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(¤t->thread, _r, 0) 187 188 #define COMPAT_ELF_PLAT_INIT(regs, load_addr) \ 189 elf_common_init(¤t->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 * The decision process for determining the results are: 286 * 287 * CPU: | lacks NX* | has NX, ia32 | has NX, x86_64 | 288 * ELF: | | | | 289 * ---------------------|------------|------------------|----------------| 290 * missing PT_GNU_STACK | exec-all | exec-all | exec-none | 291 * PT_GNU_STACK == RWX | exec-stack | exec-stack | exec-stack | 292 * PT_GNU_STACK == RW | exec-none | exec-none | exec-none | 293 * 294 * exec-all : all PROT_READ user mappings are executable, except when 295 * backed by files on a noexec-filesystem. 296 * exec-none : only PROT_EXEC user mappings are executable. 297 * exec-stack: only the stack and PROT_EXEC user mappings are executable. 298 * 299 * *this column has no architectural effect: NX markings are ignored by 300 * hardware, but may have behavioral effects when "wants X" collides with 301 * "cannot be X" constraints in memory permission flags, as in 302 * https://lkml.kernel.org/r/20190418055759.GA3155@mellanox.com 303 * 304 */ 305 #define elf_read_implies_exec(ex, executable_stack) \ 306 (mmap_is_ia32() && executable_stack == EXSTACK_DEFAULT) 307 308 struct task_struct; 309 310 #define ARCH_DLINFO_IA32 \ 311 do { \ 312 if (VDSO_CURRENT_BASE) { \ 313 NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY); \ 314 NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE); \ 315 } \ 316 } while (0) 317 318 /* 319 * True on X86_32 or when emulating IA32 on X86_64 320 */ 321 static inline int mmap_is_ia32(void) 322 { 323 return IS_ENABLED(CONFIG_X86_32) || 324 (IS_ENABLED(CONFIG_COMPAT) && 325 test_thread_flag(TIF_ADDR32)); 326 } 327 328 extern unsigned long task_size_32bit(void); 329 extern unsigned long task_size_64bit(int full_addr_space); 330 extern unsigned long get_mmap_base(int is_legacy); 331 extern bool mmap_address_hint_valid(unsigned long addr, unsigned long len); 332 333 #ifdef CONFIG_X86_32 334 335 #define __STACK_RND_MASK(is32bit) (0x7ff) 336 #define STACK_RND_MASK (0x7ff) 337 338 #define ARCH_DLINFO ARCH_DLINFO_IA32 339 340 /* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */ 341 342 #else /* CONFIG_X86_32 */ 343 344 /* 1GB for 64bit, 8MB for 32bit */ 345 #define __STACK_RND_MASK(is32bit) ((is32bit) ? 0x7ff : 0x3fffff) 346 #define STACK_RND_MASK __STACK_RND_MASK(mmap_is_ia32()) 347 348 #define ARCH_DLINFO \ 349 do { \ 350 if (vdso64_enabled) \ 351 NEW_AUX_ENT(AT_SYSINFO_EHDR, \ 352 (unsigned long __force)current->mm->context.vdso); \ 353 } while (0) 354 355 /* As a historical oddity, the x32 and x86_64 vDSOs are controlled together. */ 356 #define ARCH_DLINFO_X32 \ 357 do { \ 358 if (vdso64_enabled) \ 359 NEW_AUX_ENT(AT_SYSINFO_EHDR, \ 360 (unsigned long __force)current->mm->context.vdso); \ 361 } while (0) 362 363 #define AT_SYSINFO 32 364 365 #define COMPAT_ARCH_DLINFO \ 366 if (test_thread_flag(TIF_X32)) \ 367 ARCH_DLINFO_X32; \ 368 else \ 369 ARCH_DLINFO_IA32 370 371 #define COMPAT_ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000) 372 373 #endif /* !CONFIG_X86_32 */ 374 375 #define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso) 376 377 #define VDSO_ENTRY \ 378 ((unsigned long)current->mm->context.vdso + \ 379 vdso_image_32.sym___kernel_vsyscall) 380 381 struct linux_binprm; 382 383 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 384 extern int arch_setup_additional_pages(struct linux_binprm *bprm, 385 int uses_interp); 386 extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm, 387 int uses_interp); 388 #define compat_arch_setup_additional_pages compat_arch_setup_additional_pages 389 390 /* Do not change the values. See get_align_mask() */ 391 enum align_flags { 392 ALIGN_VA_32 = BIT(0), 393 ALIGN_VA_64 = BIT(1), 394 }; 395 396 struct va_alignment { 397 int flags; 398 unsigned long mask; 399 unsigned long bits; 400 } ____cacheline_aligned; 401 402 extern struct va_alignment va_align; 403 extern unsigned long align_vdso_addr(unsigned long); 404 #endif /* _ASM_X86_ELF_H */ 405