Commit 5bb7b210 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'x86-urgent-2021-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for X86:

   - Prevent sending the wrong signal when protection keys are enabled
     and the kernel handles a fault in the vsyscall emulation.

   - Invoke early_reserve_memory() before invoking e820_memory_setup()
     which is required to make the Xen dom0 e820 hooks work correctly.

   - Use the correct data type for the SETZ operand in the EMQCMDS
     instruction wrapper.

   - Prevent undefined behaviour to the potential unaligned accesss in
     the instruction decoder library"

* tag 'x86-urgent-2021-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/insn, tools/x86: Fix undefined behavior due to potential unaligned accesses
  x86/asm: Fix SETZ size enqcmds() build failure
  x86/setup: Call early_reserve_memory() earlier
  x86/fault: Fix wrong signal when vsyscall fails with pkey
parents 3a398acc 5ba1071f

arch/x86/include/asm/pkeys.h

+0 −2
Original line number Diff line number Diff line
@@ -2,8 +2,6 @@ 
#ifndef _ASM_X86_PKEYS_H

#define _ASM_X86_PKEYS_H



#define ARCH_DEFAULT_PKEY	0



/*

 * If more than 16 keys are ever supported, a thorough audit

 * will be necessary to ensure that the types that store key

arch/x86/include/asm/special_insns.h

+1 −1
Original line number Diff line number Diff line
@@ -275,7 +275,7 @@ static inline int enqcmds(void __iomem *dst, const void *src) 
{

	const struct { char _[64]; } *__src = src;

	struct { char _[64]; } __iomem *__dst = dst;

	int zf;

	bool zf;



	/*

	 * ENQCMDS %(rdx), rax

arch/x86/kernel/setup.c

+14 −12
Original line number Diff line number Diff line
@@ -830,6 +830,20 @@ void __init setup_arch(char **cmdline_p) 


	x86_init.oem.arch_setup();



	/*

	 * Do some memory reservations *before* memory is added to memblock, so

	 * memblock allocations won't overwrite it.

	 *

	 * After this point, everything still needed from the boot loader or

	 * firmware or kernel text should be early reserved or marked not RAM in

	 * e820. All other memory is free game.

	 *

	 * This call needs to happen before e820__memory_setup() which calls the

	 * xen_memory_setup() on Xen dom0 which relies on the fact that those

	 * early reservations have happened already.

	 */

	early_reserve_memory();



	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;

	e820__memory_setup();

	parse_setup_data();
@@ -876,18 +890,6 @@ void __init setup_arch(char **cmdline_p) 


	parse_early_param();



	/*

	 * Do some memory reservations *before* memory is added to

	 * memblock, so memblock allocations won't overwrite it.

	 * Do it after early param, so we could get (unlikely) panic from

	 * serial.

	 *

	 * After this point everything still needed from the boot loader or

	 * firmware or kernel text should be early reserved or marked not

	 * RAM in e820. All other memory is free game.

	 */

	early_reserve_memory();



#ifdef CONFIG_MEMORY_HOTPLUG

	/*

	 * Memory used by the kernel cannot be hot-removed because Linux

arch/x86/lib/insn.c

+2 −2
Original line number Diff line number Diff line
@@ -37,10 +37,10 @@ 
	((insn)->next_byte + sizeof(t) + n <= (insn)->end_kaddr)



#define __get_next(t, insn)	\

	({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); leXX_to_cpu(t, r); })

	({ t r; memcpy(&r, insn->next_byte, sizeof(t)); insn->next_byte += sizeof(t); leXX_to_cpu(t, r); })



#define __peek_nbyte_next(t, insn, n)	\

	({ t r = *(t*)((insn)->next_byte + n); leXX_to_cpu(t, r); })

	({ t r; memcpy(&r, (insn)->next_byte + n, sizeof(t)); leXX_to_cpu(t, r); })



#define get_next(t, insn)	\

	({ if (unlikely(!validate_next(t, insn, 0))) goto err_out; __get_next(t, insn); })

arch/x86/mm/fault.c

+18 −8
Original line number Diff line number Diff line
@@ -710,7 +710,8 @@ page_fault_oops(struct pt_regs *regs, unsigned long error_code, 


static noinline void

kernelmode_fixup_or_oops(struct pt_regs *regs, unsigned long error_code,

			 unsigned long address, int signal, int si_code)

			 unsigned long address, int signal, int si_code,

			 u32 pkey)

{

	WARN_ON_ONCE(user_mode(regs));
@@ -735,9 +736,13 @@ kernelmode_fixup_or_oops(struct pt_regs *regs, unsigned long error_code, 


			set_signal_archinfo(address, error_code);



			if (si_code == SEGV_PKUERR) {

				force_sig_pkuerr((void __user *)address, pkey);

			} else {

				/* XXX: hwpoison faults will set the wrong code. */

				force_sig_fault(signal, si_code, (void __user *)address);

			}

		}



		/*

		 * Barring that, we can do the fixup and be happy.
@@ -798,7 +803,8 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code, 
	struct task_struct *tsk = current;



	if (!user_mode(regs)) {

		kernelmode_fixup_or_oops(regs, error_code, address, pkey, si_code);

		kernelmode_fixup_or_oops(regs, error_code, address,

					 SIGSEGV, si_code, pkey);

		return;

	}
@@ -930,7 +936,8 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address, 
{

	/* Kernel mode? Handle exceptions or die: */

	if (!user_mode(regs)) {

		kernelmode_fixup_or_oops(regs, error_code, address, SIGBUS, BUS_ADRERR);

		kernelmode_fixup_or_oops(regs, error_code, address,

					 SIGBUS, BUS_ADRERR, ARCH_DEFAULT_PKEY);

		return;

	}
@@ -1396,7 +1403,8 @@ void do_user_addr_fault(struct pt_regs *regs, 
		 */

		if (!user_mode(regs))

			kernelmode_fixup_or_oops(regs, error_code, address,

						 SIGBUS, BUS_ADRERR);

						 SIGBUS, BUS_ADRERR,

						 ARCH_DEFAULT_PKEY);

		return;

	}
@@ -1416,7 +1424,8 @@ void do_user_addr_fault(struct pt_regs *regs, 
		return;



	if (fatal_signal_pending(current) && !user_mode(regs)) {

		kernelmode_fixup_or_oops(regs, error_code, address, 0, 0);

		kernelmode_fixup_or_oops(regs, error_code, address,

					 0, 0, ARCH_DEFAULT_PKEY);

		return;

	}
@@ -1424,7 +1433,8 @@ void do_user_addr_fault(struct pt_regs *regs, 
		/* Kernel mode? Handle exceptions or die: */

		if (!user_mode(regs)) {

			kernelmode_fixup_or_oops(regs, error_code, address,

						 SIGSEGV, SEGV_MAPERR);

						 SIGSEGV, SEGV_MAPERR,

						 ARCH_DEFAULT_PKEY);

			return;

		}