arch/x86/include/asm/elf.h

   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/ptrace.h>
  11 #include <asm/user.h>
  12 #include <asm/auxvec.h>
  13 #include <asm/fsgsbase.h>
  14
  15 typedef unsigned long elf_greg_t;
  16
  17 #define ELF_NGREG (sizeof(struct user_regs_struct) / sizeof(elf_greg_t))
  18 typedef elf_greg_t elf_gregset_t[ELF_NGREG];
  19
  20 typedef struct user_i387_struct elf_fpregset_t;
  21
  22 #ifdef __i386__
  23
  24 typedef struct user_fxsr_struct elf_fpxregset_t;
  25
  26 #define R_386_NONE      0
  27 #define R_386_32        1
  28 #define R_386_PC32      2
  29 #define R_386_GOT32     3
  30 #define R_386_PLT32     4
  31 #define R_386_COPY      5
  32 #define R_386_GLOB_DAT  6
  33 #define R_386_JMP_SLOT  7
  34 #define R_386_RELATIVE  8
  35 #define R_386_GOTOFF    9
  36 #define R_386_GOTPC     10
  37 #define R_386_NUM       11
  38
  39 /*
  40  * These are used to set parameters in the core dumps.
  41  */
  42 #define ELF_CLASS       ELFCLASS32
  43 #define ELF_DATA        ELFDATA2LSB
  44 #define ELF_ARCH        EM_386
  45
  46 #else
  47
  48 /* x86-64 relocation types */
  49 #define R_X86_64_NONE           0       /* No reloc */
  50 #define R_X86_64_64             1       /* Direct 64 bit  */
  51 #define R_X86_64_PC32           2       /* PC relative 32 bit signed */
  52 #define R_X86_64_GOT32          3       /* 32 bit GOT entry */
  53 #define R_X86_64_PLT32          4       /* 32 bit PLT address */
  54 #define R_X86_64_COPY           5       /* Copy symbol at runtime */
  55 #define R_X86_64_GLOB_DAT       6       /* Create GOT entry */
  56 #define R_X86_64_JUMP_SLOT      7       /* Create PLT entry */
  57 #define R_X86_64_RELATIVE       8       /* Adjust by program base */
  58 #define R_X86_64_GOTPCREL       9       /* 32 bit signed pc relative
  59                                            offset to GOT */
  60 #define R_X86_64_32             10      /* Direct 32 bit zero extended */
  61 #define R_X86_64_32S            11      /* Direct 32 bit sign extended */
  62 #define R_X86_64_16             12      /* Direct 16 bit zero extended */
  63 #define R_X86_64_PC16           13      /* 16 bit sign extended pc relative */
  64 #define R_X86_64_8              14      /* Direct 8 bit sign extended  */
  65 #define R_X86_64_PC8            15      /* 8 bit sign extended pc relative */
  66 #define R_X86_64_PC64           24      /* Place relative 64-bit signed */
  67
  68 /*
  69  * These are used to set parameters in the core dumps.
  70  */
  71 #define ELF_CLASS       ELFCLASS64
  72 #define ELF_DATA        ELFDATA2LSB
  73 #define ELF_ARCH        EM_X86_64
  74
  75 #endif
  76
  77 #include <asm/vdso.h>
  78
  79 #ifdef CONFIG_X86_64
  80 extern unsigned int vdso64_enabled;
  81 #endif
  82 #if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
  83 extern unsigned int vdso32_enabled;
  84 #endif
  85
  86 /*
  87  * This is used to ensure we don't load something for the wrong architecture.
  88  */
  89 #define elf_check_arch_ia32(x) \
  90         (((x)->e_machine == EM_386) || ((x)->e_machine == EM_486))
  91
  92 #include <asm/processor.h>
  93
  94 #ifdef CONFIG_X86_32
  95 #include <asm/desc.h>
  96
  97 #define elf_check_arch(x)       elf_check_arch_ia32(x)
  98
  99 /* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program starts %edx
 100    contains a pointer to a function which might be registered using `atexit'.
 101    This provides a mean for the dynamic linker to call DT_FINI functions for
 102    shared libraries that have been loaded before the code runs.
