2019-06-03 05:44:50 +00:00
|
|
|
// SPDX-License-Identifier: GPL-2.0-only
|
2012-03-05 11:49:31 +00:00
|
|
|
/*
|
|
|
|
|
* AArch64-specific system calls implementation
|
|
|
|
|
*
|
|
|
|
|
* Copyright (C) 2012 ARM Ltd.
|
|
|
|
|
* Author: Catalin Marinas <catalin.marinas@arm.com>
|
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
#include <linux/compiler.h>
|
|
|
|
|
#include <linux/errno.h>
|
|
|
|
|
#include <linux/fs.h>
|
|
|
|
|
#include <linux/mm.h>
|
|
|
|
|
#include <linux/export.h>
|
|
|
|
|
#include <linux/sched.h>
|
|
|
|
|
#include <linux/slab.h>
|
|
|
|
|
#include <linux/syscalls.h>
|
2018-07-11 13:56:42 +00:00
|
|
|
|
2016-04-18 09:28:37 +00:00
|
|
|
#include <asm/cpufeature.h>
|
2018-07-11 13:56:42 +00:00
|
|
|
#include <asm/syscall.h>
|
2012-03-05 11:49:31 +00:00
|
|
|
|
2018-07-11 13:56:54 +00:00
|
|
|
SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
|
|
|
|
|
unsigned long, prot, unsigned long, flags,
|
2019-04-29 14:27:19 +00:00
|
|
|
unsigned long, fd, unsigned long, off)
|
2012-03-05 11:49:31 +00:00
|
|
|
{
|
|
|
|
|
if (offset_in_page(off) != 0)
|
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
2018-03-11 10:34:46 +00:00
|
|
|
return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
|
2012-03-05 11:49:31 +00:00
|
|
|
}
|
|
|
|
|
|
2016-04-18 09:28:37 +00:00
|
|
|
SYSCALL_DEFINE1(arm64_personality, unsigned int, personality)
|
|
|
|
|
{
|
|
|
|
|
if (personality(personality) == PER_LINUX32 &&
|
|
|
|
|
!system_supports_32bit_el0())
|
|
|
|
|
return -EINVAL;
|
2018-07-11 13:56:52 +00:00
|
|
|
return ksys_personality(personality);
|
2016-04-18 09:28:37 +00:00
|
|
|
}
|
|
|
|
|
|
2019-05-24 22:11:18 +00:00
|
|
|
asmlinkage long sys_ni_syscall(void);
|
|
|
|
|
|
|
|
|
|
asmlinkage long __arm64_sys_ni_syscall(const struct pt_regs *__unused)
|
|
|
|
|
{
|
|
|
|
|
return sys_ni_syscall();
|
|
|
|
|
}
|
|
|
|
|
|
2012-03-05 11:49:31 +00:00
|
|
|
/*
|
|
|
|
|
* Wrappers to pass the pt_regs argument.
|
|
|
|
|
*/
|
2019-05-28 11:39:34 +00:00
|
|
|
#define __arm64_sys_personality __arm64_sys_arm64_personality
|
2012-03-05 11:49:31 +00:00
|
|
|
|
2024-07-04 12:33:34 +00:00
|
|
|
#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native)
|
|
|
|
|
|
arm64: implement syscall wrappers
To minimize the risk of userspace-controlled values being used under
speculation, this patch adds pt_regs based syscall wrappers for arm64,
which pass the minimum set of required userspace values to syscall
implementations. For each syscall, a wrapper which takes a pt_regs
argument is automatically generated, and this extracts the arguments
before calling the "real" syscall implementation.
Each syscall has three functions generated:
* __do_<compat_>sys_<name> is the "real" syscall implementation, with
the expected prototype.
* __se_<compat_>sys_<name> is the sign-extension/narrowing wrapper,
inherited from common code. This takes a series of long parameters,
casting each to the requisite types required by the "real" syscall
implementation in __do_<compat_>sys_<name>.
This wrapper *may* not be necessary on arm64 given the AAPCS rules on
unused register bits, but it seemed safer to keep the wrapper for now.
* __arm64_<compat_>_sys_<name> takes a struct pt_regs pointer, and
extracts *only* the relevant register values, passing these on to the
__se_<compat_>sys_<name> wrapper.
The syscall invocation code is updated to handle the calling convention
required by __arm64_<compat_>_sys_<name>, and passes a single struct
pt_regs pointer.
