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 58 offset to GOT */ 59 #define R_X86_64_32 10 /* Direct 32 bit zero extended */ 60 #define R_X86_64_32S 11 /* Direct 32 bit sign extended */ 61 #define R_X86_64_16 12 /* Direct 16 bit zero extended */ 62 #define R_X86_64_PC16 13 /* 16 bit sign extended pc relative */ 63 #define R_X86_64_8 14 /* Direct 8 bit sign extended */ 64 #define R_X86_64_PC8 15 /* 8 bit sign extended pc relative */ 65 #define R_X86_64_PC64 24 /* Place relative 64-bit signed */ 66 67 /* 68 * These are used to set parameters in the core dumps. 69 */ 70 #define ELF_CLASS ELFCLASS64 71 #define ELF_DATA ELFDATA2LSB 72 #define ELF_ARCH EM_X86_64 73 74 #endif 75 76 #include <asm/vdso.h> 77 78 extern unsigned int vdso64_enabled; 79 extern unsigned int vdso32_enabled; 80 81 /* 82 * This is used to ensure we don't load something for the wrong architecture. 83 */ 84 #define elf_check_arch_ia32(x) \ 85 (((x)->e_machine == EM_386) || ((x)->e_machine == EM_486)) 86 87 #include <asm/processor.h> 88 89 #ifdef CONFIG_X86_32 90 #include <asm/desc.h> 91 92 #define elf_check_arch(x) elf_check_arch_ia32(x) 93 94 /* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program starts %edx 95 contains a pointer to a function which might be registered using `atexit'. 96 This provides a mean for the dynamic linker to call DT_FINI functions for 97 shared libraries that have been loaded before the code runs. 98 99 A value of 0 tells we have no such handler. 100 101 We might as well make sure everything else is cleared too (except for %esp), 102 just to make things more deterministic. 103 */ 104 #define ELF_PLAT_INIT(_r, load_addr) \ 105 do { \ 106 _r->bx = 0; _r->cx = 0; _r->dx = 0; \ 107 _r->si = 0; _r->di = 0; _r->bp = 0; \ 108 _r->ax = 0; \ 109 } while (0) 110 111 /* 112 * regs is struct pt_regs, pr_reg is elf_gregset_t (which is 113 * now struct_user_regs, they are different) 114 */ 115 116 #define ELF_CORE_COPY_REGS(pr_reg, regs) \ 117 do { \ 118 pr_reg[0] = regs->bx; \ 119 pr_reg[1] = regs->cx; \ 120 pr_reg[2] = regs->dx; \ 121 pr_reg[3] = regs->si; \ 122 pr_reg[4] = regs->di; \ 123 pr_reg[5] = regs->bp; \ 124 pr_reg[6] = regs->ax; \ 125 pr_reg[7] = regs->ds; \ 126 pr_reg[8] = regs->es; \ 127 pr_reg[9] = regs->fs; \ 128 savesegment(gs, pr_reg[10]); \ 129 pr_reg[11] = regs->orig_ax; \ 130 pr_reg[12] = regs->ip; \ 131 pr_reg[13] = regs->cs; \ 132 pr_reg[14] = regs->flags; \ 133 pr_reg[15] = regs->sp; \ 134 pr_reg[16] = regs->ss; \ 135 } while (0); 136 137 #define ELF_PLATFORM (utsname()->machine) 138 #define set_personality_64bit() do { } while (0) 139 140 #else /* CONFIG_X86_32 */ 141 142 /* 143 * This is used to ensure we don't load something for the wrong architecture. 144 */ 145 #define elf_check_arch(x) \ 146 ((x)->e_machine == EM_X86_64) 147 148 #define compat_elf_check_arch(x) \ 149 ((elf_check_arch_ia32(x) && ia32_enabled_verbose()) || \ 150 (IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64)) 151 152 static inline void elf_common_init(struct thread_struct *t, 153 struct pt_regs *regs, const u16 ds) 154 { 155 /* ax gets execve's return value. */ 156 /*regs->ax = */ regs->bx = regs->cx = regs->dx = 0; 157 regs->si = regs->di = regs->bp = 0; 158 regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0; 159 regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0; 160 t->fsbase = t->gsbase = 0; 161 t->fsindex = t->gsindex = 0; 162 t->ds = t->es = ds; 163 } 164 165 #define ELF_PLAT_INIT(_r, load_addr) \ 166 elf_common_init(¤t->thread, _r, 0) 167 168 #define COMPAT_ELF_PLAT_INIT(regs, load_addr) \ 169 