1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2012 ARM Ltd.
4 */
5#ifndef __ASM_ELF_H
6#define __ASM_ELF_H
7
8#include <asm/hwcap.h>
9
10/*
11 * ELF register definitions..
12 */
13#include <asm/ptrace.h>
14#include <asm/user.h>
15
16/*
17 * AArch64 static relocation types.
18 */
19
20/* Miscellaneous. */
21#define R_ARM_NONE			0
22#define R_AARCH64_NONE			256
23
24/* Data. */
25#define R_AARCH64_ABS64			257
26#define R_AARCH64_ABS32			258
27#define R_AARCH64_ABS16			259
28#define R_AARCH64_PREL64		260
29#define R_AARCH64_PREL32		261
30#define R_AARCH64_PREL16		262
31
32/* Instructions. */
33#define R_AARCH64_MOVW_UABS_G0		263
34#define R_AARCH64_MOVW_UABS_G0_NC	264
35#define R_AARCH64_MOVW_UABS_G1		265
36#define R_AARCH64_MOVW_UABS_G1_NC	266
37#define R_AARCH64_MOVW_UABS_G2		267
38#define R_AARCH64_MOVW_UABS_G2_NC	268
39#define R_AARCH64_MOVW_UABS_G3		269
40
41#define R_AARCH64_MOVW_SABS_G0		270
42#define R_AARCH64_MOVW_SABS_G1		271
43#define R_AARCH64_MOVW_SABS_G2		272
44
45#define R_AARCH64_LD_PREL_LO19		273
46#define R_AARCH64_ADR_PREL_LO21		274
47#define R_AARCH64_ADR_PREL_PG_HI21	275
48#define R_AARCH64_ADR_PREL_PG_HI21_NC	276
49#define R_AARCH64_ADD_ABS_LO12_NC	277
50#define R_AARCH64_LDST8_ABS_LO12_NC	278
51
52#define R_AARCH64_TSTBR14		279
53#define R_AARCH64_CONDBR19		280
54#define R_AARCH64_JUMP26		282
55#define R_AARCH64_CALL26		283
56#define R_AARCH64_LDST16_ABS_LO12_NC	284
57#define R_AARCH64_LDST32_ABS_LO12_NC	285
58#define R_AARCH64_LDST64_ABS_LO12_NC	286
59#define R_AARCH64_LDST128_ABS_LO12_NC	299
60
61#define R_AARCH64_MOVW_PREL_G0		287
62#define R_AARCH64_MOVW_PREL_G0_NC	288
63#define R_AARCH64_MOVW_PREL_G1		289
64#define R_AARCH64_MOVW_PREL_G1_NC	290
65#define R_AARCH64_MOVW_PREL_G2		291
66#define R_AARCH64_MOVW_PREL_G2_NC	292
67#define R_AARCH64_MOVW_PREL_G3		293
68
69#define R_AARCH64_RELATIVE		1027
70
71/*
72 * These are used to set parameters in the core dumps.
73 */
74#define ELF_CLASS	ELFCLASS64
75#ifdef __AARCH64EB__
76#define ELF_DATA	ELFDATA2MSB
77#else
78#define ELF_DATA	ELFDATA2LSB
79#endif
80#define ELF_ARCH	EM_AARCH64
81
82/*
83 * This yields a string that ld.so will use to load implementation
84 * specific libraries for optimization.  This is more specific in
85 * intent than poking at uname or /proc/cpuinfo.
86 */
87#define ELF_PLATFORM_SIZE	16
88#ifdef __AARCH64EB__
89#define ELF_PLATFORM		("aarch64_be")
90#else
91#define ELF_PLATFORM		("aarch64")
92#endif
93
94/*
95 * This is used to ensure we don't load something for the wrong architecture.
96 */
97#define elf_check_arch(x)		((x)->e_machine == EM_AARCH64)
98
99/*
100 * An executable for which elf_read_implies_exec() returns TRUE will
101 * have the READ_IMPLIES_EXEC personality flag set automatically.
