1/*-
2 * Copyright (c) 2013 Dmitry Chagin
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer
10 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
| 1/*-
2 * Copyright (c) 2013 Dmitry Chagin
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer
10 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
|
29
30#include "opt_compat.h"
31
32#define __ELF_WORD_SIZE 32
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/elf.h>
37#include <sys/kernel.h>
38#include <sys/lock.h>
39#include <sys/rwlock.h>
40#include <sys/queue.h>
41#include <sys/sysent.h>
42
43#include <vm/vm.h>
44#include <vm/vm_param.h>
45#include <vm/pmap.h>
46#include <vm/vm_extern.h>
47#include <vm/vm_kern.h>
48#include <vm/vm_map.h>
49#include <vm/vm_object.h>
50#include <vm/vm_page.h>
51#include <vm/vm_pager.h>
52
53#include <compat/linux/linux_vdso.h>
54
55SLIST_HEAD(, linux_vdso_sym) __elfN(linux_vdso_syms) =
56 SLIST_HEAD_INITIALIZER(__elfN(linux_vdso_syms));
57
58static int __elfN(symtabindex);
59static int __elfN(symstrindex);
60
61static void
62__elfN(linux_vdso_lookup)(Elf_Ehdr *, struct linux_vdso_sym *);
63
64
65void
66__elfN(linux_vdso_sym_init)(struct linux_vdso_sym *s)
67{
68
69 SLIST_INSERT_HEAD(&__elfN(linux_vdso_syms), s, sym);
70}
71
72vm_object_t
73__elfN(linux_shared_page_init)(char **mapping)
74{
75 vm_page_t m;
76 vm_object_t obj;
77 vm_offset_t addr;
78
79 obj = vm_pager_allocate(OBJT_PHYS, 0, PAGE_SIZE,
80 VM_PROT_DEFAULT, 0, NULL);
81 VM_OBJECT_WLOCK(obj);
82 m = vm_page_grab(obj, 0, VM_ALLOC_NOBUSY | VM_ALLOC_ZERO);
83 m->valid = VM_PAGE_BITS_ALL;
84 VM_OBJECT_WUNLOCK(obj);
85 addr = kva_alloc(PAGE_SIZE);
86 pmap_qenter(addr, &m, 1);
87 *mapping = (char *)addr;
88 return (obj);
89}
90
91void
92__elfN(linux_shared_page_fini)(vm_object_t obj)
93{
94
95 vm_object_deallocate(obj);
96}
97
98void
99__elfN(linux_vdso_fixup)(struct sysentvec *sv)
100{
101 Elf_Ehdr *ehdr;
102 Elf_Shdr *shdr;
103 int i;
104
105 ehdr = (Elf_Ehdr *) sv->sv_sigcode;
106
107 if (!IS_ELF(*ehdr) ||
108 ehdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
109 ehdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
110 ehdr->e_ident[EI_VERSION] != EV_CURRENT ||
111 ehdr->e_shoff == 0 ||
112 ehdr->e_shentsize != sizeof(Elf_Shdr))
113 panic("Linux invalid vdso header.\n");
114
115 if (ehdr->e_type != ET_DYN)
116 panic("Linux invalid vdso header.\n");
117
118 shdr = (Elf_Shdr *) ((caddr_t)ehdr + ehdr->e_shoff);
119
120 __elfN(symtabindex) = -1;
121 __elfN(symstrindex) = -1;
122 for (i = 0; i < ehdr->e_shnum; i++) {
123 if (shdr[i].sh_size == 0)
124 continue;
125 if (shdr[i].sh_type == SHT_DYNSYM) {
126 __elfN(symtabindex) = i;
127 __elfN(symstrindex) = shdr[i].sh_link;
128 }
129 }
