1
0
Fork 0
mirror of synced 2025-03-06 20:59:54 +01:00
linux/arch/x86/include/asm/proto.h
Nikolay Borisov 61382281e9 x86/entry: Make IA32 syscalls' availability depend on ia32_enabled()
Another major aspect of supporting running of 32bit processes is the
ability to access 32bit syscalls. Such syscalls can be invoked by
using the legacy int 0x80 handler and  sysenter/syscall instructions.

If IA32 emulation is disabled ensure that each of those 3 distinct
mechanisms are also disabled. For int 0x80 a #GP exception would be
generated since the respective descriptor is not going to be loaded at
all. Invoking sysenter will also result in a #GP since IA32_SYSENTER_CS
contains an invalid segment. Finally, syscall instruction cannot really
be disabled so it's configured to execute a minimal handler.

Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230623111409.3047467-6-nik.borisov@suse.com
2023-09-14 13:19:53 +02:00

50 lines
1.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_PROTO_H
#define _ASM_X86_PROTO_H
#include <asm/ldt.h>
struct task_struct;
/* misc architecture specific prototypes */
void syscall_init(void);
#ifdef CONFIG_X86_64
void entry_SYSCALL_64(void);
void entry_SYSCALL_64_safe_stack(void);
void entry_SYSRETQ_unsafe_stack(void);
void entry_SYSRETQ_end(void);
long do_arch_prctl_64(struct task_struct *task, int option, unsigned long arg2);
#endif
#ifdef CONFIG_X86_32
void entry_INT80_32(void);
void entry_SYSENTER_32(void);
void __begin_SYSENTER_singlestep_region(void);
void __end_SYSENTER_singlestep_region(void);
#endif
#ifdef CONFIG_IA32_EMULATION
void entry_SYSENTER_compat(void);
void __end_entry_SYSENTER_compat(void);
void entry_SYSCALL_compat(void);
void entry_SYSCALL_compat_safe_stack(void);
void entry_SYSRETL_compat_unsafe_stack(void);
void entry_SYSRETL_compat_end(void);
void entry_INT80_compat(void);
#ifdef CONFIG_XEN_PV
void xen_entry_INT80_compat(void);
#endif
#else /* !CONFIG_IA32_EMULATION */
#define entry_SYSCALL_compat NULL
#define entry_SYSENTER_compat NULL
#endif
void x86_configure_nx(void);
extern int reboot_force;
long do_arch_prctl_common(int option, unsigned long arg2);
#endif /* _ASM_X86_PROTO_H */