102 *
103 * The decision process for determining the results are:
104 *
105 * �� �� �� �� �� ��   ��CPU*: | arm32�� ��   | arm64      |
106 * ELF: �� �� ��    �� �� �� ��| �� �� �� �� �� ��| �� �� �� �� �� ��|
107 * ---------------------|------------|------------|
108 * missing PT_GNU_STACK | exec-all �� | exec-none�� |
109 * PT_GNU_STACK == RWX ��| exec-stack | exec-stack |
110 * PT_GNU_STACK == RW �� | exec-none  | exec-none  |
111 *
112 *  exec-all  : all PROT_READ user mappings are executable, except when
113 *              backed by files on a noexec-filesystem.
114 *  exec-none : only PROT_EXEC user mappings are executable.
115 *  exec-stack: only the stack and PROT_EXEC user mappings are executable.
116 *
117 *  *all arm64 CPUs support NX, so there is no "lacks NX" column.
118 *
119 */
120#define compat_elf_read_implies_exec(ex, stk)	(stk == EXSTACK_DEFAULT)
121
122#define CORE_DUMP_USE_REGSET
123#define ELF_EXEC_PAGESIZE	PAGE_SIZE
124
125/*
126 * This is the base location for PIE (ET_DYN with INTERP) loads. On
127 * 64-bit, this is above 4GB to leave the entire 32-bit address
128 * space open for things that want to use the area for 32-bit pointers.
129 */
130#ifdef CONFIG_ARM64_FORCE_52BIT
131#define ELF_ET_DYN_BASE		(2 * TASK_SIZE_64 / 3)
132#else
133#define ELF_ET_DYN_BASE		(2 * DEFAULT_MAP_WINDOW_64 / 3)
134#endif /* CONFIG_ARM64_FORCE_52BIT */
135
136#ifndef __ASSEMBLY__
137
138#include <uapi/linux/elf.h>
139#include <linux/bug.h>
140#include <linux/errno.h>
141#include <linux/fs.h>
142#include <linux/types.h>
143#include <asm/processor.h> /* for signal_minsigstksz, used by ARCH_DLINFO */
144
145typedef unsigned long elf_greg_t;
146
147#define ELF_NGREG (sizeof(struct user_pt_regs) / sizeof(elf_greg_t))
148#define ELF_CORE_COPY_REGS(dest, regs)	\
149	*(struct user_pt_regs *)&(dest) = (regs)->user_regs;
150
151typedef elf_greg_t elf_gregset_t[ELF_NGREG];
152typedef struct user_fpsimd_state elf_fpregset_t;
153
154/*
155 * When the program starts, a1 contains a pointer to a function to be
156 * registered with atexit, as per the SVR4 ABI.  A value of 0 means we have no
157 * such handler.
158 */
159#define ELF_PLAT_INIT(_r, load_addr)	(_r)->regs[0] = 0
160
161#define SET_PERSONALITY(ex)						\
162({									\
163	clear_thread_flag(TIF_32BIT);					\
164	current->personality &= ~READ_IMPLIES_EXEC;			\
165})
166
167/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
168#define ARCH_DLINFO							\
169do {									\
170	NEW_AUX_ENT(AT_SYSINFO_EHDR,					\
171		    (elf_addr_t)current->mm->context.vdso);		\
172									\
173	/*								\
174	 * Should always be nonzero unless there's a kernel bug.	\
175	 * If we haven't determined a sensible value to give to		\
176	 * userspace, omit the entry:					\
177	 */								\
178	if (likely(signal_minsigstksz))					\
179		NEW_AUX_ENT(AT_MINSIGSTKSZ, signal_minsigstksz);	\
180	else								\
181		NEW_AUX_ENT(AT_IGNORE, 0);				\
182} while (0)
183
184#define ARCH_HAS_SETUP_ADDITIONAL_PAGES
185struct linux_binprm;
186extern int arch_setup_additional_pages(struct linux_binprm *bprm,
187				       int uses_interp);