130
131 if (__elfN(symtabindex) == -1 || __elfN(symstrindex) == -1)
132 panic("Linux invalid vdso header.\n");
133
134 ehdr->e_ident[EI_OSABI] = ELFOSABI_LINUX;
135}
136
137void
138__elfN(linux_vdso_reloc)(struct sysentvec *sv, int vdso_adjust)
139{
140 struct linux_vdso_sym *lsym;
141 Elf_Ehdr *ehdr;
142 Elf_Phdr *phdr;
143 Elf_Shdr *shdr;
144 Elf_Dyn *dyn;
145 Elf_Sym *sym;
146 int i, symcnt;
147
148 ehdr = (Elf_Ehdr *) sv->sv_sigcode;
149
150 /* Adjust our so relative to the sigcode_base */
151 if (vdso_adjust != 0) {
152 ehdr->e_entry += vdso_adjust;
153 phdr = (Elf_Phdr *)((caddr_t)ehdr + ehdr->e_phoff);
154
155 /* phdrs */
156 for (i = 0; i < ehdr->e_phnum; i++) {
157 phdr[i].p_vaddr += vdso_adjust;
158 if (phdr[i].p_type != PT_DYNAMIC)
159 continue;
160 dyn = (Elf_Dyn *)((caddr_t)ehdr + phdr[i].p_offset);
161 for(; dyn->d_tag != DT_NULL; dyn++) {
162 switch (dyn->d_tag) {
163 case DT_PLTGOT:
164 case DT_HASH:
165 case DT_STRTAB:
166 case DT_SYMTAB:
167 case DT_RELA:
168 case DT_INIT:
169 case DT_FINI:
170 case DT_REL:
171 case DT_DEBUG:
172 case DT_JMPREL:
173 case DT_VERSYM:
174 case DT_VERDEF:
175 case DT_VERNEED:
176 case DT_ADDRRNGLO ... DT_ADDRRNGHI:
177 dyn->d_un.d_ptr += vdso_adjust;
178 break;
179 case DT_ENCODING ... DT_LOOS-1:
180 case DT_LOOS ... DT_HIOS:
181 if (dyn->d_tag >= DT_ENCODING &&
182 (dyn->d_tag & 1) == 0)
183 dyn->d_un.d_ptr += vdso_adjust;
184 break;
185 default:
186 break;
187 }
188 }
189 }
190
191 /* sections */
192 shdr = (Elf_Shdr *)((caddr_t)ehdr + ehdr->e_shoff);
193 for(i = 0; i < ehdr->e_shnum; i++) {
194 if (!(shdr[i].sh_flags & SHF_ALLOC))
195 continue;
196 shdr[i].sh_addr += vdso_adjust;
197 if (shdr[i].sh_type != SHT_SYMTAB &&
198 shdr[i].sh_type != SHT_DYNSYM)
199 continue;
200
201 sym = (Elf_Sym *)((caddr_t)ehdr + shdr[i].sh_offset);
202 symcnt = shdr[i].sh_size / sizeof(*sym);
203
204 for(i = 0; i < symcnt; i++, sym++) {
205 if (sym->st_shndx == SHN_UNDEF ||
206 sym->st_shndx == SHN_ABS)
207 continue;
208 sym->st_value += vdso_adjust;
209 }
210 }
211 }
212
213 SLIST_FOREACH(lsym, &__elfN(linux_vdso_syms), sym)
214 __elfN(linux_vdso_lookup)(ehdr, lsym);
215}
216
217static void
218__elfN(linux_vdso_lookup)(Elf_Ehdr *ehdr, struct linux_vdso_sym *vsym)
219{
220 vm_offset_t strtab, symname;
221 uint32_t symcnt;
222 Elf_Shdr *shdr;
223 int i;
224
225 shdr = (Elf_Shdr *) ((caddr_t)ehdr + ehdr->e_shoff);
226
227 strtab = (vm_offset_t)((caddr_t)ehdr +
228 shdr[__elfN(symstrindex)].sh_offset);
229 Elf_Sym *sym = (Elf_Sym *)((caddr_t)ehdr +
230 shdr[__elfN(symtabindex)].sh_offset);
231 symcnt = shdr[__elfN(symtabindex)].sh_size / sizeof(*sym);
232
233 for (i = 0; i < symcnt; ++i, ++sym) {
234 symname = strtab + sym->st_name;
