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1/*
2 * linux/arch/arm/kernel/module.c
3 *
4 * Copyright (C) 2002 Russell King.
5 * Modified for nommu by Hyok S. Choi
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * Module allocation method suggested by Andi Kleen.
12 */
13#include <linux/module.h>
14#include <linux/moduleloader.h>
15#include <linux/kernel.h>
16#include <linux/mm.h>
17#include <linux/elf.h>
18#include <linux/vmalloc.h>
19#include <linux/fs.h>
20#include <linux/string.h>
21#include <linux/gfp.h>
22
23#include <asm/pgtable.h>
24#include <asm/sections.h>
25#include <asm/smp_plat.h>
26#include <asm/unwind.h>
27
28#ifdef CONFIG_XIP_KERNEL
29/*
30 * The XIP kernel text is mapped in the module area for modules and
31 * some other stuff to work without any indirect relocations.
32 * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
33 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
34 */
35#undef MODULES_VADDR
36#define MODULES_VADDR (((unsigned long)_etext + ~PGDIR_MASK) & PGDIR_MASK)
37#endif
38
39#ifdef CONFIG_MMU
40void *module_alloc(unsigned long size)
41{
42 return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
43 GFP_KERNEL, PAGE_KERNEL_EXEC, -1,
44 __builtin_return_address(0));
45}
46#endif
47
48int
49apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
50 unsigned int relindex, struct module *module)
51{
52 Elf32_Shdr *symsec = sechdrs + symindex;
53 Elf32_Shdr *relsec = sechdrs + relindex;
54 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
55 Elf32_Rel *rel = (void *)relsec->sh_addr;
56 unsigned int i;
57
58 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
59 unsigned long loc;
60 Elf32_Sym *sym;
61 const char *symname;
62 s32 offset;
63#ifdef CONFIG_THUMB2_KERNEL
64 u32 upper, lower, sign, j1, j2;
65#endif
66
67 offset = ELF32_R_SYM(rel->r_info);
68 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
69 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
70 module->name, relindex, i);
71 return -ENOEXEC;
72 }
73
74 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
75 symname = strtab + sym->st_name;
76
77 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
78 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
79 module->name, relindex, i, symname,
80 rel->r_offset, dstsec->sh_size);
81 return -ENOEXEC;
82 }
83
84 loc = dstsec->sh_addr + rel->r_offset;
85
86 switch (ELF32_R_TYPE(rel->r_info)) {
87 case R_ARM_NONE:
88 /* ignore */
89 break;
90
91 case R_ARM_ABS32:
92 *(u32 *)loc += sym->st_value;
93 break;
94
95 case R_ARM_PC24:
96 case R_ARM_CALL:
97 case R_ARM_JUMP24:
98 offset = (*(u32 *)loc & 0x00ffffff) << 2;
99 if (offset & 0x02000000)
100 offset -= 0x04000000;
101
102 offset += sym->st_value - loc;
103 if (offset & 3 ||
104 offset <= (s32)0xfe000000 ||
105 offset >= (s32)0x02000000) {
106 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
107 module->name, relindex, i, symname,
108 ELF32_R_TYPE(rel->r_info), loc,
109 sym->st_value);
110 return -ENOEXEC;
111 }
112
113 offset >>= 2;
114
115 *(u32 *)loc &= 0xff000000;
116 *(u32 *)loc |= offset & 0x00ffffff;
117 break;
118
119 case R_ARM_V4BX:
120 /* Preserve Rm and the condition code. Alter
121 * other bits to re-code instruction as
122 * MOV PC,Rm.
