arch/arm64/include/asm/elf.h

   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
 145 typedef 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
 151 typedef elf_greg_t elf_gregset_t[ELF_NGREG];
 152 typedef 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                                                     \
 169 do {                                                                    \
 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
 185 struct linux_binprm;
 186 extern 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 #ifdef CONFIG_COMPAT
 205
 206 /* PIE load location for compat arm. Must match ARM ELF_ET_DYN_BASE. */
 207 #define COMPAT_ELF_ET_DYN_BASE          0x000400000UL
 208
 209 /* AArch32 registers. */
 210 #define COMPAT_ELF_NGREG                18
 211 typedef unsigned int                    compat_elf_greg_t;
 212 typedef compat_elf_greg_t               compat_elf_gregset_t[COMPAT_ELF_NGREG];
 213
 214 /* AArch32 EABI. */
 215 #define EF_ARM_EABI_MASK                0xff000000
 216 #define compat_elf_check_arch(x)        (system_supports_32bit_el0() && \
 217                                          ((x)->e_machine == EM_ARM) && \
 218                                          ((x)->e_flags & EF_ARM_EABI_MASK))
 219
 220 #define compat_start_thread             compat_start_thread
 221 /*
 222  * Unlike the native SET_PERSONALITY macro, the compat version maintains
 223  * READ_IMPLIES_EXEC across an execve() since this is the behaviour on
 224  * arch/arm/.
 225  */
 226 #define COMPAT_SET_PERSONALITY(ex)                                      \
 227 ({                                                                      \
 228         set_thread_flag(TIF_32BIT);                                     \
 229  })
 230 #ifdef CONFIG_COMPAT_VDSO
 231 #define COMPAT_ARCH_DLINFO                                              \
 232 do {                                                                    \
 233         /*                                                              \
 234          * Note that we use Elf64_Off instead of elf_addr_t because     \
 235          * elf_addr_t in compat is defined as Elf32_Addr and casting    \
 236          * current->mm->context.vdso to it triggers a cast warning of   \
 237          * cast from pointer to integer of different size.              \
 238          */                                                             \
 239         NEW_AUX_ENT(AT_SYSINFO_EHDR,                                    \
 240                         (Elf64_Off)current->mm->context.vdso);          \
 241 } while (0)
 242 #else
 243 #define COMPAT_ARCH_DLINFO
 244 #endif
 245 extern int aarch32_setup_additional_pages(struct linux_binprm *bprm,
 246                                           int uses_interp);
 247 #define compat_arch_setup_additional_pages \
 248                                         aarch32_setup_additional_pages
 249
 250 #endif /* CONFIG_COMPAT */
 251
 252 struct arch_elf_state {
 253         int flags;
 254 };
 255
 256 #define ARM64_ELF_BTI           (1 << 0)
 257
 258 #define INIT_ARCH_ELF_STATE {                   \
 259         .flags = 0,                             \
 260 }
 261
 262 static inline int arch_parse_elf_property(u32 type, const void *data,
 263                                           size_t datasz, bool compat,
 264                                           struct arch_elf_state *arch)
 265 {
 266         /* No known properties for AArch32 yet */
 267         if (IS_ENABLED(CONFIG_COMPAT) && compat)
 268                 return 0;
 269
 270         if (type == GNU_PROPERTY_AARCH64_FEATURE_1_AND) {
 271                 const u32 *p = data;
 272
 273                 if (datasz != sizeof(*p))
 274                         return -ENOEXEC;
 275
 276                 if (system_supports_bti() &&
 277                     (*p & GNU_PROPERTY_AARCH64_FEATURE_1_BTI))
 278                         arch->flags |= ARM64_ELF_BTI;
 279         }
 280
 281         return 0;
 282 }
 283
 284 static inline int arch_elf_pt_proc(void *ehdr, void *phdr,
 285                                    struct file *f, bool is_interp,
 286                                    struct arch_elf_state *state)
 287 {
 288         return 0;
 289 }
 290
 291 static inline int arch_check_elf(void *ehdr, bool has_interp,
 292                                  void *interp_ehdr,
 293                                  struct arch_elf_state *state)
 294 {
 295         return 0;
 296 }
 297
 298 #endif /* !__ASSEMBLY__ */
 299
 300 #endif