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
16typedef unsigned long elf_greg_t;
17
18#define ELF_NGREG (sizeof(struct user_regs_struct) / sizeof(elf_greg_t))
19typedef elf_greg_t elf_gregset_t[ELF_NGREG];
20
21typedef 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
79extern unsigned int vdso64_enabled;
80#endif
81#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
82extern 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)	\
121do {						\
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
156static 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(&current->thread, _r, 0)
171
172#define	COMPAT_ELF_PLAT_INIT(regs, load_addr)		\
173	elf_common_init(&current->thread, regs, __USER_DS)
174
175void 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
179void 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)			\
192do {								\
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")
225extern void set_personality_64bit(void);
226extern 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
247extern 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
292struct task_struct;
293
294#define	ARCH_DLINFO_IA32						\
295do {									\
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 */
306static 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
313extern unsigned long task_size_32bit(void);
314extern unsigned long task_size_64bit(int full_addr_space);
315extern unsigned long get_mmap_base(int is_legacy);
316extern bool mmap_address_hint_valid(unsigned long addr, unsigned long len);
317extern 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							\
335do {									\
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							\
344do {									\
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						\
354if (exec->e_machine == EM_X86_64)					\
355	ARCH_DLINFO_X32;						\
356else 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
369struct linux_binprm;
370
371#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
372extern int arch_setup_additional_pages(struct linux_binprm *bprm,
373				       int uses_interp);
374extern 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
380extern bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs);
381
382/* Do not change the values. See get_align_mask() */
383enum align_flags {
384	ALIGN_VA_32	= BIT(0),
385	ALIGN_VA_64	= BIT(1),
386};
387
388struct va_alignment {
389	int flags;
390	unsigned long mask;
391	unsigned long bits;
392} ____cacheline_aligned;
393
394extern struct va_alignment va_align;
395#endif /* _ASM_X86_ELF_H */
396