1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_ELF_H
3 #define _ASM_X86_ELF_H
4
5 /*
6 * ELF register definitions..
7 */
8 #include <linux/thread_info.h>
9
10 #include <asm/ia32.h>
11 #include <asm/ptrace.h>
12 #include <asm/user.h>
13 #include <asm/auxvec.h>
14 #include <asm/fsgsbase.h>
15
16 typedef unsigned long elf_greg_t;
17
18 #define ELF_NGREG (sizeof(struct user_regs_struct) / sizeof(elf_greg_t))
19 typedef elf_greg_t elf_gregset_t[ELF_NGREG];
20
21 typedef struct user_i387_struct elf_fpregset_t;
22
23 #ifdef __i386__
24
25 #define R_386_NONE 0
26 #define R_386_32 1
27 #define R_386_PC32 2
28 #define R_386_GOT32 3
29 #define R_386_PLT32 4
30 #define R_386_COPY 5
31 #define R_386_GLOB_DAT 6
32 #define R_386_JMP_SLOT 7
33 #define R_386_RELATIVE 8
34 #define R_386_GOTOFF 9
35 #define R_386_GOTPC 10
36 #define R_386_NUM 11
37
38 /*
39 * These are used to set parameters in the core dumps.
40 */
41 #define ELF_CLASS ELFCLASS32
42 #define ELF_DATA ELFDATA2LSB
43 #define ELF_ARCH EM_386
44
45 #else
46
47 /* x86-64 relocation types */
48 #define R_X86_64_NONE 0 /* No reloc */
49 #define R_X86_64_64 1 /* Direct 64 bit */
50 #define R_X86_64_PC32 2 /* PC relative 32 bit signed */
51 #define R_X86_64_GOT32 3 /* 32 bit GOT entry */
52 #define R_X86_64_PLT32 4 /* 32 bit PLT address */
53 #define R_X86_64_COPY 5 /* Copy symbol at runtime */
54 #define R_X86_64_GLOB_DAT 6 /* Create GOT entry */
55 #define R_X86_64_JUMP_SLOT 7 /* Create PLT entry */
56 #define R_X86_64_RELATIVE 8 /* Adjust by program base */
57 #define R_X86_64_GOTPCREL 9 /* 32 bit signed pc relative
58 offset to GOT */
59 #define R_X86_64_32 10 /* Direct 32 bit zero extended */
60 #define R_X86_64_32S 11 /* Direct 32 bit sign extended */
61 #define R_X86_64_16 12 /* Direct 16 bit zero extended */
62 #define R_X86_64_PC16 13 /* 16 bit sign extended pc relative */
63 #define R_X86_64_8 14 /* Direct 8 bit sign extended */
64 #define R_X86_64_PC8 15 /* 8 bit sign extended pc relative */
65 #define R_X86_64_PC64 24 /* Place relative 64-bit signed */
66
67 /*
68 * These are used to set parameters in the core dumps.
69 */
70 #define ELF_CLASS ELFCLASS64
71 #define ELF_DATA ELFDATA2LSB
72 #define ELF_ARCH EM_X86_64
73
74 #endif
75
76 #include <asm/vdso.h>
77
78 #ifdef CONFIG_X86_64
79 extern unsigned int vdso64_enabled;
80 #endif
81 #if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
82 extern unsigned int vdso32_enabled;
83 #endif
84
85 /*
86 * This is used to ensure we don't load something for the wrong architecture.
87 */
88 #define elf_check_arch_ia32(x) \
89 (((x)->e_machine == EM_386) || ((x)->e_machine == EM_486))
90
91 #include <asm/processor.h>
92
93 #ifdef CONFIG_X86_32
94 #include <asm/desc.h>
95
96 #define elf_check_arch(x) elf_check_arch_ia32(x)
97
98 /* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program starts %edx
99 contains a pointer to a function which might be registered using `atexit'.
100 This provides a mean for the dynamic linker to call DT_FINI functions for
101 shared libraries that have been loaded before the code runs.
102
103 A value of 0 tells we have no such handler.
104
105 We might as well make sure everything else is cleared too (except for %esp),
106 just to make things more deterministic.