123 */
124 *(u32 *)loc &= 0xf000000f;
125 *(u32 *)loc |= 0x01a0f000;
126 break;
127
128 case R_ARM_PREL31:
129 offset = *(u32 *)loc + sym->st_value - loc;
130 *(u32 *)loc = offset & 0x7fffffff;
131 break;
132
133 case R_ARM_MOVW_ABS_NC:
134 case R_ARM_MOVT_ABS:
135 offset = *(u32 *)loc;
136 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
137 offset = (offset ^ 0x8000) - 0x8000;
138
139 offset += sym->st_value;
140 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
141 offset >>= 16;
142
143 *(u32 *)loc &= 0xfff0f000;
144 *(u32 *)loc |= ((offset & 0xf000) << 4) |
145 (offset & 0x0fff);
146 break;
147
148#ifdef CONFIG_THUMB2_KERNEL
149 case R_ARM_THM_CALL:
150 case R_ARM_THM_JUMP24:
151 upper = *(u16 *)loc;
152 lower = *(u16 *)(loc + 2);
153
154 /*
155 * 25 bit signed address range (Thumb-2 BL and B.W
156 * instructions):
157 * S:I1:I2:imm10:imm11:0
158 * where:
159 * S = upper[10] = offset[24]
160 * I1 = ~(J1 ^ S) = offset[23]
161 * I2 = ~(J2 ^ S) = offset[22]
162 * imm10 = upper[9:0] = offset[21:12]
163 * imm11 = lower[10:0] = offset[11:1]
164 * J1 = lower[13]
165 * J2 = lower[11]
166 */
167 sign = (upper >> 10) & 1;
168 j1 = (lower >> 13) & 1;
169 j2 = (lower >> 11) & 1;
170 offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
171 ((~(j2 ^ sign) & 1) << 22) |
172 ((upper & 0x03ff) << 12) |
173 ((lower & 0x07ff) << 1);
174 if (offset & 0x01000000)
175 offset -= 0x02000000;
176 offset += sym->st_value - loc;
177
178 /*
179 * For function symbols, only Thumb addresses are
180 * allowed (no interworking).
181 *
182 * For non-function symbols, the destination
183 * has no specific ARM/Thumb disposition, so
184 * the branch is resolved under the assumption
185 * that interworking is not required.
186 */
187 if ((ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
188 !(offset & 1)) ||
189 offset <= (s32)0xff000000 ||
190 offset >= (s32)0x01000000) {
191 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
192 module->name, relindex, i, symname,
193 ELF32_R_TYPE(rel->r_info), loc,
194 sym->st_value);
195 return -ENOEXEC;
196 }
197
198 sign = (offset >> 24) & 1;
199 j1 = sign ^ (~(offset >> 23) & 1);
200 j2 = sign ^ (~(offset >> 22) & 1);
201 *(u16 *)loc = (u16)((upper & 0xf800) | (sign << 10) |
202 ((offset >> 12) & 0x03ff));
203 *(u16 *)(loc + 2) = (u16)((lower & 0xd000) |
204 (j1 << 13) | (j2 << 11) |
205 ((offset >> 1) & 0x07ff));
206 break;
207
208 case R_ARM_THM_MOVW_ABS_NC:
209 case R_ARM_THM_MOVT_ABS:
210 upper = *(u16 *)loc;
211 lower = *(u16 *)(loc + 2);
212
213 /*
214 * MOVT/MOVW instructions encoding in Thumb-2:
215 *
216 * i = upper[10]
217 * imm4 = upper[3:0]
218 * imm3 = lower[14:12]
219 * imm8 = lower[7:0]
220 *
221 * imm16 = imm4:i:imm3:imm8
222 */
223 offset = ((upper & 0x000f) << 12) |
224 ((upper & 0x0400) << 1) |
225 ((lower & 0x7000) >> 4) | (lower & 0x00ff);
226 offset = (offset ^ 0x8000) - 0x8000;
227 offset += sym->st_value;
228
229 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS)
230 offset >>= 16;
231
232 *(u16 *)loc = (u16)((upper & 0xfbf0) |
233 ((offset & 0xf000) >> 12) |
234 ((offset & 0x0800) >> 1));
235 *(u16 *)(loc + 2) = (u16)((lower & 0x8f00) |
236 ((offset & 0x0700) << 4) |
237 (offset & 0x00ff));
238 break;
239#endif
240
241 default:
242 printk(KERN_ERR "%s: unknown relocation: %u\n",
243 module->name, ELF32_R_TYPE(rel->r_info));
244 return -ENOEXEC;
245 }
246 }
247 return 0;
248}
249
250struct mod_unwind_map {
251 const Elf_Shdr *unw_sec;
252 const Elf_Shdr *txt_sec;
253};
254