235 if (strncmp(vsym->symname, (char *)symname, vsym->size) == 0) {
236 *vsym->ptr = (uintptr_t)sym->st_value;
237 break;
238 }
239 }
240}
| 29
30#include "opt_compat.h"
31
32#define __ELF_WORD_SIZE 32
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/elf.h>
37#include <sys/kernel.h>
38#include <sys/lock.h>
39#include <sys/rwlock.h>
40#include <sys/queue.h>
41#include <sys/sysent.h>
42
43#include <vm/vm.h>
44#include <vm/vm_param.h>
45#include <vm/pmap.h>
46#include <vm/vm_extern.h>
47#include <vm/vm_kern.h>
48#include <vm/vm_map.h>
49#include <vm/vm_object.h>
50#include <vm/vm_page.h>
51#include <vm/vm_pager.h>
52
53#include <compat/linux/linux_vdso.h>
54
55SLIST_HEAD(, linux_vdso_sym) __elfN(linux_vdso_syms) =
56 SLIST_HEAD_INITIALIZER(__elfN(linux_vdso_syms));
57
58static int __elfN(symtabindex);
59static int __elfN(symstrindex);
60
61static void
62__elfN(linux_vdso_lookup)(Elf_Ehdr *, struct linux_vdso_sym *);
63
64
65void
66__elfN(linux_vdso_sym_init)(struct linux_vdso_sym *s)
67{
68
69 SLIST_INSERT_HEAD(&__elfN(linux_vdso_syms), s, sym);
70}
71
72vm_object_t
73__elfN(linux_shared_page_init)(char **mapping)
74{
75 vm_page_t m;
76 vm_object_t obj;
77 vm_offset_t addr;
78
79 obj = vm_pager_allocate(OBJT_PHYS, 0, PAGE_SIZE,
80 VM_PROT_DEFAULT, 0, NULL);
81 VM_OBJECT_WLOCK(obj);
82 m = vm_page_grab(obj, 0, VM_ALLOC_NOBUSY | VM_ALLOC_ZERO);
83 m->valid = VM_PAGE_BITS_ALL;
84 VM_OBJECT_WUNLOCK(obj);
85 addr = kva_alloc(PAGE_SIZE);
86 pmap_qenter(addr, &m, 1);
87 *mapping = (char *)addr;
88 return (obj);
89}
90
91void
92__elfN(linux_shared_page_fini)(vm_object_t obj)
93{
94
95 vm_object_deallocate(obj);
96}
97
98void
99__elfN(linux_vdso_fixup)(struct sysentvec *sv)
100{
101 Elf_Ehdr *ehdr;
102 Elf_Shdr *shdr;
103 int i;
104
105 ehdr = (Elf_Ehdr *) sv->sv_sigcode;
106
107 if (!IS_ELF(*ehdr) ||
108 ehdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
109 ehdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
110 ehdr->e_ident[EI_VERSION] != EV_CURRENT ||
111 ehdr->e_shoff == 0 ||
112 ehdr->e_shentsize != sizeof(Elf_Shdr))
113 panic("Linux invalid vdso header.\n");
114
115 if (ehdr->e_type != ET_DYN)
116 panic("Linux invalid vdso header.\n");
117
118 shdr = (Elf_Shdr *) ((caddr_t)ehdr + ehdr->e_shoff);
119
120 __elfN(symtabindex) = -1;
121 __elfN(symstrindex) = -1;
122 for (i = 0; i < ehdr->e_shnum; i++) {
123 if (shdr[i].sh_size == 0)
124 continue;
125 if (shdr[i].sh_type == SHT_DYNSYM) {
126 __elfN(symtabindex) = i;
127 __elfN(symstrindex) = shdr[i].sh_link;
128 }
129 }
130
131 if (__elfN(symtabindex) == -1 || __elfN(symstrindex) == -1)
132 panic("Linux invalid vdso header.\n");
133
134 ehdr->e_ident[EI_OSABI] = ELFOSABI_LINUX;
