Commit 2f085169 authored May 08, 2020 by Andy Lutomirski Committed by Greg Kroah-Hartman Jun 03, 2020

x86/syscalls: Revert "x86/syscalls: Make __X32_SYSCALL_BIT be unsigned long"



commit 700d3a5a664df267f01ec8887fd2d8ff98f67e7f upstream.

Revert

  45e29d11 ("x86/syscalls: Make __X32_SYSCALL_BIT be unsigned long")

and add a comment to discourage someone else from making the same
mistake again.

It turns out that some user code fails to compile if __X32_SYSCALL_BIT
is unsigned long. See, for example [1] below.

 [ bp: Massage and do the same thing in the respective tools/ header. ]

Fixes: 45e29d11 ("x86/syscalls: Make __X32_SYSCALL_BIT be unsigned long")
Reported-by: Thorsten Glaser <t.glaser@tarent.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@kernel.org
Link: [1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=954294
Link: https://lkml.kernel.org/r/92e55442b744a5951fdc9cfee10badd0a5f7f828.1588983892.git.luto@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 8c1bfa73

arch/x86/include/uapi/asm/unistd.h

+9 −2

Original line number	Diff line number	Diff line
		@@ -2,8 +2,15 @@
		#ifndef _UAPI_ASM_X86_UNISTD_H
		#define _UAPI_ASM_X86_UNISTD_H

		/* x32 syscall flag bit */
		#define __X32_SYSCALL_BIT 0x40000000UL
		/*
		* x32 syscall flag bit. Some user programs expect syscall NR macros
		* and __X32_SYSCALL_BIT to have type int, even though syscall numbers
		* are, for practical purposes, unsigned long.
		*
		* Fortunately, expressions like (nr & ~__X32_SYSCALL_BIT) do the right
		* thing regardless.
		*/
		#define __X32_SYSCALL_BIT 0x40000000

		#ifndef __KERNEL__
		# ifdef __i386__

tools/arch/x86/include/uapi/asm/unistd.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -3,7 +3,7 @@
		#define _UAPI_ASM_X86_UNISTD_H

		/* x32 syscall flag bit */
		#define __X32_SYSCALL_BIT 0x40000000UL
		#define __X32_SYSCALL_BIT 0x40000000

		#ifndef __KERNEL__
		# ifdef __i386__