255static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
256 const Elf_Shdr *sechdrs, const char *name)
257{
258 const Elf_Shdr *s, *se;
259 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
260
261 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
262 if (strcmp(name, secstrs + s->sh_name) == 0)
263 return s;
264
265 return NULL;
266}
267
268extern void fixup_pv_table(const void *, unsigned long);
269extern void fixup_smp(const void *, unsigned long);
270
271int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
272 struct module *mod)
273{
274 const Elf_Shdr *s = NULL;
275#ifdef CONFIG_ARM_UNWIND
276 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
277 const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
278 struct mod_unwind_map maps[ARM_SEC_MAX];
279 int i;
280
281 memset(maps, 0, sizeof(maps));
282
283 for (s = sechdrs; s < sechdrs_end; s++) {
284 const char *secname = secstrs + s->sh_name;
285
286 if (!(s->sh_flags & SHF_ALLOC))
287 continue;
288
289 if (strcmp(".ARM.exidx.init.text", secname) == 0)
290 maps[ARM_SEC_INIT].unw_sec = s;
291 else if (strcmp(".ARM.exidx.devinit.text", secname) == 0)
292 maps[ARM_SEC_DEVINIT].unw_sec = s;
293 else if (strcmp(".ARM.exidx", secname) == 0)
294 maps[ARM_SEC_CORE].unw_sec = s;
295 else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
296 maps[ARM_SEC_EXIT].unw_sec = s;
297 else if (strcmp(".ARM.exidx.devexit.text", secname) == 0)
298 maps[ARM_SEC_DEVEXIT].unw_sec = s;
299 else if (strcmp(".init.text", secname) == 0)
300 maps[ARM_SEC_INIT].txt_sec = s;
301 else if (strcmp(".devinit.text", secname) == 0)
302 maps[ARM_SEC_DEVINIT].txt_sec = s;
303 else if (strcmp(".text", secname) == 0)
304 maps[ARM_SEC_CORE].txt_sec = s;
305 else if (strcmp(".exit.text", secname) == 0)
306 maps[ARM_SEC_EXIT].txt_sec = s;
307 else if (strcmp(".devexit.text", secname) == 0)
308 maps[ARM_SEC_DEVEXIT].txt_sec = s;
309 }
310
311 for (i = 0; i < ARM_SEC_MAX; i++)
312 if (maps[i].unw_sec && maps[i].txt_sec)
313 mod->arch.unwind[i] =
314 unwind_table_add(maps[i].unw_sec->sh_addr,
315 maps[i].unw_sec->sh_size,
316 maps[i].txt_sec->sh_addr,
317 maps[i].txt_sec->sh_size);
318#endif
319#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
320 s = find_mod_section(hdr, sechdrs, ".pv_table");
321 if (s)
322 fixup_pv_table((void *)s->sh_addr, s->sh_size);
323#endif
324 s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
325 if (s && !is_smp())
326#ifdef CONFIG_SMP_ON_UP
327 fixup_smp((void *)s->sh_addr, s->sh_size);
328#else
329 return -EINVAL;
330#endif
331 return 0;
332}
333
334void
335module_arch_cleanup(struct module *mod)
336{
337#ifdef CONFIG_ARM_UNWIND
338 int i;
339
340 for (i = 0; i < ARM_SEC_MAX; i++)
341 if (mod->arch.unwind[i])
342 unwind_table_del(mod->arch.unwind[i]);
343#endif
344}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/kernel/module.c
4 *
5 * Copyright (C) 2002 Russell King.
6 * Modified for nommu by Hyok S. Choi
7 *
8 * Module allocation method suggested by Andi Kleen.
9 */
10#include <linux/module.h>
11#include <linux/moduleloader.h>
12#include <linux/kernel.h>
13#include <linux/mm.h>
14#include <linux/elf.h>
15#include <linux/vmalloc.h>
16#include <linux/fs.h>
17#include <linux/string.h>
18#include <linux/gfp.h>
19
20#include <asm/sections.h>
21#include <asm/smp_plat.h>
22#include <asm/unwind.h>
23#include <asm/opcodes.h>
24
25#ifdef CONFIG_XIP_KERNEL
26/*
27 * The XIP kernel text is mapped in the module area for modules and
28 * some other stuff to work without any indirect relocations.
