xref: /linux/arch/x86/include/asm/elf.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 #ifndef _ASM_X86_ELF_H
2 #define _ASM_X86_ELF_H
3 
4 /*
5  * ELF register definitions..
6  */
7 #include <linux/thread_info.h>
8 
9 #include <asm/ptrace.h>
10 #include <asm/user.h>
11 #include <asm/auxvec.h>
12 
13 typedef unsigned long elf_greg_t;
14 
15 #define ELF_NGREG (sizeof(struct user_regs_struct) / sizeof(elf_greg_t))
16 typedef elf_greg_t elf_gregset_t[ELF_NGREG];
17 
18 typedef struct user_i387_struct elf_fpregset_t;
19 
20 #ifdef __i386__
21 
22 typedef struct user_fxsr_struct elf_fpxregset_t;
23 
24 #define R_386_NONE	0
25 #define R_386_32	1
26 #define R_386_PC32	2
27 #define R_386_GOT32	3
28 #define R_386_PLT32	4
29 #define R_386_COPY	5
30 #define R_386_GLOB_DAT	6
31 #define R_386_JMP_SLOT	7
32 #define R_386_RELATIVE	8
33 #define R_386_GOTOFF	9
34 #define R_386_GOTPC	10
35 #define R_386_NUM	11
36 
37 /*
38  * These are used to set parameters in the core dumps.
39  */
40 #define ELF_CLASS	ELFCLASS32
41 #define ELF_DATA	ELFDATA2LSB
42 #define ELF_ARCH	EM_386
43 
44 #else
45 
46 /* x86-64 relocation types */
47 #define R_X86_64_NONE		0	/* No reloc */
48 #define R_X86_64_64		1	/* Direct 64 bit  */
49 #define R_X86_64_PC32		2	/* PC relative 32 bit signed */
50 #define R_X86_64_GOT32		3	/* 32 bit GOT entry */
51 #define R_X86_64_PLT32		4	/* 32 bit PLT address */
52 #define R_X86_64_COPY		5	/* Copy symbol at runtime */
53 #define R_X86_64_GLOB_DAT	6	/* Create GOT entry */
54 #define R_X86_64_JUMP_SLOT	7	/* Create PLT entry */
55 #define R_X86_64_RELATIVE	8	/* Adjust by program base */
56 #define R_X86_64_GOTPCREL	9	/* 32 bit signed pc relative
57 					   offset to GOT */
58 #define R_X86_64_32		10	/* Direct 32 bit zero extended */
59 #define R_X86_64_32S		11	/* Direct 32 bit sign extended */
60 #define R_X86_64_16		12	/* Direct 16 bit zero extended */
61 #define R_X86_64_PC16		13	/* 16 bit sign extended pc relative */
62 #define R_X86_64_8		14	/* Direct 8 bit sign extended  */
63 #define R_X86_64_PC8		15	/* 8 bit sign extended pc relative */
64 
65 #define R_X86_64_NUM		16
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_COMMON(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 & 0xffff;		\
130 	pr_reg[8] = regs->es & 0xffff;		\
131 	pr_reg[9] = regs->fs & 0xffff;		\
132 	pr_reg[11] = regs->orig_ax;		\
133 	pr_reg[12] = regs->ip;			\
134 	pr_reg[13] = regs->cs & 0xffff;		\
135 	pr_reg[14] = regs->flags;		\
136 	pr_reg[15] = regs->sp;			\
137 	pr_reg[16] = regs->ss & 0xffff;		\
138 } while (0);
139 
140 #define ELF_CORE_COPY_REGS(pr_reg, regs)	\
141 do {						\
142 	ELF_CORE_COPY_REGS_COMMON(pr_reg, regs);\
143 	pr_reg[10] = get_user_gs(regs);		\
144 } while (0);
145 
146 #define ELF_CORE_COPY_KERNEL_REGS(pr_reg, regs)	\
147 do {						\
148 	ELF_CORE_COPY_REGS_COMMON(pr_reg, regs);\
149 	savesegment(gs, pr_reg[10]);		\
150 } while (0);
151 
152 #define ELF_PLATFORM	(utsname()->machine)
153 #define set_personality_64bit()	do { } while (0)
154 
155 #else /* CONFIG_X86_32 */
156 
157 /*
158  * This is used to ensure we don't load something for the wrong architecture.