 103
 104    A value of 0 tells we have no such handler.
 105
 106    We might as well make sure everything else is cleared too (except for %esp),
 107    just to make things more deterministic.
 108  */
 109 #define ELF_PLAT_INIT(_r, load_addr)            \
 110         do {                                    \
 111         _r->bx = 0; _r->cx = 0; _r->dx = 0;     \
 112         _r->si = 0; _r->di = 0; _r->bp = 0;     \
 113         _r->ax = 0;                             \
 114 } while (0)
 115
 116 /*
 117  * regs is struct pt_regs, pr_reg is elf_gregset_t (which is
 118  * now struct_user_regs, they are different)
 119  */
 120
 121 #define ELF_CORE_COPY_REGS_COMMON(pr_reg, regs) \
 122 do {                                            \
 123         pr_reg[0] = regs->bx;                   \
 124         pr_reg[1] = regs->cx;                   \
 125         pr_reg[2] = regs->dx;                   \
 126         pr_reg[3] = regs->si;                   \
 127         pr_reg[4] = regs->di;                   \
 128         pr_reg[5] = regs->bp;                   \
 129         pr_reg[6] = regs->ax;                   \
 130         pr_reg[7] = regs->ds;                   \
 131         pr_reg[8] = regs->es;                   \
 132         pr_reg[9] = regs->fs;                   \
 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_CORE_COPY_REGS(pr_reg, regs)        \
 142 do {                                            \
 143         ELF_CORE_COPY_REGS_COMMON(pr_reg, regs);\
 144         pr_reg[10] = get_user_gs(regs);         \
 145 } while (0);
 146
 147 #define ELF_CORE_COPY_KERNEL_REGS(pr_reg, regs) \
 148 do {                                            \
 149         ELF_CORE_COPY_REGS_COMMON(pr_reg, regs);\
 150         savesegment(gs, pr_reg[10]);            \
 151 } while (0);
 152
 153 #define ELF_PLATFORM    (utsname()->machine)
 154 #define set_personality_64bit() do { } while (0)
 155
 156 #else /* CONFIG_X86_32 */
 157
 158 /*
 159  * This is used to ensure we don't load something for the wrong architecture.
 160  */
 161 #define elf_check_arch(x)                       \
 162         ((x)->e_machine == EM_X86_64)
 163
 164 #define compat_elf_check_arch(x)                                        \
 165         (elf_check_arch_ia32(x) ||                                      \
 166          (IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64))
 167
 168 #if __USER32_DS != __USER_DS
 169 # error "The following code assumes __USER32_DS == __USER_DS"
 170 #endif
 171
 172 static inline void elf_common_init(struct thread_struct *t,
 173                                    struct pt_regs *regs, const u16 ds)
 174 {
 175         /* ax gets execve's return value. */
 176         /*regs->ax = */ regs->bx = regs->cx = regs->dx = 0;
 177         regs->si = regs->di = regs->bp = 0;
 178         regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0;
 179         regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
 180         t->fsbase = t->gsbase = 0;
 181         t->fsindex = t->gsindex = 0;
 182         t->ds = t->es = ds;
 183 }
 184
 185 #define ELF_PLAT_INIT(_r, load_addr)                    \
 186         elf_common_init(&current->thread, _r, 0)
 187
 188 #define COMPAT_ELF_PLAT_INIT(regs, load_addr)           \
 189         elf_common_init(&current->thread, regs, __USER_DS)
 190
 191 void compat_start_thread(struct pt_regs *regs, u32 new_ip, u32 new_sp);
 192 #define compat_start_thread compat_start_thread
 193
 194 void set_personality_ia32(bool);
 195 #define COMPAT_SET_PERSONALITY(ex)                      \
 196         set_personality_ia32((ex).e_machine == EM_X86_64)
 197
 198 #define COMPAT_ELF_PLATFORM                     ("i686")
 199
 200 /*
 201  * regs is struct pt_regs, pr_reg is elf_gregset_t (which is
 202  * now struct_user_regs, they are different). Assumes current is the process
 203  * getting dumped.
