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 16 typedef unsigned long elf_greg_t; 17 18 #define ELF_NGREG (sizeof(struct user_regs_struct) / sizeof(elf_greg_t)) 19 typedef elf_greg_t elf_gregset_t[ELF_NGREG]; 20 21 typedef 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 offset to GOT */ 58 #define R_X86_64_GOTPCRELX 41 59 #define R_X86_64_REX_GOTPCRELX 42 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 extern unsigned int vdso64_enabled; 80 extern unsigned int vdso32_enabled; 81 82 /* 83 * This is used to ensure we don't load something for the wrong architecture. 84 */ 85 #define elf_check_arch_ia32(x) \ 86 (((x)->e_machine == EM_386) || ((x)->e_machine == EM_486)) 87 88 #include <asm/processor.h> 89 90 #ifdef CONFIG_X86_32 91 #include <asm/desc.h> 92 93 #define elf_check_arch(x) elf_check_arch_ia32(x) 94 95 /* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program starts %edx 96 contains a pointer to a function which might be registered using `atexit'. 97 This provides a mean for the dynamic linker to call DT_FINI functions for 98 shared libraries that have been loaded before the code runs. 99 100 A value of 0 tells we have no such handler. 101 102 We might as well make sure everything else is cleared too (except for %esp), 103 just to make things more deterministic. 104 */ 105 #define ELF_PLAT_INIT(_r, load_addr) \ 106 do { \ 107 _r->bx = 0; _r->cx = 0; _r->dx = 0; \ 108 _r->si = 0; _r->di = 0; _r->bp = 0; \ 109 _r->ax = 0; \ 110 } while (0) 111 112 /* 113 * regs is struct pt_regs, pr_reg is elf_gregset_t (which is 114 * now struct_user_regs, they are different) 115 */ 116 117 #define ELF_CORE_COPY_REGS(pr_reg, regs) \ 118 do { \ 119 pr_reg[0] = regs->bx; \ 120 pr_reg[1] = regs->cx; \ 121 pr_reg[2] = regs->dx; \ 122 pr_reg[3] = regs->si; \ 123 pr_reg[4] = regs->di; \ 124 pr_reg[5] = regs->bp; \ 125 pr_reg[6] = regs->ax; \ 126 pr_reg[7] = regs->ds; \ 127 pr_reg[8] = regs->es; \ 128 pr_reg[9] = regs->fs; \ 129 savesegment(gs, pr_reg[10]); \ 130 pr_reg[11] = regs->orig_ax; \ 131 pr_reg[12] = regs->ip; \ 132 pr_reg[13] = regs->cs; \ 133 pr_reg[14] = regs->flags; \ 134 pr_reg[15] = regs->sp; \ 135 pr_reg[16] = regs->ss; \ 136 } while (0); 137 138 #define ELF_PLATFORM (utsname()->machine) 139 #define set_personality_64bit() do { } while (0) 140 141 #else /* CONFIG_X86_32 */ 142 143 /* 144 * This is used to ensure we don't load something for the wrong architecture. 145 */ 146 #define elf_check_arch(x) \ 147 ((x)->e_machine == EM_X86_64) 148 149 #define compat_elf_check_arch(x) \ 150 ((elf_check_arch_ia32(x) && ia32_enabled_verbose()) || \ 151 (IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64)) 152 153 static inline void elf_common_init(struct thread_struct *t, 154 struct pt_regs *regs, const u16 ds) 155 { 156 /* ax gets execve's return value. */ 157 /*regs->ax = */ regs->bx = regs->cx = regs->dx = 0; 158 regs->si = regs->di = regs->bp = 0; 159 regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0; 160 regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0; 161 t->fsbase = t->gsbase = 0; 162 t->fsindex = t->gsindex = 0; 163 t->ds = t->es = ds; 164 } 165 166 #define ELF_PLAT_INIT(_r, load_addr) \ 167 elf_common_init(¤t->thread, _r, 0) 168 169 #define COMPAT_ELF_PLAT_INIT(regs, load_addr) \ 170 elf_common_init(¤t->thread, regs, __USER_DS) 171 172 void compat_start_thread(struct pt_regs *regs, u32 new_ip, u32 new_sp, bool x32); 173 #define COMPAT_START_THREAD(ex, regs, new_ip, new_sp) \ 174 compat_start_thread(regs, new_ip, new_sp, ex->e_machine == EM_X86_64) 175 176 void set_personality_ia32(bool); 177 #define COMPAT_SET_PERSONALITY(ex) \ 178 set_personality_ia32((ex).e_machine == EM_X86_64) 179 180 #define COMPAT_ELF_PLATFORM ("i686") 181 182 /* 183 * regs is struct pt_regs, pr_reg is elf_gregset_t (which is 184 * now struct_user_regs, they are different). Assumes current is the process 185 * getting dumped. 