29 * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
30 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
31 */
32#undef MODULES_VADDR
33#define MODULES_VADDR (((unsigned long)_exiprom + ~PMD_MASK) & PMD_MASK)
34#endif
35
36#ifdef CONFIG_MMU
37void *module_alloc(unsigned long size)
38{
39 gfp_t gfp_mask = GFP_KERNEL;
40 void *p;
41
42 /* Silence the initial allocation */
43 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS))
44 gfp_mask |= __GFP_NOWARN;
45
46 p = __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
47 gfp_mask, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
48 __builtin_return_address(0));
49 if (!IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || p)
50 return p;
51 return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
52 GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
53 __builtin_return_address(0));
54}
55#endif
56
57bool module_init_section(const char *name)
58{
59 return strstarts(name, ".init") ||
60 strstarts(name, ".ARM.extab.init") ||
61 strstarts(name, ".ARM.exidx.init");
62}
63
64bool module_exit_section(const char *name)
65{
66 return strstarts(name, ".exit") ||
67 strstarts(name, ".ARM.extab.exit") ||
68 strstarts(name, ".ARM.exidx.exit");
69}
70
71#ifdef CONFIG_ARM_HAS_GROUP_RELOCS
72/*
73 * This implements the partitioning algorithm for group relocations as
74 * documented in the ARM AArch32 ELF psABI (IHI 0044).
75 *
76 * A single PC-relative symbol reference is divided in up to 3 add or subtract
77 * operations, where the final one could be incorporated into a load/store
78 * instruction with immediate offset. E.g.,
79 *
80 * ADD Rd, PC, #... or ADD Rd, PC, #...
81 * ADD Rd, Rd, #... ADD Rd, Rd, #...
82 * LDR Rd, [Rd, #...] ADD Rd, Rd, #...
83 *
84 * The latter has a guaranteed range of only 16 MiB (3x8 == 24 bits), so it is
85 * of limited use in the kernel. However, the ADD/ADD/LDR combo has a range of
86 * -/+ 256 MiB, (2x8 + 12 == 28 bits), which means it has sufficient range for
87 * any in-kernel symbol reference (unless module PLTs are being used).
88 *
89 * The main advantage of this approach over the typical pattern using a literal
90 * load is that literal loads may miss in the D-cache, and generally lead to
91 * lower cache efficiency for variables that are referenced often from many
92 * different places in the code.
93 */
94static u32 get_group_rem(u32 group, u32 *offset)
95{
96 u32 val = *offset;
97 u32 shift;
98 do {
99 shift = val ? (31 - __fls(val)) & ~1 : 32;
100 *offset = val;
101 if (!val)
102 break;
103 val &= 0xffffff >> shift;
104 } while (group--);
105 return shift;
106}
107#endif
108
109int
110apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
111 unsigned int relindex, struct module *module)
112{
113 Elf32_Shdr *symsec = sechdrs + symindex;
114 Elf32_Shdr *relsec = sechdrs + relindex;
115 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
116 Elf32_Rel *rel = (void *)relsec->sh_addr;
117 unsigned int i;
118
119 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
120 unsigned long loc;
121 Elf32_Sym *sym;
122 const char *symname;
123#ifdef CONFIG_ARM_HAS_GROUP_RELOCS
124 u32 shift, group = 1;
125#endif
126 s32 offset;
127 u32 tmp;
128#ifdef CONFIG_THUMB2_KERNEL
129 u32 upper, lower, sign, j1, j2;
130#endif
131
132 offset = ELF32_R_SYM(rel->r_info);
133 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
134 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
135 module->name, relindex, i);
136 return -ENOEXEC;
137 }
138
139 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
140 symname = strtab + sym->st_name;
141
142 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
143 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
144 module->name, relindex, i, symname,
145 rel->r_offset, dstsec->sh_size);
146 return -ENOEXEC;
147 }
148
149 loc = dstsec->sh_addr + rel->r_offset;
150
151 switch (ELF32_R_TYPE(rel->r_info)) {
152 case R_ARM_NONE:
153 /* ignore */
154 break;
155
156 case R_ARM_ABS32:
157 case R_ARM_TARGET1:
158 *(u32 *)loc += sym->st_value;
159 break;
160
161 case R_ARM_PC24:
162 case R_ARM_CALL:
163 case R_ARM_JUMP24:
164 if (sym->st_value & 3) {
165 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (ARM -> Thumb)\n",
166 module->name, relindex, i, symname);
167 return -ENOEXEC;
168 }
169
170 offset = __mem_to_opcode_arm(*(u32 *)loc);
171 offset = (offset & 0x00ffffff) << 2;
172 if (offset & 0x02000000)
173 offset -= 0x04000000;
174
175 offset += sym->st_value - loc;
176
177 /*
178 * Route through a PLT entry if 'offset' exceeds the
179 * supported range. Note that 'offset + loc + 8'
180 * contains the absolute jump target, i.e.,
181 * @sym + addend, corrected for the +8 PC bias.