 204  */
 205
 206 #define ELF_CORE_COPY_REGS(pr_reg, regs)                        \
 207 do {                                                            \
 208         unsigned v;                                             \
 209         (pr_reg)[0] = (regs)->r15;                              \
 210         (pr_reg)[1] = (regs)->r14;                              \
 211         (pr_reg)[2] = (regs)->r13;                              \
 212         (pr_reg)[3] = (regs)->r12;                              \
 213         (pr_reg)[4] = (regs)->bp;                               \
 214         (pr_reg)[5] = (regs)->bx;                               \
 215         (pr_reg)[6] = (regs)->r11;                              \
 216         (pr_reg)[7] = (regs)->r10;                              \
 217         (pr_reg)[8] = (regs)->r9;                               \
 218         (pr_reg)[9] = (regs)->r8;                               \
 219         (pr_reg)[10] = (regs)->ax;                              \
 220         (pr_reg)[11] = (regs)->cx;                              \
 221         (pr_reg)[12] = (regs)->dx;                              \
 222         (pr_reg)[13] = (regs)->si;                              \
 223         (pr_reg)[14] = (regs)->di;                              \
 224         (pr_reg)[15] = (regs)->orig_ax;                         \
 225         (pr_reg)[16] = (regs)->ip;                              \
 226         (pr_reg)[17] = (regs)->cs;                              \
 227         (pr_reg)[18] = (regs)->flags;                           \
 228         (pr_reg)[19] = (regs)->sp;                              \
 229         (pr_reg)[20] = (regs)->ss;                              \
 230         (pr_reg)[21] = x86_fsbase_read_cpu();                   \
 231         (pr_reg)[22] = x86_gsbase_read_cpu_inactive();          \
 232         asm("movl %%ds,%0" : "=r" (v)); (pr_reg)[23] = v;       \
 233         asm("movl %%es,%0" : "=r" (v)); (pr_reg)[24] = v;       \
 234         asm("movl %%fs,%0" : "=r" (v)); (pr_reg)[25] = v;       \
 235         asm("movl %%gs,%0" : "=r" (v)); (pr_reg)[26] = v;       \
 236 } while (0);
 237
 238 /* I'm not sure if we can use '-' here */
 239 #define ELF_PLATFORM       ("x86_64")
 240 extern void set_personality_64bit(void);
 241 extern unsigned int sysctl_vsyscall32;
 242 extern int force_personality32;
 243
 244 #endif /* !CONFIG_X86_32 */
 245
 246 #define CORE_DUMP_USE_REGSET
 247 #define ELF_EXEC_PAGESIZE       4096
 248
 249 /*
 250  * This is the base location for PIE (ET_DYN with INTERP) loads. On
 251  * 64-bit, this is above 4GB to leave the entire 32-bit address
 252  * space open for things that want to use the area for 32-bit pointers.
 253  */
 254 #define ELF_ET_DYN_BASE         (mmap_is_ia32() ? 0x000400000UL : \
 255                                                   (DEFAULT_MAP_WINDOW / 3 * 2))
 256
 257 /* This yields a mask that user programs can use to figure out what
 258    instruction set this CPU supports.  This could be done in user space,
 259    but it's not easy, and we've already done it here.  */
 260
 261 #define ELF_HWCAP               (boot_cpu_data.x86_capability[CPUID_1_EDX])
 262
 263 extern u32 elf_hwcap2;
 264
 265 /*
 266  * HWCAP2 supplies mask with kernel enabled CPU features, so that
 267  * the application can discover that it can safely use them.
 268  * The bits are defined in uapi/asm/hwcap2.h.
 269  */
 270 #define ELF_HWCAP2              (elf_hwcap2)
 271
 272 /* This yields a string that ld.so will use to load implementation
 273    specific libraries for optimization.  This is more specific in
 274    intent than poking at uname or /proc/cpuinfo.
 275
 276    For the moment, we have only optimizations for the Intel generations,
 277    but that could change... */
 278
 279 #define SET_PERSONALITY(ex) set_personality_64bit()
 280
 281 /*
 282  * An executable for which elf_read_implies_exec() returns TRUE will
 283  * have the READ_IMPLIES_EXEC personality flag set automatically.
