linux/arch/x86/include/asm/vsyscall.h
Andy Lutomirski 918ce32509 x86/vsyscall: Show something useful on a read fault
Just segfaulting the application when it tries to read the vsyscall page in
xonly mode is not helpful for those who need to debug it.

Emit a hint.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Jann Horn <jannh@google.com>
Link: https://lkml.kernel.org/r/8016afffe0eab497be32017ad7f6f7030dc3ba66.1561610354.git.luto@kernel.org
2019-06-28 00:04:39 +02:00

28 lines
703 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_VSYSCALL_H
#define _ASM_X86_VSYSCALL_H
#include <linux/seqlock.h>
#include <uapi/asm/vsyscall.h>
#ifdef CONFIG_X86_VSYSCALL_EMULATION
extern void map_vsyscall(void);
extern void set_vsyscall_pgtable_user_bits(pgd_t *root);
/*
* Called on instruction fetch fault in vsyscall page.
* Returns true if handled.
*/
extern bool emulate_vsyscall(unsigned long error_code,
struct pt_regs *regs, unsigned long address);
#else
static inline void map_vsyscall(void) {}
static inline bool emulate_vsyscall(unsigned long error_code,
struct pt_regs *regs, unsigned long address)
{
return false;
}
#endif
#endif /* _ASM_X86_VSYSCALL_H */