186 */ 187 188 #define ELF_CORE_COPY_REGS(pr_reg, regs) \ 189 do { \ 190 unsigned v; \ 191 (pr_reg)[0] = (regs)->r15; \ 192 (pr_reg)[1] = (regs)->r14; \ 193 (pr_reg)[2] = (regs)->r13; \ 194 (pr_reg)[3] = (regs)->r12; \ 195 (pr_reg)[4] = (regs)->bp; \ 196 (pr_reg)[5] = (regs)->bx; \ 197 (pr_reg)[6] = (regs)->r11; \ 198 (pr_reg)[7] = (regs)->r10; \ 199 (pr_reg)[8] = (regs)->r9; \ 200 (pr_reg)[9] = (regs)->r8; \ 201 (pr_reg)[10] = (regs)->ax; \ 202 (pr_reg)[11] = (regs)->cx; \ 203 (pr_reg)[12] = (regs)->dx; \ 204 (pr_reg)[13] = (regs)->si; \ 205 (pr_reg)[14] = (regs)->di; \ 206 (pr_reg)[15] = (regs)->orig_ax; \ 207 (pr_reg)[16] = (regs)->ip; \ 208 (pr_reg)[17] = (regs)->cs; \ 209 (pr_reg)[18] = (regs)->flags; \ 210 (pr_reg)[19] = (regs)->sp; \ 211 (pr_reg)[20] = (regs)->ss; \ 212 (pr_reg)[21] = x86_fsbase_read_cpu(); \ 213 (pr_reg)[22] = x86_gsbase_read_cpu_inactive(); \ 214 asm("movl %%ds,%0" : "=r" (v)); (pr_reg)[23] = v; \ 215 asm("movl %%es,%0" : "=r" (v)); (pr_reg)[24] = v; \ 216 asm("movl %%fs,%0" : "=r" (v)); (pr_reg)[25] = v; \ 217 asm("movl %%gs,%0" : "=r" (v)); (pr_reg)[26] = v; \ 218 } while (0); 219 220 /* I'm not sure if we can use '-' here */ 221 #define ELF_PLATFORM ("x86_64") 222 extern void set_personality_64bit(void); 223 extern int force_personality32; 224 225 #endif /* !CONFIG_X86_32 */ 226 227 #define CORE_DUMP_USE_REGSET 228 #define ELF_EXEC_PAGESIZE 4096 229 230 /* 231 * This is the base location for PIE (ET_DYN with INTERP) loads. On 232 * 64-bit, this is above 4GB to leave the entire 32-bit address 233 * space open for things that want to use the area for 32-bit pointers. 234 */ 235 #define ELF_ET_DYN_BASE (mmap_is_ia32() ? 0x000400000UL : \ 236 (DEFAULT_MAP_WINDOW / 3 * 2)) 237 238 /* This yields a mask that user programs can use to figure out what 239 instruction set this CPU supports. This could be done in user space, 240 but it's not easy, and we've already done it here. */ 241 242 #define ELF_HWCAP (boot_cpu_data.x86_capability[CPUID_1_EDX]) 243 244 extern u32 elf_hwcap2; 245 246 /* 247 * HWCAP2 supplies mask with kernel enabled CPU features, so that 248 * the application can discover that it can safely use them. 249 * The bits are defined in uapi/asm/hwcap2.h. 250 */ 251 #define ELF_HWCAP2 (elf_hwcap2) 252 253 /* This yields a string that ld.so will use to load implementation 254 specific libraries for optimization. This is more specific in 255 intent than poking at uname or /proc/cpuinfo. 256 257 For the moment, we have only optimizations for the Intel generations, 258 but that could change... */ 259 260 #define SET_PERSONALITY(ex) set_personality_64bit() 261 262 /* 263 * An executable for which elf_read_implies_exec() returns TRUE will 264 * have the READ_IMPLIES_EXEC personality flag set automatically. 265 * 266 * The decision process for determining the results are: 267 * 268 * CPU: | lacks NX* | has NX, ia32 | has NX, x86_64 | 269 * ELF: | | | | 270 * ---------------------|------------|------------------|----------------| 271 * missing PT_GNU_STACK | exec-all | exec-all | exec-none | 272 * PT_GNU_STACK == RWX | exec-stack | exec-stack | exec-stack | 273 * PT_GNU_STACK == RW | exec-none | exec-none | exec-none | 274 * 275 * exec-all : all PROT_READ user mappings are executable, except when 276 * backed by files on a noexec-filesystem. 277 * exec-none : only PROT_EXEC user mappings are executable. 