= ~(PKEY_BITS_MASK << shift);
59*4882a593Smuzhiyun amr |= (rights & PKEY_BITS_MASK) << shift;
60*4882a593Smuzhiyun pkeyreg_set(amr);
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun
sys_pkey_mprotect(void * addr,size_t len,int prot,int pkey)63*4882a593Smuzhiyun int sys_pkey_mprotect(void *addr, size_t len, int prot, int pkey)
64*4882a593Smuzhiyun {
65*4882a593Smuzhiyun return syscall(__NR_pkey_mprotect, addr, len, prot, pkey);
66*4882a593Smuzhiyun }
67*4882a593Smuzhiyun
sys_pkey_alloc(unsigned long flags,unsigned long rights)68*4882a593Smuzhiyun int sys_pkey_alloc(unsigned long flags, unsigned long rights)
69*4882a593Smuzhiyun {
70*4882a593Smuzhiyun return syscall(__NR_pkey_alloc, flags, rights);
71*4882a593Smuzhiyun }
72*4882a593Smuzhiyun
sys_pkey_free(int pkey)73*4882a593Smuzhiyun int sys_pkey_free(int pkey)
74*4882a593Smuzhiyun {
75*4882a593Smuzhiyun return syscall(__NR_pkey_free, pkey);
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun
pkeys_unsupported(void)78*4882a593Smuzhiyun int pkeys_unsupported(void)
79*4882a593Smuzhiyun {
80*4882a593Smuzhiyun bool hash_mmu = false;
81*4882a593Smuzhiyun int pkey;
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun /* Protection keys are currently supported on Hash MMU only */
84*4882a593Smuzhiyun FAIL_IF(using_hash_mmu(&hash_mmu));
85*4882a593Smuzhiyun SKIP_IF(!hash_mmu);
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun /* Check if the system call is supported */
88*4882a593Smuzhiyun pkey = sys_pkey_alloc(0, 0);
89*4882a593Smuzhiyun SKIP_IF(pkey < 0);
90*4882a593Smuzhiyun sys_pkey_free(pkey);
91*4882a593Smuzhiyun
92*4882a593Smuzhiyun return 0;
93*4882a593Smuzhiyun }
94*4882a593Smuzhiyun
siginfo_pkey(siginfo_t * si)95*4882a593Smuzhiyun int siginfo_pkey(siginfo_t *si)
96*4882a593Smuzhiyun {
97*4882a593Smuzhiyun /*
98*4882a593Smuzhiyun * In older versions of libc, siginfo_t does not have si_pkey as
99*4882a593Smuzhiyun * a member.
100*4882a593Smuzhiyun */
101*4882a593Smuzhiyun #ifdef si_pkey
102*4882a593Smuzhiyun return si->si_pkey;
103*4882a593Smuzhiyun #else
104*4882a593Smuzhiyun return *((int *)(((char *) si) + SI_PKEY_OFFSET));
105*4882a593Smuzhiyun #endif
106*4882a593Smuzhiyun }
107*4882a593Smuzhiyun
108*4882a593Smuzhiyun #define pkey_rights(r) ({ \
109*4882a593Smuzhiyun static char buf[4] = "rwx"; \
110*4882a593Smuzhiyun unsigned int amr_bits; \
111*4882a593Smuzhiyun if ((r) & PKEY_DISABLE_EXECUTE) \
112*4882a593Smuzhiyun buf[2] = '-'; \
113*4882a593Smuzhiyun amr_bits = (r) & PKEY_BITS_MASK; \
114*4882a593Smuzhiyun if (amr_bits & PKEY_DISABLE_WRITE) \
115*4882a593Smuzhiyun buf[1] = '-'; \
116*4882a593Smuzhiyun if (amr_bits & PKEY_DISABLE_ACCESS & ~PKEY_DISABLE_WRITE) \
117*4882a593Smuzhiyun buf[0] = '-'; \
118*4882a593Smuzhiyun buf; \
119*4882a593Smuzhiyun })
120*4882a593Smuzhiyun
next_pkey_rights(unsigned long rights)121*4882a593Smuzhiyun unsigned long next_pkey_rights(unsigned long rights)
122*4882a593Smuzhiyun {
123*4882a593Smuzhiyun if (rights == PKEY_DISABLE_ACCESS)
124*4882a593Smuzhiyun return PKEY_DISABLE_EXECUTE;
125*4882a593Smuzhiyun else if (rights == (PKEY_DISABLE_ACCESS | PKEY_DISABLE_EXECUTE))
126*4882a593Smuzhiyun return 0;
127*4882a593Smuzhiyun
128*4882a593Smuzhiyun if ((rights & PKEY_BITS_MASK) == 0)
129*4882a593Smuzhiyun rights |= PKEY_DISABLE_WRITE;
130*4882a593Smuzhiyun else if ((rights & PKEY_BITS_MASK) == PKEY_DISABLE_WRITE)
131*4882a593Smuzhiyun rights |= PKEY_DISABLE_ACCESS;
132*4882a593Smuzhiyun
133*4882a593Smuzhiyun return rights;
134*4882a593Smuzhiyun }
135*4882a593Smuzhiyun
136*4882a593Smuzhiyun #endif /* _SELFTESTS_POWERPC_PKEYS_H */
137