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Diffstat (limited to 'arch/arm64/include/asm/elf.h')
-rw-r--r--arch/arm64/include/asm/elf.h153
1 files changed, 120 insertions, 33 deletions
diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
index acae781f7359..d2779d604c7b 100644
--- a/arch/arm64/include/asm/elf.h
+++ b/arch/arm64/include/asm/elf.h
@@ -1,17 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_ELF_H
#define __ASM_ELF_H
@@ -107,19 +96,51 @@
*/
#define elf_check_arch(x) ((x)->e_machine == EM_AARCH64)
-#define elf_read_implies_exec(ex,stk) (stk != EXSTACK_DISABLE_X)
+/*
+ * An executable for which elf_read_implies_exec() returns TRUE will
+ * have the READ_IMPLIES_EXEC personality flag set automatically.
+ *
+ * The decision process for determining the results are:
+ *
+ *              CPU*: | arm32    | arm64 |
+ * ELF:              |            |            |
+ * ---------------------|------------|------------|
+ * missing PT_GNU_STACK | exec-all   | exec-none  |
+ * PT_GNU_STACK == RWX  | exec-stack | exec-stack |
+ * PT_GNU_STACK == RW   | exec-none | exec-none |
+ *
+ * exec-all : all PROT_READ user mappings are executable, except when
+ * backed by files on a noexec-filesystem.
+ * exec-none : only PROT_EXEC user mappings are executable.
+ * exec-stack: only the stack and PROT_EXEC user mappings are executable.
+ *
+ * *all arm64 CPUs support NX, so there is no "lacks NX" column.
+ *
+ */
+#define compat_elf_read_implies_exec(ex, stk) (stk == EXSTACK_DEFAULT)
#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 raised to 4GB to leave the entire 32-bit address
+ * 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.
*/
-#define ELF_ET_DYN_BASE 0x100000000UL
+#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__
+#ifndef __ASSEMBLER__
+
+#include <uapi/linux/elf.h>
+#include <linux/bug.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <asm/processor.h> /* for signal_minsigstksz, used by ARCH_DLINFO */
typedef unsigned long elf_greg_t;
@@ -139,7 +160,6 @@ typedef struct user_fpsimd_state elf_fpregset_t;
#define SET_PERSONALITY(ex) \
({ \
- clear_bit(TIF_32BIT, &current->mm->context.flags); \
clear_thread_flag(TIF_32BIT); \
current->personality &= ~READ_IMPLIES_EXEC; \
})
@@ -149,6 +169,16 @@ typedef struct user_fpsimd_state elf_fpregset_t;
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
@@ -171,41 +201,98 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,
#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];
+#ifdef CONFIG_COMPAT
+
+/* PIE load location for compat arm. Must match ARM ELF_ET_DYN_BASE. */
+#define COMPAT_ELF_ET_DYN_BASE 0x000400000UL
+
/* 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))
-
+int compat_elf_check_arch(const struct elf32_hdr *);
+#define compat_elf_check_arch compat_elf_check_arch
#define compat_start_thread compat_start_thread
/*
- * Unlike the native SET_PERSONALITY macro, the compat version inherits
- * READ_IMPLIES_EXEC across a fork() since this is the behaviour on
+ * 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_bit(TIF_32BIT, &current->mm->context.flags); \
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
-extern int aarch32_setup_vectors_page(struct linux_binprm *bprm,
- int uses_interp);
+#endif
+extern int aarch32_setup_additional_pages(struct linux_binprm *bprm,
+ int uses_interp);
#define compat_arch_setup_additional_pages \
- aarch32_setup_vectors_page
+ aarch32_setup_additional_pages
#endif /* CONFIG_COMPAT */
-#endif /* !__ASSEMBLY__ */
+struct arch_elf_state {
+ int flags;
+};
+
+#define ARM64_ELF_BTI (1 << 0)
+
+#define INIT_ARCH_ELF_STATE { \
+ .flags = 0, \
+}
+
+static inline int arch_parse_elf_property(u32 type, const void *data,
+ size_t datasz, bool compat,
+ struct arch_elf_state *arch)
+{
+ /* No known properties for AArch32 yet */
+ if (IS_ENABLED(CONFIG_COMPAT) && compat)
+ return 0;
+
+ if (type == GNU_PROPERTY_AARCH64_FEATURE_1_AND) {
+ const u32 *p = data;
+
+ if (datasz != sizeof(*p))
+ return -ENOEXEC;
+
+ if (system_supports_bti() &&
+ (*p & GNU_PROPERTY_AARCH64_FEATURE_1_BTI))
+ arch->flags |= ARM64_ELF_BTI;
+ }
+
+ return 0;
+}
+
+static inline int arch_elf_pt_proc(void *ehdr, void *phdr,
+ struct file *f, bool is_interp,
+ struct arch_elf_state *state)
+{
+ return 0;
+}
+
+static inline int arch_check_elf(void *ehdr, bool has_interp,
+ void *interp_ehdr,
+ struct arch_elf_state *state)
+{
+ return 0;
+}
+
+#endif /* !__ASSEMBLER__ */
#endif