159  */
160 #define elf_check_arch(x)			\
161 	((x)->e_machine == EM_X86_64)
162 
163 #define compat_elf_check_arch(x)					\
164 	(elf_check_arch_ia32(x) ||					\
165 	 (IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64))
166 
167 #if __USER32_DS != __USER_DS
168 # error "The following code assumes __USER32_DS == __USER_DS"
169 #endif
170 
171 static inline void elf_common_init(struct thread_struct *t,
172 				   struct pt_regs *regs, const u16 ds)
173 {
174 	/* Commented-out registers are cleared in stub_execve */
175 	/*regs->ax = regs->bx =*/ regs->cx = regs->dx = 0;
176 	regs->si = regs->di /*= regs->bp*/ = 0;
177 	regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0;
178 	/*regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;*/
179 	t->fs = t->gs = 0;
180 	t->fsindex = t->gsindex = 0;
181 	t->ds = t->es = ds;
182 }
183 
184 #define ELF_PLAT_INIT(_r, load_addr)			\
185 	elf_common_init(&current->thread, _r, 0)
186 
187 #define	COMPAT_ELF_PLAT_INIT(regs, load_addr)		\
188 	elf_common_init(&current->thread, regs, __USER_DS)
189 
190 void compat_start_thread(struct pt_regs *regs, u32 new_ip, u32 new_sp);
191 #define compat_start_thread compat_start_thread
192 
193 void set_personality_ia32(bool);
194 #define COMPAT_SET_PERSONALITY(ex)			\
195 	set_personality_ia32((ex).e_machine == EM_X86_64)
196 
197 #define COMPAT_ELF_PLATFORM			("i686")
198 
199 /*
200  * regs is struct pt_regs, pr_reg is elf_gregset_t (which is
201  * now struct_user_regs, they are different). Assumes current is the process
202  * getting dumped.
203  */
204 
205 #define ELF_CORE_COPY_REGS(pr_reg, regs)			\
206 do {								\
207 	unsigned v;						\
208 	(pr_reg)[0] = (regs)->r15;				\
209 	(pr_reg)[1] = (regs)->r14;				\
210 	(pr_reg)[2] = (regs)->r13;				\
211 	(pr_reg)[3] = (regs)->r12;				\
212 	(pr_reg)[4] = (regs)->bp;				\
213 	(pr_reg)[5] = (regs)->bx;				\
214 	(pr_reg)[6] = (regs)->r11;				\
215 	(pr_reg)[7] = (regs)->r10;				\
216 	(pr_reg)[8] = (regs)->r9;				\
217 	(pr_reg)[9] = (regs)->r8;				\
218 	(pr_reg)[10] = (regs)->ax;				\
219 	(pr_reg)[11] = (regs)->cx;				\
220 	(pr_reg)[12] = (regs)->dx;				\
221 	(pr_reg)[13] = (regs)->si;				\
222 	(pr_reg)[14] = (regs)->di;				\
223 	(pr_reg)[15] = (regs)->orig_ax;				\
224 	(pr_reg)[16] = (regs)->ip;				\
225 	(pr_reg)[17] = (regs)->cs;				\
226 	(pr_reg)[18] = (regs)->flags;				\
227 	(pr_reg)[19] = (regs)->sp;				\
228 	(pr_reg)[20] = (regs)->ss;				\
229 	(pr_reg)[21] = current->thread.fs;			\
230 	(pr_reg)[22] = current->thread.gs;			\
231 	asm("movl %%ds,%0" : "=r" (v)); (pr_reg)[23] = v;	\
232 	asm("movl %%es,%0" : "=r" (v)); (pr_reg)[24] = v;	\
233 	asm("movl %%fs,%0" : "=r" (v)); (pr_reg)[25] = v;	\
234 	asm("movl %%gs,%0" : "=r" (v)); (pr_reg)[26] = v;	\
235 } while (0);
236 
237 /* I'm not sure if we can use '-' here */
238 #define ELF_PLATFORM       ("x86_64")
239 extern void set_personality_64bit(void);
240 extern unsigned int sysctl_vsyscall32;
241 extern int force_personality32;
242 
243 #endif /* !CONFIG_X86_32 */
244 
245 #define CORE_DUMP_USE_REGSET
246 #define ELF_EXEC_PAGESIZE	4096
247 
248 /* This is the location that an ET_DYN program is loaded if exec'ed.  Typical
249    use of this is to invoke "./ld.so someprog" to test out a new version of
250    the loader.  We need to make sure that it is out of the way of the program
251    that it will "exec", and that there is sufficient room for the brk.  */
252 
253 #define ELF_ET_DYN_BASE		(TASK_SIZE / 3 * 2)
254 
255 /* This yields a mask that user programs can use to figure out what
256    instruction set this CPU supports.  This could be done in user space,
257    but it's not easy, and we've already done it here.  */
258 
259 #define ELF_HWCAP		(boot_cpu_data.x86_capability[0])
260 
261 /* This yields a string that ld.so will use to load implementation
262    specific libraries for optimization.  This is more specific in
263    intent than poking at uname or /proc/cpuinfo.