182 */
183 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&
184 (offset <= (s32)0xfe000000 ||
185 offset >= (s32)0x02000000))
186 offset = get_module_plt(module, loc,
187 offset + loc + 8)
188 - loc - 8;
189
190 if (offset <= (s32)0xfe000000 ||
191 offset >= (s32)0x02000000) {
192 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
193 module->name, relindex, i, symname,
194 ELF32_R_TYPE(rel->r_info), loc,
195 sym->st_value);
196 return -ENOEXEC;
197 }
198
199 offset >>= 2;
200 offset &= 0x00ffffff;
201
202 *(u32 *)loc &= __opcode_to_mem_arm(0xff000000);
203 *(u32 *)loc |= __opcode_to_mem_arm(offset);
204 break;
205
206 case R_ARM_V4BX:
207 /* Preserve Rm and the condition code. Alter
208 * other bits to re-code instruction as
209 * MOV PC,Rm.
210 */
211 *(u32 *)loc &= __opcode_to_mem_arm(0xf000000f);
212 *(u32 *)loc |= __opcode_to_mem_arm(0x01a0f000);
213 break;
214
215 case R_ARM_PREL31:
216 offset = (*(s32 *)loc << 1) >> 1; /* sign extend */
217 offset += sym->st_value - loc;
218 if (offset >= 0x40000000 || offset < -0x40000000) {
219 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
220 module->name, relindex, i, symname,
221 ELF32_R_TYPE(rel->r_info), loc,
222 sym->st_value);
223 return -ENOEXEC;
224 }
225 *(u32 *)loc &= 0x80000000;
226 *(u32 *)loc |= offset & 0x7fffffff;
227 break;
228
229 case R_ARM_REL32:
230 *(u32 *)loc += sym->st_value - loc;
231 break;
232
233 case R_ARM_MOVW_ABS_NC:
234 case R_ARM_MOVT_ABS:
235 case R_ARM_MOVW_PREL_NC:
236 case R_ARM_MOVT_PREL:
237 offset = tmp = __mem_to_opcode_arm(*(u32 *)loc);
238 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
239 offset = (offset ^ 0x8000) - 0x8000;
240
241 offset += sym->st_value;
242 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_PREL ||
243 ELF32_R_TYPE(rel->r_info) == R_ARM_MOVW_PREL_NC)
244 offset -= loc;
245 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS ||
246 ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_PREL)
247 offset >>= 16;
248
249 tmp &= 0xfff0f000;
250 tmp |= ((offset & 0xf000) << 4) |
251 (offset & 0x0fff);
252
253 *(u32 *)loc = __opcode_to_mem_arm(tmp);
254 break;
255
256#ifdef CONFIG_ARM_HAS_GROUP_RELOCS
257 case R_ARM_ALU_PC_G0_NC:
258 group = 0;
259 fallthrough;
260 case R_ARM_ALU_PC_G1_NC:
261 tmp = __mem_to_opcode_arm(*(u32 *)loc);
262 offset = ror32(tmp & 0xff, (tmp & 0xf00) >> 7);
263 if (tmp & BIT(22))
264 offset = -offset;
265 offset += sym->st_value - loc;
266 if (offset < 0) {
267 offset = -offset;
268 tmp = (tmp & ~BIT(23)) | BIT(22); // SUB opcode
269 } else {
270 tmp = (tmp & ~BIT(22)) | BIT(23); // ADD opcode
271 }
272
273 shift = get_group_rem(group, &offset);
274 if (shift < 24) {
275 offset >>= 24 - shift;
276 offset |= (shift + 8) << 7;
277 }
278 *(u32 *)loc = __opcode_to_mem_arm((tmp & ~0xfff) | offset);
279 break;
280
281 case R_ARM_LDR_PC_G2:
282 tmp = __mem_to_opcode_arm(*(u32 *)loc);
283 offset = tmp & 0xfff;
284 if (~tmp & BIT(23)) // U bit cleared?