188
189/* 1GB of VA */
190#ifdef CONFIG_COMPAT
191#define STACK_RND_MASK			(test_thread_flag(TIF_32BIT) ? \
192						0x7ff >> (PAGE_SHIFT - 12) : \
193						0x3ffff >> (PAGE_SHIFT - 12))
194#else
195#define STACK_RND_MASK			(0x3ffff >> (PAGE_SHIFT - 12))
196#endif
197
198#ifdef __AARCH64EB__
199#define COMPAT_ELF_PLATFORM		("v8b")
200#else
201#define COMPAT_ELF_PLATFORM		("v8l")
202#endif
203
204/* AArch32 registers. */
205#define COMPAT_ELF_NGREG		18
206typedef unsigned int			compat_elf_greg_t;
207typedef compat_elf_greg_t		compat_elf_gregset_t[COMPAT_ELF_NGREG];
208
209#ifdef CONFIG_COMPAT
210
211/* PIE load location for compat arm. Must match ARM ELF_ET_DYN_BASE. */
212#define COMPAT_ELF_ET_DYN_BASE		0x000400000UL
213
214/* AArch32 EABI. */
215#define EF_ARM_EABI_MASK		0xff000000
216int compat_elf_check_arch(const struct elf32_hdr *);
217#define compat_elf_check_arch		compat_elf_check_arch
218#define compat_start_thread		compat_start_thread
219/*
220 * Unlike the native SET_PERSONALITY macro, the compat version maintains
221 * READ_IMPLIES_EXEC across an execve() since this is the behaviour on
222 * arch/arm/.
223 */
224#define COMPAT_SET_PERSONALITY(ex)					\
225({									\
226	set_thread_flag(TIF_32BIT);					\
227 })
228#ifdef CONFIG_COMPAT_VDSO
229#define COMPAT_ARCH_DLINFO						\
230do {									\
231	/*								\
232	 * Note that we use Elf64_Off instead of elf_addr_t because	\
233	 * elf_addr_t in compat is defined as Elf32_Addr and casting	\
234	 * current->mm->context.vdso to it triggers a cast warning of	\
235	 * cast from pointer to integer of different size.		\
236	 */								\
237	NEW_AUX_ENT(AT_SYSINFO_EHDR,					\
238			(Elf64_Off)current->mm->context.vdso);		\
239} while (0)
240#else
241#define COMPAT_ARCH_DLINFO
242#endif
243extern int aarch32_setup_additional_pages(struct linux_binprm *bprm,
244					  int uses_interp);
245#define compat_arch_setup_additional_pages \
246					aarch32_setup_additional_pages
247
248#endif /* CONFIG_COMPAT */
249
250struct arch_elf_state {
251	int flags;
252};
253
254#define ARM64_ELF_BTI		(1 << 0)
255
256#define INIT_ARCH_ELF_STATE {			\
257	.flags = 0,				\
258}
259
260static inline int arch_parse_elf_property(u32 type, const void *data,
261					  size_t datasz, bool compat,
262					  struct arch_elf_state *arch)
263{
264	/* No known properties for AArch32 yet */
265	if (IS_ENABLED(CONFIG_COMPAT) && compat)
266		return 0;
267
268	if (type == GNU_PROPERTY_AARCH64_FEATURE_1_AND) {
269		const u32 *p = data;
270
271		if (datasz != sizeof(*p))
272			return -ENOEXEC;
273
274		if (system_supports_bti() &&
275		    (*p & GNU_PROPERTY_AARCH64_FEATURE_1_BTI))
276			arch->flags |= ARM64_ELF_BTI;
277	}
278
279	return 0;
280}
281
282static inline int arch_elf_pt_proc(void *ehdr, void *phdr,
283				   struct file *f, bool is_interp,
284				   struct arch_elf_state *state)
285{
286	return 0;
287}
288
289static inline int arch_check_elf(void *ehdr, bool has_interp,
290				 void *interp_ehdr,
291				 struct arch_elf_state *state)
292{
293	return 0;
294}
295
296#endif /* !__ASSEMBLY__ */
297
298#endif
299