 284  */
 285 #define elf_read_implies_exec(ex, executable_stack)     \
 286         (executable_stack != EXSTACK_DISABLE_X)
 287
 288 struct task_struct;
 289
 290 #define ARCH_DLINFO_IA32                                                \
 291 do {                                                                    \
 292         if (VDSO_CURRENT_BASE) {                                        \
 293                 NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY);                    \
 294                 NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE);        \
 295         }                                                               \
 296 } while (0)
 297
 298 /*
 299  * True on X86_32 or when emulating IA32 on X86_64
 300  */
 301 static inline int mmap_is_ia32(void)
 302 {
 303         return IS_ENABLED(CONFIG_X86_32) ||
 304                (IS_ENABLED(CONFIG_COMPAT) &&
 305                 test_thread_flag(TIF_ADDR32));
 306 }
 307
 308 extern unsigned long task_size_32bit(void);
 309 extern unsigned long task_size_64bit(int full_addr_space);
 310 extern unsigned long get_mmap_base(int is_legacy);
 311 extern bool mmap_address_hint_valid(unsigned long addr, unsigned long len);
 312
 313 #ifdef CONFIG_X86_32
 314
 315 #define __STACK_RND_MASK(is32bit) (0x7ff)
 316 #define STACK_RND_MASK (0x7ff)
 317
 318 #define ARCH_DLINFO             ARCH_DLINFO_IA32
 319
 320 /* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
 321
 322 #else /* CONFIG_X86_32 */
 323
 324 /* 1GB for 64bit, 8MB for 32bit */
 325 #define __STACK_RND_MASK(is32bit) ((is32bit) ? 0x7ff : 0x3fffff)
 326 #define STACK_RND_MASK __STACK_RND_MASK(mmap_is_ia32())
 327
 328 #define ARCH_DLINFO                                                     \
 329 do {                                                                    \
 330         if (vdso64_enabled)                                             \
 331                 NEW_AUX_ENT(AT_SYSINFO_EHDR,                            \
 332                             (unsigned long __force)current->mm->context.vdso); \
 333 } while (0)
 334
 335 /* As a historical oddity, the x32 and x86_64 vDSOs are controlled together. */
 336 #define ARCH_DLINFO_X32                                                 \
 337 do {                                                                    \
 338         if (vdso64_enabled)                                             \
 339                 NEW_AUX_ENT(AT_SYSINFO_EHDR,                            \
 340                             (unsigned long __force)current->mm->context.vdso); \
 341 } while (0)
 342
 343 #define AT_SYSINFO              32
 344
 345 #define COMPAT_ARCH_DLINFO                                              \
 346 if (test_thread_flag(TIF_X32))                                          \
 347         ARCH_DLINFO_X32;                                                \
 348 else                                                                    \
 349         ARCH_DLINFO_IA32
 350
 351 #define COMPAT_ELF_ET_DYN_BASE  (TASK_UNMAPPED_BASE + 0x1000000)
 352
 353 #endif /* !CONFIG_X86_32 */
 354
 355 #define VDSO_CURRENT_BASE       ((unsigned long)current->mm->context.vdso)
 356
 357 #define VDSO_ENTRY                                                      \
 358         ((unsigned long)current->mm->context.vdso +                     \
 359          vdso_image_32.sym___kernel_vsyscall)
 360
 361 struct linux_binprm;
 362
 363 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
 364 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
 365                                        int uses_interp);
 366 extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
 367                                               int uses_interp);
 368 #define compat_arch_setup_additional_pages compat_arch_setup_additional_pages
 369
 370 /* Do not change the values. See get_align_mask() */
 371 enum align_flags {
 372         ALIGN_VA_32     = BIT(0),
 373         ALIGN_VA_64     = BIT(1),
 374 };
 375
 376 struct va_alignment {
 377         int flags;
 378         unsigned long mask;
 379         unsigned long bits;
 380 } ____cacheline_aligned;
 381
 382 extern struct va_alignment va_align;
 383 extern unsigned long align_vdso_addr(unsigned long);
 384 #endif /* _ASM_X86_ELF_H */