linux/arch/arm64/include/asm/elf.h
Vincenzo Frascino 85751e9e5b arm64: vdso: Fix population of AT_SYSINFO_EHDR for compat vdso
Prior to the introduction of Unified vDSO support and compat layer for
vDSO on arm64, AT_SYSINFO_EHDR was not defined for compat tasks.
In the current implementation, AT_SYSINFO_EHDR is defined even if the
compat vdso layer is not built, which has been shown to break Android
applications using bionic:

 | 01-01 01:22:14.097   755   755 F libc    : Fatal signal 11 (SIGSEGV),
 | code 1 (SEGV_MAPERR), fault addr 0x3cf2c96c in tid 755 (cameraserver),
 | pid 755 (cameraserver)
 | 01-01 01:22:14.112   759   759 F libc    : Fatal signal 11 (SIGSEGV),
 | code 1 (SEGV_MAPERR), fault addr 0x3cf2c96c in tid 759
 | (android.hardwar), pid 759 (android.hardwar)
 | 01-01 01:22:14.120   756   756 F libc    : Fatal signal 11 (SIGSEGV)
 | code 1 (SEGV_MAPERR), fault addr 0x3cf2c96c in tid 756 (drmserver),
 | pid 756 (drmserver)

Restore the old behaviour by making sure that AT_SYSINFO_EHDR for compat
tasks is defined only when CONFIG_COMPAT_VDSO is enabled.

Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-07-22 10:33:42 +01:00

230 lines
6.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Ltd.
*/
#ifndef __ASM_ELF_H
#define __ASM_ELF_H
#include <asm/hwcap.h>
/*
* ELF register definitions..
*/
#include <asm/ptrace.h>
#include <asm/user.h>
/*
* AArch64 static relocation types.
*/
/* Miscellaneous. */
#define R_ARM_NONE 0
#define R_AARCH64_NONE 256
/* Data. */
#define R_AARCH64_ABS64 257
#define R_AARCH64_ABS32 258
#define R_AARCH64_ABS16 259
#define R_AARCH64_PREL64 260
#define R_AARCH64_PREL32 261
#define R_AARCH64_PREL16 262
/* Instructions. */
#define R_AARCH64_MOVW_UABS_G0 263
#define R_AARCH64_MOVW_UABS_G0_NC 264
#define R_AARCH64_MOVW_UABS_G1 265
#define R_AARCH64_MOVW_UABS_G1_NC 266
#define R_AARCH64_MOVW_UABS_G2 267
#define R_AARCH64_MOVW_UABS_G2_NC 268
#define R_AARCH64_MOVW_UABS_G3 269
#define R_AARCH64_MOVW_SABS_G0 270
#define R_AARCH64_MOVW_SABS_G1 271
#define R_AARCH64_MOVW_SABS_G2 272
#define R_AARCH64_LD_PREL_LO19 273
#define R_AARCH64_ADR_PREL_LO21 274
#define R_AARCH64_ADR_PREL_PG_HI21 275
#define R_AARCH64_ADR_PREL_PG_HI21_NC 276
#define R_AARCH64_ADD_ABS_LO12_NC 277
#define R_AARCH64_LDST8_ABS_LO12_NC 278
#define R_AARCH64_TSTBR14 279
#define R_AARCH64_CONDBR19 280
#define R_AARCH64_JUMP26 282
#define R_AARCH64_CALL26 283
#define R_AARCH64_LDST16_ABS_LO12_NC 284
#define R_AARCH64_LDST32_ABS_LO12_NC 285
#define R_AARCH64_LDST64_ABS_LO12_NC 286
#define R_AARCH64_LDST128_ABS_LO12_NC 299
#define R_AARCH64_MOVW_PREL_G0 287
#define R_AARCH64_MOVW_PREL_G0_NC 288
#define R_AARCH64_MOVW_PREL_G1 289
#define R_AARCH64_MOVW_PREL_G1_NC 290
#define R_AARCH64_MOVW_PREL_G2 291
#define R_AARCH64_MOVW_PREL_G2_NC 292
#define R_AARCH64_MOVW_PREL_G3 293
#define R_AARCH64_RELATIVE 1027
/*
* These are used to set parameters in the core dumps.
*/
#define ELF_CLASS ELFCLASS64
#ifdef __AARCH64EB__
#define ELF_DATA ELFDATA2MSB
#else
#define ELF_DATA ELFDATA2LSB
#endif
#define ELF_ARCH EM_AARCH64
/*
* This yields a string that ld.so will use to load implementation
* specific libraries for optimization. This is more specific in
* intent than poking at uname or /proc/cpuinfo.
*/
#define ELF_PLATFORM_SIZE 16
#ifdef __AARCH64EB__
#define ELF_PLATFORM ("aarch64_be")
#else
#define ELF_PLATFORM ("aarch64")
#endif
/*
* This is used to ensure we don't load something for the wrong architecture.
*/
#define elf_check_arch(x) ((x)->e_machine == EM_AARCH64)
#define elf_read_implies_exec(ex,stk) (stk != EXSTACK_DISABLE_X)
#define CORE_DUMP_USE_REGSET
#define ELF_EXEC_PAGESIZE PAGE_SIZE
/*
* This is the base location for PIE (ET_DYN with INTERP) loads. On
* 64-bit, this is above 4GB to leave the entire 32-bit address
* space open for things that want to use the area for 32-bit pointers.
*/
#ifdef CONFIG_ARM64_FORCE_52BIT
#define ELF_ET_DYN_BASE (2 * TASK_SIZE_64 / 3)
#else
#define ELF_ET_DYN_BASE (2 * DEFAULT_MAP_WINDOW_64 / 3)
#endif /* CONFIG_ARM64_FORCE_52BIT */
#ifndef __ASSEMBLY__
#include <linux/bug.h>
#include <asm/processor.h> /* for signal_minsigstksz, used by ARCH_DLINFO */
typedef unsigned long elf_greg_t;
#define ELF_NGREG (sizeof(struct user_pt_regs) / sizeof(elf_greg_t))
#define ELF_CORE_COPY_REGS(dest, regs) \
*(struct user_pt_regs *)&(dest) = (regs)->user_regs;
typedef elf_greg_t elf_gregset_t[ELF_NGREG];
typedef struct user_fpsimd_state elf_fpregset_t;
/*
* When the program starts, a1 contains a pointer to a function to be
* registered with atexit, as per the SVR4 ABI. A value of 0 means we have no
* such handler.
*/
#define ELF_PLAT_INIT(_r, load_addr) (_r)->regs[0] = 0
#define SET_PERSONALITY(ex) \
({ \
clear_thread_flag(TIF_32BIT); \
current->personality &= ~READ_IMPLIES_EXEC; \
})
/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
#define ARCH_DLINFO \
do { \
NEW_AUX_ENT(AT_SYSINFO_EHDR, \
(elf_addr_t)current->mm->context.vdso); \
\
/* \
* Should always be nonzero unless there's a kernel bug. \
* If we haven't determined a sensible value to give to \
* userspace, omit the entry: \
*/ \
if (likely(signal_minsigstksz)) \
NEW_AUX_ENT(AT_MINSIGSTKSZ, signal_minsigstksz); \
else \
NEW_AUX_ENT(AT_IGNORE, 0); \
} while (0)
#define ARCH_HAS_SETUP_ADDITIONAL_PAGES
struct linux_binprm;
extern int arch_setup_additional_pages(struct linux_binprm *bprm,
int uses_interp);
/* 1GB of VA */
#ifdef CONFIG_COMPAT
#define STACK_RND_MASK (test_thread_flag(TIF_32BIT) ? \
0x7ff >> (PAGE_SHIFT - 12) : \
0x3ffff >> (PAGE_SHIFT - 12))
#else
#define STACK_RND_MASK (0x3ffff >> (PAGE_SHIFT - 12))
#endif
#ifdef __AARCH64EB__
#define COMPAT_ELF_PLATFORM ("v8b")
#else
#define COMPAT_ELF_PLATFORM ("v8l")
#endif
#ifdef CONFIG_COMPAT
/* PIE load location for compat arm. Must match ARM ELF_ET_DYN_BASE. */
#define COMPAT_ELF_ET_DYN_BASE 0x000400000UL
/* AArch32 registers. */
#define COMPAT_ELF_NGREG 18
typedef unsigned int compat_elf_greg_t;
typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_ELF_NGREG];
/* AArch32 EABI. */
#define EF_ARM_EABI_MASK 0xff000000
#define compat_elf_check_arch(x) (system_supports_32bit_el0() && \
((x)->e_machine == EM_ARM) && \
((x)->e_flags & EF_ARM_EABI_MASK))
#define compat_start_thread compat_start_thread
/*
* Unlike the native SET_PERSONALITY macro, the compat version maintains
* READ_IMPLIES_EXEC across an execve() since this is the behaviour on
* arch/arm/.
*/
#define COMPAT_SET_PERSONALITY(ex) \
({ \
set_thread_flag(TIF_32BIT); \
})
#ifdef CONFIG_COMPAT_VDSO
#define COMPAT_ARCH_DLINFO \
do { \
/* \
* Note that we use Elf64_Off instead of elf_addr_t because \
* elf_addr_t in compat is defined as Elf32_Addr and casting \
* current->mm->context.vdso to it triggers a cast warning of \
* cast from pointer to integer of different size. \
*/ \
NEW_AUX_ENT(AT_SYSINFO_EHDR, \
(Elf64_Off)current->mm->context.vdso); \
} while (0)
#else
#define COMPAT_ARCH_DLINFO
#endif
extern int aarch32_setup_additional_pages(struct linux_binprm *bprm,
int uses_interp);
#define compat_arch_setup_additional_pages \
aarch32_setup_additional_pages
#endif /* CONFIG_COMPAT */
#endif /* !__ASSEMBLY__ */
#endif