elf_common_init(¤t->thread, regs, __USER_DS) 170 171 void compat_start_thread(struct pt_regs *regs, u32 new_ip, u32 new_sp, bool x32); 172 #define COMPAT_START_THREAD(ex, regs, new_ip, new_sp) \ 173 compat_start_thread(regs, new_ip, new_sp, ex->e_machine == EM_X86_64) 174 175 void set_personality_ia32(bool); 176 #define COMPAT_SET_PERSONALITY(ex) \ 177 set_personality_ia32((ex).e_machine == EM_X86_64) 178 179 #define COMPAT_ELF_PLATFORM ("i686") 180 181 /* 182 * regs is struct pt_regs, pr_reg is elf_gregset_t (which is 183 * now struct_user_regs, they are different). Assumes current is the process 184 * getting dumped. 185 */ 186 187 #define ELF_CORE_COPY_REGS(pr_reg, regs) \ 188 do { \ 189 (pr_reg)[0] = (regs)->r15; \ 190 (pr_reg)[1] = (regs)->r14; \ 191 (pr_reg)[2] = (regs)->r13; \ 192 (pr_reg)[3] = (regs)->r12; \ 193 (pr_reg)[4] = (regs)->bp; \ 194 (pr_reg)[5] = (regs)->bx; \ 195 (pr_reg)[6] = (regs)->r11; \ 196 (pr_reg)[7] = (regs)->r10; \ 197 (pr_reg)[8] = (regs)->r9; \ 198 (pr_reg)[9] = (regs)->r8; \ 199 (pr_reg)[10] = (regs)->ax; \ 200 (pr_reg)[11] = (regs)->cx; \ 201 (pr_reg)[12] = (regs)->dx; \ 202 (pr_reg)[13] = (regs)->si; \ 203 (pr_reg)[14] = (regs)->di; \ 204 (pr_reg)[15] = (regs)->orig_ax; \ 205 (pr_reg)[16] = (regs)->ip; \ 206 (pr_reg)[17] = (regs)->cs; \ 207 (pr_reg)[18] = (regs)->flags; \ 208 (pr_reg)[19] = (regs)->sp; \ 209 (pr_reg)[20] = (regs)->ss; \ 210 (pr_reg)[21] = x86_fsbase_read_cpu(); \ 211 (pr_reg)[22] = x86_gsbase_read_cpu_inactive(); \ 212 savesegment(ds, (pr_reg)[23]); \ 213 savesegment(es, (pr_reg)[24]); \ 214 savesegment(fs, (pr_reg)[25]); \ 215 savesegment(gs, (pr_reg)[26]); \ 216 } while (0); 217 218 /* I'm not sure if we can use '-' here */ 219 #define ELF_PLATFORM ("x86_64") 220 extern void set_personality_64bit(void); 221 extern int force_personality32; 222 223 #endif /* !CONFIG_X86_32 */ 224 225 #define CORE_DUMP_USE_REGSET 226 #define ELF_EXEC_PAGESIZE 4096 227 228 /* 229 * This is the base location for PIE (ET_DYN with INTERP) loads. On 230 * 64-bit, this is above 4GB to leave the entire 32-bit address 231 * space open for things that want to use the area for 32-bit pointers. 232 */ 233 #define ELF_ET_DYN_BASE (mmap_is_ia32() ? 0x000400000UL : \ 234 (DEFAULT_MAP_WINDOW / 3 * 2)) 235 236 /* This yields a mask that user programs can use to figure out what 237 instruction set this CPU supports. This could be done in user space, 238 but it's not easy, and we've already done it here. */ 239 240 #define ELF_HWCAP (boot_cpu_data.x86_capability[CPUID_1_EDX]) 241 242 extern u32 elf_hwcap2; 243 244 /* 245 * HWCAP2 supplies mask with kernel enabled CPU features, so that 246 * the application can discover that it can safely use them. 247 * The bits are defined in uapi/asm/hwcap2.h. 248 */ 249 #define ELF_HWCAP2 (elf_hwcap2) 250 251 /* This yields a string that ld.so will use to load implementation 252 specific libraries for optimization. This is more specific in 253 intent than poking at uname or /proc/cpuinfo. 254 255 For the moment, we have only optimizations for the Intel generations, 256 but that could change... */ 257 258 #define SET_PERSONALITY(ex) set_personality_64bit() 259 260 /* 261 * An executable for which elf_read_implies_exec() returns TRUE will 262 * have the READ_IMPLIES_EXEC personality flag set automatically. 263 * 264 * The decision process for determining the results are: 265 * 266 * CPU: | lacks NX* | has NX, ia32 | has NX, x86_64 | 267 * ELF: | | | | 268 * ---------------------|------------|------------------|----------------| 269 * missing PT_GNU_STACK | exec-all | exec-all | exec-none | 270 * PT_GNU_STACK == RWX | exec-stack | exec-stack | exec-stack | 271 * PT_GNU_STACK == RW | exec-none | exec-none | exec-none | 272 * 273 * exec-all : all PROT_READ user mappings are executable, except when 274 * backed by files on a noexec-filesystem. 