mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-08-05 16:54:27 +00:00
d1d7f01f7c
Mark read-only data actually read-only (simple mprotect), and to be able to test it also implement _nofault accesses. This works by setting up a new "segv_continue" pointer in current, and then when we hit a segfault we change the signal return context so that we continue at that address. The code using this sets it up so that it jumps to a label and then aborts the access that way, returning -EFAULT. It's possible to optimize the ___backtrack_faulted() thing by using asm goto (compiler version dependent) and/or gcc's (not sure if clang has it) &&label extension, but at least in one attempt I made the && caused the compiler to not load -EFAULT into the register in case of jumping to the &&label from the fault handler. So leave it like this for now. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Co-developed-by: Benjamin Berg <benjamin.berg@intel.com> Signed-off-by: Benjamin Berg <benjamin.berg@intel.com> Link: https://patch.msgid.link/20250210160926.420133-2-benjamin@sipsolutions.net Signed-off-by: Johannes Berg <johannes.berg@intel.com>
74 lines
2.1 KiB
C
74 lines
2.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
|
|
*/
|
|
|
|
#ifndef __KERN_UTIL_H__
|
|
#define __KERN_UTIL_H__
|
|
|
|
#include <sysdep/ptrace.h>
|
|
#include <sysdep/faultinfo.h>
|
|
|
|
struct siginfo;
|
|
|
|
extern int uml_exitcode;
|
|
|
|
extern int kmalloc_ok;
|
|
|
|
#define UML_ROUND_UP(addr) \
|
|
((((unsigned long) addr) + PAGE_SIZE - 1) & PAGE_MASK)
|
|
|
|
extern unsigned long alloc_stack(int order, int atomic);
|
|
extern void free_stack(unsigned long stack, int order);
|
|
|
|
struct pt_regs;
|
|
extern void do_signal(struct pt_regs *regs);
|
|
extern void interrupt_end(void);
|
|
extern void relay_signal(int sig, struct siginfo *si, struct uml_pt_regs *regs,
|
|
void *mc);
|
|
|
|
extern unsigned long segv(struct faultinfo fi, unsigned long ip,
|
|
int is_user, struct uml_pt_regs *regs,
|
|
void *mc);
|
|
extern int handle_page_fault(unsigned long address, unsigned long ip,
|
|
int is_write, int is_user, int *code_out);
|
|
|
|
extern unsigned int do_IRQ(int irq, struct uml_pt_regs *regs);
|
|
extern void initial_thread_cb(void (*proc)(void *), void *arg);
|
|
|
|
extern void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs);
|
|
|
|
extern void uml_pm_wake(void);
|
|
|
|
extern int start_uml(void);
|
|
extern void paging_init(void);
|
|
extern int parse_iomem(char *str, int *add);
|
|
|
|
extern void uml_cleanup(void);
|
|
extern void do_uml_exitcalls(void);
|
|
|
|
/*
|
|
* Are we disallowed to sleep? Used to choose between GFP_KERNEL and
|
|
* GFP_ATOMIC.
|
|
*/
|
|
extern int __uml_cant_sleep(void);
|
|
extern int get_current_pid(void);
|
|
extern int copy_from_user_proc(void *to, void *from, int size);
|
|
extern char *uml_strdup(const char *string);
|
|
|
|
extern unsigned long to_irq_stack(unsigned long *mask_out);
|
|
extern unsigned long from_irq_stack(int nested);
|
|
|
|
extern int singlestepping(void);
|
|
|
|
extern void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs,
|
|
void *mc);
|
|
extern void winch(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs,
|
|
void *mc);
|
|
extern void fatal_sigsegv(void) __attribute__ ((noreturn));
|
|
|
|
void um_idle_sleep(void);
|
|
|
|
void kasan_map_memory(void *start, size_t len);
|
|
|
|
#endif
|