107 */
108 #define ELF_PLAT_INIT(_r, load_addr) \
109 do { \
110 _r->bx = 0; _r->cx = 0; _r->dx = 0; \
111 _r->si = 0; _r->di = 0; _r->bp = 0; \
112 _r->ax = 0; \
113 } while (0)
114
115 /*
116 * regs is struct pt_regs, pr_reg is elf_gregset_t (which is
117 * now struct_user_regs, they are different)
118 */
119
120 #define ELF_CORE_COPY_REGS(pr_reg, regs) \
121 do { \
122 pr_reg[0] = regs->bx; \
123 pr_reg[1] = regs->cx; \
124 pr_reg[2] = regs->dx; \
125 pr_reg[3] = regs->si; \
126 pr_reg[4] = regs->di; \
127 pr_reg[5] = regs->bp; \
128 pr_reg[6] = regs->ax; \
129 pr_reg[7] = regs->ds; \
130 pr_reg[8] = regs->es; \
131 pr_reg[9] = regs->fs; \
132 savesegment(gs, pr_reg[10]); \
133 pr_reg[11] = regs->orig_ax; \
134 pr_reg[12] = regs->ip; \
135 pr_reg[13] = regs->cs; \
136 pr_reg[14] = regs->flags; \
137 pr_reg[15] = regs->sp; \
138 pr_reg[16] = regs->ss; \
139 } while (0);
140
141 #define ELF_PLATFORM (utsname()->machine)
142 #define set_personality_64bit() do { } while (0)
143
144 #else /* CONFIG_X86_32 */
145
146 /*
147 * This is used to ensure we don't load something for the wrong architecture.
148 */
149 #define elf_check_arch(x) \
150 ((x)->e_machine == EM_X86_64)
151
152 #define compat_elf_check_arch(x) \
153 ((elf_check_arch_ia32(x) && ia32_enabled_verbose()) || \
154 (IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64))
155
elf_common_init(struct thread_struct * t,struct pt_regs * regs,const u16 ds)156 static inline void elf_common_init(struct thread_struct *t,
157 struct pt_regs *regs, const u16 ds)
158 {
159 /* ax gets execve's return value. */
160 /*regs->ax = */ regs->bx = regs->cx = regs->dx = 0;
161 regs->si = regs->di = regs->bp = 0;
162 regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0;
163 regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
164 t->fsbase = t->gsbase = 0;
165 t->fsindex = t->gsindex = 0;
166 t->ds = t->es = ds;
167 }
168
169 #define ELF_PLAT_INIT(_r, load_addr) \
170 elf_common_init(¤t->thread, _r, 0)
171
172 #define COMPAT_ELF_PLAT_INIT(regs, load_addr) \
173 elf_common_init(¤t->thread, regs, __USER_DS)
174
175 void compat_start_thread(struct pt_regs *regs, u32 new_ip, u32 new_sp, bool x32);
176 #define COMPAT_START_THREAD(ex, regs, new_ip, new_sp) \
177 compat_start_thread(regs, new_ip, new_sp, ex->e_machine == EM_X86_64)
178
179 void set_personality_ia32(bool);
180 #define COMPAT_SET_PERSONALITY(ex) \
181 set_personality_ia32((ex).e_machine == EM_X86_64)
182
183 #define COMPAT_ELF_PLATFORM ("i686")
184
185 /*
186 * regs is struct pt_regs, pr_reg is elf_gregset_t (which is
187 * now struct_user_regs, they are different). Assumes current is the process
188 * getting dumped.