275 * exec-none : only PROT_EXEC user mappings are executable. 276 * exec-stack: only the stack and PROT_EXEC user mappings are executable. 277 * 278 * *this column has no architectural effect: NX markings are ignored by 279 * hardware, but may have behavioral effects when "wants X" collides with 280 * "cannot be X" constraints in memory permission flags, as in 281 * https://lkml.kernel.org/r/20190418055759.GA3155@mellanox.com 282 * 283 */ 284 #define elf_read_implies_exec(ex, executable_stack) \ 285 (mmap_is_ia32() && executable_stack == EXSTACK_DEFAULT) 286 287 struct task_struct; 288 289 #define ARCH_DLINFO_IA32 \ 290 do { \ 291 if (VDSO_CURRENT_BASE) { \ 292 NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY); \ 293 NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE); \ 294 } \ 295 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \ 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 extern unsigned long get_sigframe_size(void); 313 314 #ifdef CONFIG_X86_32 315 316 #define __STACK_RND_MASK(is32bit) (0x7ff) 317 #define STACK_RND_MASK (0x7ff) 318 319 #define ARCH_DLINFO ARCH_DLINFO_IA32 320 321 /* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */ 322 323 #else /* CONFIG_X86_32 */ 324 325 /* 1GB for 64bit, 8MB for 32bit */ 326 #define __STACK_RND_MASK(is32bit) ((is32bit) ? 0x7ff : 0x3fffff) 327 #define STACK_RND_MASK __STACK_RND_MASK(mmap_is_ia32()) 328 329 #define ARCH_DLINFO \ 330 do { \ 331 if (vdso64_enabled) \ 332 NEW_AUX_ENT(AT_SYSINFO_EHDR, \ 333 (unsigned long __force)current->mm->context.vdso); \ 334 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \ 335 } while (0) 336 337 /* As a historical oddity, the x32 and x86_64 vDSOs are controlled together. */ 338 #define ARCH_DLINFO_X32 \ 339 do { \ 340 if (vdso64_enabled) \ 341 NEW_AUX_ENT(AT_SYSINFO_EHDR, \ 342 (unsigned long __force)current->mm->context.vdso); \ 343 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \ 344 } while (0) 345 346 #define AT_SYSINFO 32 347 348 #define COMPAT_ARCH_DLINFO \ 349 if (exec->e_machine == EM_X86_64) \ 350 ARCH_DLINFO_X32; \ 351 else if (IS_ENABLED(CONFIG_IA32_EMULATION)) \ 352 ARCH_DLINFO_IA32 353 354 #define COMPAT_ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000) 355 356 #endif /* !CONFIG_X86_32 */ 357 358 #define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso) 359 360 #define VDSO_ENTRY \ 361 ((unsigned long)current->mm->context.vdso + \ 362 vdso32_image.sym___kernel_vsyscall) 363 364 struct linux_binprm; 365 366 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 367 extern int arch_setup_additional_pages(struct linux_binprm *bprm, 368 int uses_interp); 369 extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm, 370 int uses_interp, bool x32); 371 #define COMPAT_ARCH_SETUP_ADDITIONAL_PAGES(bprm, ex, interpreter) \ 372 compat_arch_setup_additional_pages(bprm, interpreter, \ 373 (ex->e_machine == EM_X86_64)) 374 375 extern bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs); 376 377 /* Do not change the values. See get_align_mask() */ 378 enum align_flags { 379 ALIGN_VA_32 = BIT(0), 380 ALIGN_VA_64 = BIT(1), 381 }; 382 383 struct va_alignment { 384 int flags; 385 unsigned long mask; 386 unsigned long bits; 387 } ____cacheline_aligned; 388 389 extern struct va_alignment va_align; 390 #endif /* _ASM_X86_ELF_H */ 391