285 offset = -offset;
286 offset += sym->st_value - loc;
287 if (offset < 0) {
288 offset = -offset;
289 tmp &= ~BIT(23); // clear U bit
290 } else {
291 tmp |= BIT(23); // set U bit
292 }
293 get_group_rem(2, &offset);
294
295 if (offset > 0xfff) {
296 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
297 module->name, relindex, i, symname,
298 ELF32_R_TYPE(rel->r_info), loc,
299 sym->st_value);
300 return -ENOEXEC;
301 }
302 *(u32 *)loc = __opcode_to_mem_arm((tmp & ~0xfff) | offset);
303 break;
304#endif
305#ifdef CONFIG_THUMB2_KERNEL
306 case R_ARM_THM_CALL:
307 case R_ARM_THM_JUMP24:
308 /*
309 * For function symbols, only Thumb addresses are
310 * allowed (no interworking).
311 *
312 * For non-function symbols, the destination
313 * has no specific ARM/Thumb disposition, so
314 * the branch is resolved under the assumption
315 * that interworking is not required.
316 */
317 if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
318 !(sym->st_value & 1)) {
319 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (Thumb -> ARM)\n",
320 module->name, relindex, i, symname);
321 return -ENOEXEC;
322 }
323
324 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
325 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
326
327 /*
328 * 25 bit signed address range (Thumb-2 BL and B.W
329 * instructions):
330 * S:I1:I2:imm10:imm11:0
331 * where:
332 * S = upper[10] = offset[24]
333 * I1 = ~(J1 ^ S) = offset[23]
334 * I2 = ~(J2 ^ S) = offset[22]
335 * imm10 = upper[9:0] = offset[21:12]
336 * imm11 = lower[10:0] = offset[11:1]
337 * J1 = lower[13]
338 * J2 = lower[11]
339 */
340 sign = (upper >> 10) & 1;
341 j1 = (lower >> 13) & 1;
342 j2 = (lower >> 11) & 1;
343 offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
344 ((~(j2 ^ sign) & 1) << 22) |
345 ((upper & 0x03ff) << 12) |
346 ((lower & 0x07ff) << 1);
347 if (offset & 0x01000000)
348 offset -= 0x02000000;
349 offset += sym->st_value - loc;
350
351 /*
352 * Route through a PLT entry if 'offset' exceeds the
353 * supported range.
354 */
355 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&
356 (offset <= (s32)0xff000000 ||
357 offset >= (s32)0x01000000))
358 offset = get_module_plt(module, loc,
359 offset + loc + 4)
360 - loc - 4;
361
362 if (offset <= (s32)0xff000000 ||
363 offset >= (s32)0x01000000) {
364 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
365 module->name, relindex, i, symname,
366 ELF32_R_TYPE(rel->r_info), loc,
367 sym->st_value);
368 return -ENOEXEC;
369 }
370
371 sign = (offset >> 24) & 1;
372 j1 = sign ^ (~(offset >> 23) & 1);
373 j2 = sign ^ (~(offset >> 22) & 1);
374 upper = (u16)((upper & 0xf800) | (sign << 10) |
375 ((offset >> 12) & 0x03ff));
376 lower = (u16)((lower & 0xd000) |
377 (j1 << 13) | (j2 << 11) |
378 ((offset >> 1) & 0x07ff));
379
380 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
381 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
382 break;
383
384 case R_ARM_THM_MOVW_ABS_NC:
385 case R_ARM_THM_MOVT_ABS:
386 case R_ARM_THM_MOVW_PREL_NC:
387 case R_ARM_THM_MOVT_PREL:
388 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
389 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
390
391 /*
392 * MOVT/MOVW instructions encoding in Thumb-2:
393 *
394 * i = upper[10]
395 * imm4 = upper[3:0]
396 * imm3 = lower[14:12]
397 * imm8 = lower[7:0]
398 *
399 * imm16 = imm4:i:imm3:imm8
400 */
401 offset = ((upper & 0x000f) << 12) |
402 ((upper & 0x0400) << 1) |
403 ((lower & 0x7000) >> 4) | (lower & 0x00ff);
404 offset = (offset ^ 0x8000) - 0x8000;
405 offset += sym->st_value;
406