278 * exec-stack: only the stack and PROT_EXEC user mappings are executable. 279 * 280 * *this column has no architectural effect: NX markings are ignored by 281 * hardware, but may have behavioral effects when "wants X" collides with 282 * "cannot be X" constraints in memory permission flags, as in 283 * https://lkml.kernel.org/r/20190418055759.GA3155@mellanox.com 284 * 285 */ 286 #define elf_read_implies_exec(ex, executable_stack) \ 287 (mmap_is_ia32() && executable_stack == EXSTACK_DEFAULT) 288 289 struct task_struct; 290 291 #define ARCH_DLINFO_IA32 \ 292 do { \ 293 if (VDSO_CURRENT_BASE) { \ 294 NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY); \ 295 NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE); \ 296 } \ 297 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \ 298 } while (0) 299 300 /* 301 * True on X86_32 or when emulating IA32 on X86_64 302 */ 303 static inline int mmap_is_ia32(void) 304 { 305 return IS_ENABLED(CONFIG_X86_32) || 306 (IS_ENABLED(CONFIG_COMPAT) && 307 test_thread_flag(TIF_ADDR32)); 308 } 309 310 extern unsigned long task_size_32bit(void); 311 extern unsigned long task_size_64bit(int full_addr_space); 312 extern unsigned long get_mmap_base(int is_legacy); 313 extern bool mmap_address_hint_valid(unsigned long addr, unsigned long len); 314 extern unsigned long get_sigframe_size(void); 315 316 #ifdef CONFIG_X86_32 317 318 #define __STACK_RND_MASK(is32bit) (0x7ff) 319 #define STACK_RND_MASK (0x7ff) 320 321 #define ARCH_DLINFO ARCH_DLINFO_IA32 322 323 /* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */ 324 325 #else /* CONFIG_X86_32 */ 326 327 /* 1GB for 64bit, 8MB for 32bit */ 328 #define __STACK_RND_MASK(is32bit) ((is32bit) ? 0x7ff : 0x3fffff) 329 #define STACK_RND_MASK __STACK_RND_MASK(mmap_is_ia32()) 330 331 #define ARCH_DLINFO \ 332 do { \ 333 if (vdso64_enabled) \ 334 NEW_AUX_ENT(AT_SYSINFO_EHDR, \ 335 (unsigned long __force)current->mm->context.vdso); \ 336 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \ 337 } while (0) 338 339 /* As a historical oddity, the x32 and x86_64 vDSOs are controlled together. */ 340 #define ARCH_DLINFO_X32 \ 341 do { \ 342 if (vdso64_enabled) \ 343 NEW_AUX_ENT(AT_SYSINFO_EHDR, \ 344 (unsigned long __force)current->mm->context.vdso); \ 345 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \ 346 } while (0) 347 348 #define AT_SYSINFO 32 349 350 #define COMPAT_ARCH_DLINFO \ 351 if (exec->e_machine == EM_X86_64) \ 352 ARCH_DLINFO_X32; \ 353 else if (IS_ENABLED(CONFIG_IA32_EMULATION)) \ 354 ARCH_DLINFO_IA32 355 356 #define COMPAT_ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000) 357 358 #endif /* !CONFIG_X86_32 */ 359 360 #define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso) 361 362 #define VDSO_ENTRY \ 363 ((unsigned long)current->mm->context.vdso + \ 364 vdso_image_32.sym___kernel_vsyscall) 365 366 struct linux_binprm; 367 368 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 369 extern int arch_setup_additional_pages(struct linux_binprm *bprm, 370 int uses_interp); 371 extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm, 372 int uses_interp, bool x32); 373 #define COMPAT_ARCH_SETUP_ADDITIONAL_PAGES(bprm, ex, interpreter) \ 374 compat_arch_setup_additional_pages(bprm, interpreter, \ 375 (ex->e_machine == EM_X86_64)) 376 377 extern bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs); 378 379 /* Do not change the values. See get_align_mask() */ 380 enum align_flags { 381 ALIGN_VA_32 = BIT(0), 382 ALIGN_VA_64 = BIT(1), 383 }; 384 385 struct va_alignment { 386 int flags; 387 unsigned long mask; 388 unsigned long bits; 389 } ____cacheline_aligned; 390 391 extern struct va_alignment va_align; 392 #endif /* _ASM_X86_ELF_H */ 393