mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-16 07:56:49 +07:00
a1aab6f3d2
Pull x86 asm updates from Ingo Molnar: "Most of the changes relate to Peter Zijlstra's cleanup of ptregs handling, in particular the i386 part is now much simplified and standardized - no more partial ptregs stack frames via the esp/ss oddity. This simplifies ftrace, kprobes, the unwinder, ptrace, kdump and kgdb. There's also a CR4 hardening enhancements by Kees Cook, to make the generic platform functions such as native_write_cr4() less useful as ROP gadgets that disable SMEP/SMAP. Also protect the WP bit of CR0 against similar attacks. The rest is smaller cleanups/fixes" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternatives: Add int3_emulate_call() selftest x86/stackframe/32: Allow int3_emulate_push() x86/stackframe/32: Provide consistent pt_regs x86/stackframe, x86/ftrace: Add pt_regs frame annotations x86/stackframe, x86/kprobes: Fix frame pointer annotations x86/stackframe: Move ENCODE_FRAME_POINTER to asm/frame.h x86/entry/32: Clean up return from interrupt preemption path x86/asm: Pin sensitive CR0 bits x86/asm: Pin sensitive CR4 bits Documentation/x86: Fix path to entry_32.S x86/asm: Remove unused TASK_TI_flags from asm-offsets.c
89 lines
2.8 KiB
C
89 lines
2.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_X86_TEXT_PATCHING_H
|
|
#define _ASM_X86_TEXT_PATCHING_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/stddef.h>
|
|
#include <asm/ptrace.h>
|
|
|
|
struct paravirt_patch_site;
|
|
#ifdef CONFIG_PARAVIRT
|
|
void apply_paravirt(struct paravirt_patch_site *start,
|
|
struct paravirt_patch_site *end);
|
|
#else
|
|
static inline void apply_paravirt(struct paravirt_patch_site *start,
|
|
struct paravirt_patch_site *end)
|
|
{}
|
|
#define __parainstructions NULL
|
|
#define __parainstructions_end NULL
|
|
#endif
|
|
|
|
/*
|
|
* Currently, the max observed size in the kernel code is
|
|
* JUMP_LABEL_NOP_SIZE/RELATIVEJUMP_SIZE, which are 5.
|
|
* Raise it if needed.
|
|
*/
|
|
#define POKE_MAX_OPCODE_SIZE 5
|
|
|
|
struct text_poke_loc {
|
|
void *detour;
|
|
void *addr;
|
|
size_t len;
|
|
const char opcode[POKE_MAX_OPCODE_SIZE];
|
|
};
|
|
|
|
extern void text_poke_early(void *addr, const void *opcode, size_t len);
|
|
|
|
/*
|
|
* Clear and restore the kernel write-protection flag on the local CPU.
|
|
* Allows the kernel to edit read-only pages.
|
|
* Side-effect: any interrupt handler running between save and restore will have
|
|
* the ability to write to read-only pages.
|
|
*
|
|
* Warning:
|
|
* Code patching in the UP case is safe if NMIs and MCE handlers are stopped and
|
|
* no thread can be preempted in the instructions being modified (no iret to an
|
|
* invalid instruction possible) or if the instructions are changed from a
|
|
* consistent state to another consistent state atomically.
|
|
* On the local CPU you need to be protected again NMI or MCE handlers seeing an
|
|
* inconsistent instruction while you patch.
|
|
*/
|
|
extern void *text_poke(void *addr, const void *opcode, size_t len);
|
|
extern void *text_poke_kgdb(void *addr, const void *opcode, size_t len);
|
|
extern int poke_int3_handler(struct pt_regs *regs);
|
|
extern void text_poke_bp(void *addr, const void *opcode, size_t len, void *handler);
|
|
extern void text_poke_bp_batch(struct text_poke_loc *tp, unsigned int nr_entries);
|
|
extern int after_bootmem;
|
|
extern __ro_after_init struct mm_struct *poking_mm;
|
|
extern __ro_after_init unsigned long poking_addr;
|
|
|
|
#ifndef CONFIG_UML_X86
|
|
static inline void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip)
|
|
{
|
|
regs->ip = ip;
|
|
}
|
|
|
|
#define INT3_INSN_SIZE 1
|
|
#define CALL_INSN_SIZE 5
|
|
|
|
static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val)
|
|
{
|
|
/*
|
|
* The int3 handler in entry_64.S adds a gap between the
|
|
* stack where the break point happened, and the saving of
|
|
* pt_regs. We can extend the original stack because of
|
|
* this gap. See the idtentry macro's create_gap option.
|
|
*/
|
|
regs->sp -= sizeof(unsigned long);
|
|
*(unsigned long *)regs->sp = val;
|
|
}
|
|
|
|
static inline void int3_emulate_call(struct pt_regs *regs, unsigned long func)
|
|
{
|
|
int3_emulate_push(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE);
|
|
int3_emulate_jmp(regs, func);
|
|
}
|
|
#endif /* !CONFIG_UML_X86 */
|
|
|
|
#endif /* _ASM_X86_TEXT_PATCHING_H */
|