407 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_PREL ||
408 ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVW_PREL_NC)
409 offset -= loc;
410 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS ||
411 ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_PREL)
412 offset >>= 16;
413
414 upper = (u16)((upper & 0xfbf0) |
415 ((offset & 0xf000) >> 12) |
416 ((offset & 0x0800) >> 1));
417 lower = (u16)((lower & 0x8f00) |
418 ((offset & 0x0700) << 4) |
419 (offset & 0x00ff));
420 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
421 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
422 break;
423#endif
424
425 default:
426 pr_err("%s: unknown relocation: %u\n",
427 module->name, ELF32_R_TYPE(rel->r_info));
428 return -ENOEXEC;
429 }
430 }
431 return 0;
432}
433
434struct mod_unwind_map {
435 const Elf_Shdr *unw_sec;
436 const Elf_Shdr *txt_sec;
437};
438
439static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
440 const Elf_Shdr *sechdrs, const char *name)
441{
442 const Elf_Shdr *s, *se;
443 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
444
445 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
446 if (strcmp(name, secstrs + s->sh_name) == 0)
447 return s;
448
449 return NULL;
450}
451
452extern void fixup_pv_table(const void *, unsigned long);
453extern void fixup_smp(const void *, unsigned long);
454
455int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
456 struct module *mod)
457{
458 const Elf_Shdr *s = NULL;
459#ifdef CONFIG_ARM_UNWIND
460 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
461 const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
462 struct list_head *unwind_list = &mod->arch.unwind_list;
463
464 INIT_LIST_HEAD(unwind_list);
465 mod->arch.init_table = NULL;
466
467 for (s = sechdrs; s < sechdrs_end; s++) {
468 const char *secname = secstrs + s->sh_name;
469 const char *txtname;
470 const Elf_Shdr *txt_sec;
471
472 if (!(s->sh_flags & SHF_ALLOC) ||
473 s->sh_type != ELF_SECTION_UNWIND)
474 continue;
475
476 if (!strcmp(".ARM.exidx", secname))
477 txtname = ".text";
478 else
479 txtname = secname + strlen(".ARM.exidx");
480 txt_sec = find_mod_section(hdr, sechdrs, txtname);
481
482 if (txt_sec) {
483 struct unwind_table *table =
484 unwind_table_add(s->sh_addr,
485 s->sh_size,
486 txt_sec->sh_addr,
487 txt_sec->sh_size);
488
489 list_add(&table->mod_list, unwind_list);
490
491 /* save init table for module_arch_freeing_init */
492 if (strcmp(".ARM.exidx.init.text", secname) == 0)
493 mod->arch.init_table = table;
494 }
495 }
496#endif
497#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
498 s = find_mod_section(hdr, sechdrs, ".pv_table");
499 if (s)
500 fixup_pv_table((void *)s->sh_addr, s->sh_size);
501#endif
502 s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
503 if (s && !is_smp())
504#ifdef CONFIG_SMP_ON_UP
505 fixup_smp((void *)s->sh_addr, s->sh_size);
506#else
507 return -EINVAL;
508#endif
509 return 0;
510}
511
512void
513module_arch_cleanup(struct module *mod)
514{
515#ifdef CONFIG_ARM_UNWIND
516 struct unwind_table *tmp;
517 struct unwind_table *n;
518
519 list_for_each_entry_safe(tmp, n,
520 &mod->arch.unwind_list, mod_list) {
521 list_del(&tmp->mod_list);
522 unwind_table_del(tmp);
523 }
524 mod->arch.init_table = NULL;
525#endif
526}
527
528void __weak module_arch_freeing_init(struct module *mod)
529{
530#ifdef CONFIG_ARM_UNWIND
531 struct unwind_table *init = mod->arch.init_table;
532
533 if (init) {
534 mod->arch.init_table = NULL;
535 list_del(&init->mod_list);
536 unwind_table_del(init);
537 }
538#endif
539}