The compiler can fold the syscall implementation and its wrappers, such
that the overhead of this approach is minimized.
Note that we play games with sys_ni_syscall(). It can't be defined with
SYSCALL_DEFINE0() because we must avoid the possibility of error
injection. Additionally, there are a couple of locations where we need
to call it from C code, and we don't (currently) have a
ksys_ni_syscall(). While it has no wrapper, passing in a redundant
pt_regs pointer is benign per the AAPCS.
When ARCH_HAS_SYSCALL_WRAPPER is selected, no prototype is defines for
sys_ni_syscall(). Since we need to treat it differently for in-kernel
calls and the syscall tables, the prototype is defined as-required.
The wrappers are largely the same as their x86 counterparts, but
simplified as we don't have a variety of compat calling conventions that
require separate stubs. Unlike x86, we have some zero-argument compat
syscalls, and must define COMPAT_SYSCALL_DEFINE0() to ensure that these
are also given an __arm64_compat_sys_ prefix.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-11 13:56:56 +00:00
|
|
|
#undef __SYSCALL
|
|
|
|
|
#define __SYSCALL(nr, sym) asmlinkage long __arm64_##sym(const struct pt_regs *);
|
2024-07-04 12:33:34 +00:00
|
|
|
#include <asm/syscall_table_64.h>
|
arm64: implement syscall wrappers
To minimize the risk of userspace-controlled values being used under
speculation, this patch adds pt_regs based syscall wrappers for arm64,
which pass the minimum set of required userspace values to syscall
implementations. For each syscall, a wrapper which takes a pt_regs
argument is automatically generated, and this extracts the arguments
before calling the "real" syscall implementation.
Each syscall has three functions generated:
* __do_<compat_>sys_<name> is the "real" syscall implementation, with
the expected prototype.
* __se_<compat_>sys_<name> is the sign-extension/narrowing wrapper,
inherited from common code. This takes a series of long parameters,
casting each to the requisite types required by the "real" syscall
implementation in __do_<compat_>sys_<name>.
This wrapper *may* not be necessary on arm64 given the AAPCS rules on
unused register bits, but it seemed safer to keep the wrapper for now.
* __arm64_<compat_>_sys_<name> takes a struct pt_regs pointer, and
extracts *only* the relevant register values, passing these on to the
__se_<compat_>sys_<name> wrapper.
The syscall invocation code is updated to handle the calling convention
required by __arm64_<compat_>_sys_<name>, and passes a single struct
pt_regs pointer.
The compiler can fold the syscall implementation and its wrappers, such
that the overhead of this approach is minimized.
Note that we play games with sys_ni_syscall(). It can't be defined with
SYSCALL_DEFINE0() because we must avoid the possibility of error
injection. Additionally, there are a couple of locations where we need
to call it from C code, and we don't (currently) have a
ksys_ni_syscall(). While it has no wrapper, passing in a redundant
pt_regs pointer is benign per the AAPCS.
When ARCH_HAS_SYSCALL_WRAPPER is selected, no prototype is defines for
sys_ni_syscall(). Since we need to treat it differently for in-kernel
calls and the syscall tables, the prototype is defined as-required.
The wrappers are largely the same as their x86 counterparts, but
simplified as we don't have a variety of compat calling conventions that
require separate stubs. Unlike x86, we have some zero-argument compat
syscalls, and must define COMPAT_SYSCALL_DEFINE0() to ensure that these
are also given an __arm64_compat_sys_ prefix.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-11 13:56:56 +00:00
|
|
|
|
2012-03-05 11:49:31 +00:00
|
|
|
#undef __SYSCALL
|
2019-05-24 22:11:18 +00:00
|
|
|
#define __SYSCALL(nr, sym) [nr] = __arm64_##sym,
|
2012-03-05 11:49:31 +00:00
|
|
|
|
2018-07-11 13:56:49 +00:00
|
|
|
const syscall_fn_t sys_call_table[__NR_syscalls] = {
|
2019-05-24 22:11:18 +00:00
|
|
|
[0 ... __NR_syscalls - 1] = __arm64_sys_ni_syscall,
|
2024-07-04 12:33:34 +00:00
|
|
|
#include <asm/syscall_table_64.h>
|
2012-03-05 11:49:31 +00:00
|
|
|
};
|