264 
265    For the moment, we have only optimizations for the Intel generations,
266    but that could change... */
267 
268 #define SET_PERSONALITY(ex) set_personality_64bit()
269 
270 /*
271  * An executable for which elf_read_implies_exec() returns TRUE will
272  * have the READ_IMPLIES_EXEC personality flag set automatically.
273  */
274 #define elf_read_implies_exec(ex, executable_stack)	\
275 	(executable_stack != EXSTACK_DISABLE_X)
276 
277 struct task_struct;
278 
279 #define	ARCH_DLINFO_IA32						\
280 do {									\
281 	if (vdso32_enabled) {						\
282 		NEW_AUX_ENT(AT_SYSINFO,	VDSO_ENTRY);			\
283 		NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE);	\
284 	}								\
285 } while (0)
286 
287 #ifdef CONFIG_X86_32
288 
289 #define STACK_RND_MASK (0x7ff)
290 
291 #define ARCH_DLINFO		ARCH_DLINFO_IA32
292 
293 /* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
294 
295 #else /* CONFIG_X86_32 */
296 
297 /* 1GB for 64bit, 8MB for 32bit */
298 #define STACK_RND_MASK (test_thread_flag(TIF_ADDR32) ? 0x7ff : 0x3fffff)
299 
300 #define ARCH_DLINFO							\
301 do {									\
302 	if (vdso64_enabled)						\
303 		NEW_AUX_ENT(AT_SYSINFO_EHDR,				\
304 			    (unsigned long __force)current->mm->context.vdso); \
305 } while (0)
306 
307 /* As a historical oddity, the x32 and x86_64 vDSOs are controlled together. */
308 #define ARCH_DLINFO_X32							\
309 do {									\
310 	if (vdso64_enabled)						\
311 		NEW_AUX_ENT(AT_SYSINFO_EHDR,				\
312 			    (unsigned long __force)current->mm->context.vdso); \
313 } while (0)
314 
315 #define AT_SYSINFO		32
316 
317 #define COMPAT_ARCH_DLINFO						\
318 if (test_thread_flag(TIF_X32))						\
319 	ARCH_DLINFO_X32;						\
320 else									\
321 	ARCH_DLINFO_IA32
322 
323 #define COMPAT_ELF_ET_DYN_BASE	(TASK_UNMAPPED_BASE + 0x1000000)
324 
325 #endif /* !CONFIG_X86_32 */
326 
327 #define VDSO_CURRENT_BASE	((unsigned long)current->mm->context.vdso)
328 
329 #define VDSO_ENTRY							\
330 	((unsigned long)current->mm->context.vdso +			\
331 	 selected_vdso32->sym___kernel_vsyscall)
332 
333 struct linux_binprm;
334 
335 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
336 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
337 				       int uses_interp);
338 extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
339 					      int uses_interp);
340 #define compat_arch_setup_additional_pages compat_arch_setup_additional_pages
341 
342 /*
343  * True on X86_32 or when emulating IA32 on X86_64
344  */
345 static inline int mmap_is_ia32(void)
346 {
347 	return config_enabled(CONFIG_X86_32) ||
348 	       (config_enabled(CONFIG_COMPAT) &&
349 		test_thread_flag(TIF_ADDR32));
350 }
351 
352 /* Do not change the values. See get_align_mask() */
353 enum align_flags {
354 	ALIGN_VA_32	= BIT(0),
355 	ALIGN_VA_64	= BIT(1),
356 };
357 
358 struct va_alignment {
359 	int flags;
360 	unsigned long mask;
361 	unsigned long bits;
362 } ____cacheline_aligned;
363 
364 extern struct va_alignment va_align;
365 extern unsigned long align_vdso_addr(unsigned long);
366 #endif /* _ASM_X86_ELF_H */
367