189 */
190
191 #define ELF_CORE_COPY_REGS(pr_reg, regs) \
192 do { \
193 unsigned v; \
194 (pr_reg)[0] = (regs)->r15; \
195 (pr_reg)[1] = (regs)->r14; \
196 (pr_reg)[2] = (regs)->r13; \
197 (pr_reg)[3] = (regs)->r12; \
198 (pr_reg)[4] = (regs)->bp; \
199 (pr_reg)[5] = (regs)->bx; \
200 (pr_reg)[6] = (regs)->r11; \
201 (pr_reg)[7] = (regs)->r10; \
202 (pr_reg)[8] = (regs)->r9; \
203 (pr_reg)[9] = (regs)->r8; \
204 (pr_reg)[10] = (regs)->ax; \
205 (pr_reg)[11] = (regs)->cx; \
206 (pr_reg)[12] = (regs)->dx; \
207 (pr_reg)[13] = (regs)->si; \
208 (pr_reg)[14] = (regs)->di; \
209 (pr_reg)[15] = (regs)->orig_ax; \
210 (pr_reg)[16] = (regs)->ip; \
211 (pr_reg)[17] = (regs)->cs; \
212 (pr_reg)[18] = (regs)->flags; \
213 (pr_reg)[19] = (regs)->sp; \
214 (pr_reg)[20] = (regs)->ss; \
215 (pr_reg)[21] = x86_fsbase_read_cpu(); \
216 (pr_reg)[22] = x86_gsbase_read_cpu_inactive(); \
217 asm("movl %%ds,%0" : "=r" (v)); (pr_reg)[23] = v; \
218 asm("movl %%es,%0" : "=r" (v)); (pr_reg)[24] = v; \
219 asm("movl %%fs,%0" : "=r" (v)); (pr_reg)[25] = v; \
220 asm("movl %%gs,%0" : "=r" (v)); (pr_reg)[26] = v; \
221 } while (0);
222
223 /* I'm not sure if we can use '-' here */
224 #define ELF_PLATFORM ("x86_64")
225 extern void set_personality_64bit(void);
226 extern int force_personality32;
227
228 #endif /* !CONFIG_X86_32 */
229
230 #define CORE_DUMP_USE_REGSET
231 #define ELF_EXEC_PAGESIZE 4096
232
233 /*
234 * This is the base location for PIE (ET_DYN with INTERP) loads. On
235 * 64-bit, this is above 4GB to leave the entire 32-bit address
236 * space open for things that want to use the area for 32-bit pointers.
237 */
238 #define ELF_ET_DYN_BASE (mmap_is_ia32() ? 0x000400000UL : \
239 (DEFAULT_MAP_WINDOW / 3 * 2))
240
241 /* This yields a mask that user programs can use to figure out what
242 instruction set this CPU supports. This could be done in user space,
243 but it's not easy, and we've already done it here. */
244
245 #define ELF_HWCAP (boot_cpu_data.x86_capability[CPUID_1_EDX])
246
247 extern u32 elf_hwcap2;
248
249 /*
250 * HWCAP2 supplies mask with kernel enabled CPU features, so that
251 * the application can discover that it can safely use them.
252 * The bits are defined in uapi/asm/hwcap2.h.
253 */
254 #define ELF_HWCAP2 (elf_hwcap2)
255
256 /* This yields a string that ld.so will use to load implementation
257 specific libraries for optimization. This is more specific in
258 intent than poking at uname or /proc/cpuinfo.
259
260 For the moment, we have only optimizations for the Intel generations,
261 but that could change... */
262
263 #define SET_PERSONALITY(ex) set_personality_64bit()
264
265 /*
266 * An executable for which elf_read_implies_exec() returns TRUE will
267 * have the READ_IMPLIES_EXEC personality flag set automatically.
268 *
269 * The decision process for determining the results are:
270 *
271 * CPU: | lacks NX* | has NX, ia32 | has NX, x86_64 |
272 * ELF: | | | |
273 * ---------------------|------------|------------------|----------------|
274 * missing PT_GNU_STACK | exec-all | exec-all | exec-none |
275 * PT_GNU_STACK == RWX | exec-stack | exec-stack | exec-stack |
276 * PT_GNU_STACK == RW | exec-none | exec-none | exec-none |
277 *
278 * exec-all : all PROT_READ user mappings are executable, except when
279 * backed by files on a noexec-filesystem.
280 * exec-none : only PROT_EXEC user mappings are executable.
281 * exec-stack: only the stack and PROT_EXEC user mappings are executable.