135}
136
137void
138__elfN(linux_vdso_reloc)(struct sysentvec *sv, int vdso_adjust)
139{
140 struct linux_vdso_sym *lsym;
141 Elf_Ehdr *ehdr;
142 Elf_Phdr *phdr;
143 Elf_Shdr *shdr;
144 Elf_Dyn *dyn;
145 Elf_Sym *sym;
146 int i, symcnt;
147
148 ehdr = (Elf_Ehdr *) sv->sv_sigcode;
149
150 /* Adjust our so relative to the sigcode_base */
151 if (vdso_adjust != 0) {
152 ehdr->e_entry += vdso_adjust;
153 phdr = (Elf_Phdr *)((caddr_t)ehdr + ehdr->e_phoff);
154
155 /* phdrs */
156 for (i = 0; i < ehdr->e_phnum; i++) {
157 phdr[i].p_vaddr += vdso_adjust;
158 if (phdr[i].p_type != PT_DYNAMIC)
159 continue;
160 dyn = (Elf_Dyn *)((caddr_t)ehdr + phdr[i].p_offset);
161 for(; dyn->d_tag != DT_NULL; dyn++) {
162 switch (dyn->d_tag) {
163 case DT_PLTGOT:
164 case DT_HASH:
165 case DT_STRTAB:
166 case DT_SYMTAB:
167 case DT_RELA:
168 case DT_INIT:
169 case DT_FINI:
170 case DT_REL:
171 case DT_DEBUG:
172 case DT_JMPREL:
173 case DT_VERSYM:
174 case DT_VERDEF:
175 case DT_VERNEED:
176 case DT_ADDRRNGLO ... DT_ADDRRNGHI:
177 dyn->d_un.d_ptr += vdso_adjust;
178 break;
179 case DT_ENCODING ... DT_LOOS-1:
180 case DT_LOOS ... DT_HIOS:
181 if (dyn->d_tag >= DT_ENCODING &&
182 (dyn->d_tag & 1) == 0)
183 dyn->d_un.d_ptr += vdso_adjust;
184 break;
185 default:
186 break;
187 }
188 }
189 }
190
191 /* sections */
192 shdr = (Elf_Shdr *)((caddr_t)ehdr + ehdr->e_shoff);
193 for(i = 0; i < ehdr->e_shnum; i++) {
194 if (!(shdr[i].sh_flags & SHF_ALLOC))
195 continue;
196 shdr[i].sh_addr += vdso_adjust;
197 if (shdr[i].sh_type != SHT_SYMTAB &&
198 shdr[i].sh_type != SHT_DYNSYM)
199 continue;
200
201 sym = (Elf_Sym *)((caddr_t)ehdr + shdr[i].sh_offset);
202 symcnt = shdr[i].sh_size / sizeof(*sym);
203
204 for(i = 0; i < symcnt; i++, sym++) {
205 if (sym->st_shndx == SHN_UNDEF ||
206 sym->st_shndx == SHN_ABS)
207 continue;
208 sym->st_value += vdso_adjust;
209 }
210 }
211 }
212
213 SLIST_FOREACH(lsym, &__elfN(linux_vdso_syms), sym)
214 __elfN(linux_vdso_lookup)(ehdr, lsym);
215}
216
217static void
218__elfN(linux_vdso_lookup)(Elf_Ehdr *ehdr, struct linux_vdso_sym *vsym)
219{
220 vm_offset_t strtab, symname;
221 uint32_t symcnt;
222 Elf_Shdr *shdr;
223 int i;
224
225 shdr = (Elf_Shdr *) ((caddr_t)ehdr + ehdr->e_shoff);
226
227 strtab = (vm_offset_t)((caddr_t)ehdr +
228 shdr[__elfN(symstrindex)].sh_offset);
229 Elf_Sym *sym = (Elf_Sym *)((caddr_t)ehdr +
230 shdr[__elfN(symtabindex)].sh_offset);
231 symcnt = shdr[__elfN(symtabindex)].sh_size / sizeof(*sym);
232
233 for (i = 0; i < symcnt; ++i, ++sym) {
234 symname = strtab + sym->st_name;
235 if (strncmp(vsym->symname, (char *)symname, vsym->size) == 0) {
236 *vsym->ptr = (uintptr_t)sym->st_value;
237 break;
238 }
239 }
240}
|