282 *
283 * *this column has no architectural effect: NX markings are ignored by
284 * hardware, but may have behavioral effects when "wants X" collides with
285 * "cannot be X" constraints in memory permission flags, as in
286 * https://lkml.kernel.org/r/20190418055759.GA3155@mellanox.com
287 *
288 */
289 #define elf_read_implies_exec(ex, executable_stack) \
290 (mmap_is_ia32() && executable_stack == EXSTACK_DEFAULT)
291
292 struct task_struct;
293
294 #define ARCH_DLINFO_IA32 \
295 do { \
296 if (VDSO_CURRENT_BASE) { \
297 NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY); \
298 NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE); \
299 } \
300 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \
301 } while (0)
302
303 /*
304 * True on X86_32 or when emulating IA32 on X86_64
305 */
mmap_is_ia32(void)306 static inline int mmap_is_ia32(void)
307 {
308 return IS_ENABLED(CONFIG_X86_32) ||
309 (IS_ENABLED(CONFIG_COMPAT) &&
310 test_thread_flag(TIF_ADDR32));
311 }
312
313 extern unsigned long task_size_32bit(void);
314 extern unsigned long task_size_64bit(int full_addr_space);
315 extern unsigned long get_mmap_base(int is_legacy);
316 extern bool mmap_address_hint_valid(unsigned long addr, unsigned long len);
317 extern unsigned long get_sigframe_size(void);
318
319 #ifdef CONFIG_X86_32
320
321 #define __STACK_RND_MASK(is32bit) (0x7ff)
322 #define STACK_RND_MASK (0x7ff)
323
324 #define ARCH_DLINFO ARCH_DLINFO_IA32
325
326 /* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
327
328 #else /* CONFIG_X86_32 */
329
330 /* 1GB for 64bit, 8MB for 32bit */
331 #define __STACK_RND_MASK(is32bit) ((is32bit) ? 0x7ff : 0x3fffff)
332 #define STACK_RND_MASK __STACK_RND_MASK(mmap_is_ia32())
333
334 #define ARCH_DLINFO \
335 do { \
336 if (vdso64_enabled) \
337 NEW_AUX_ENT(AT_SYSINFO_EHDR, \
338 (unsigned long __force)current->mm->context.vdso); \
339 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \
340 } while (0)
341
342 /* As a historical oddity, the x32 and x86_64 vDSOs are controlled together. */
343 #define ARCH_DLINFO_X32 \
344 do { \
345 if (vdso64_enabled) \
346 NEW_AUX_ENT(AT_SYSINFO_EHDR, \
347 (unsigned long __force)current->mm->context.vdso); \
348 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \
349 } while (0)
350
351 #define AT_SYSINFO 32
352
353 #define COMPAT_ARCH_DLINFO \
354 if (exec->e_machine == EM_X86_64) \
355 ARCH_DLINFO_X32; \
356 else if (IS_ENABLED(CONFIG_IA32_EMULATION)) \
357 ARCH_DLINFO_IA32
358
359 #define COMPAT_ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000)
360
361 #endif /* !CONFIG_X86_32 */
362
363 #define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso)
364
365 #define VDSO_ENTRY \
366 ((unsigned long)current->mm->context.vdso + \
367 vdso_image_32.sym___kernel_vsyscall)
368
369 struct linux_binprm;
370
371 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
372 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
373 int uses_interp);
374 extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
375 int uses_interp, bool x32);
376 #define COMPAT_ARCH_SETUP_ADDITIONAL_PAGES(bprm, ex, interpreter) \
377 compat_arch_setup_additional_pages(bprm, interpreter, \
378 (ex->e_machine == EM_X86_64))
379
380 extern bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs);
381
382 /* Do not change the values. See get_align_mask() */
383 enum align_flags {
384 ALIGN_VA_32 = BIT(0),
385 ALIGN_VA_64 = BIT(1),
386 };
387
388 struct va_alignment {
389 int flags;
390 unsigned long mask;
391 unsigned long bits;
392 } ____cacheline_aligned;
393
394 extern struct va_alignment va_align;
395 #endif /* _ASM_X86_ELF_H */
396