mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-04-03 12:05:13 +02:00
93745f5f23
PROT_MTE (memory tagging extensions) is not supported on all user mmap() types for various reasons (memory attributes, backing storage, CoW handling). The arm64 arch_validate_flags() function checks whether the VM_MTE_ALLOWED flag has been set for a vma during mmap(), usually by arch_calc_vm_flag_bits(). Linux prior to 6.13 does not support PROT_MTE hugetlb mappings. This was added by commit25c17c4b55("hugetlb: arm64: add mte support"). However, earlier kernels inadvertently set VM_MTE_ALLOWED on (MAP_ANONYMOUS | MAP_HUGETLB) mappings by only checking for MAP_ANONYMOUS. Explicitly check MAP_HUGETLB in arch_calc_vm_flag_bits() and avoid setting VM_MTE_ALLOWED for such mappings. Fixes:9f3419315f("arm64: mte: Add PROT_MTE support to mmap() and mprotect()") Cc: <stable@vger.kernel.org> # 5.10.x-6.12.x Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
83 lines
2.0 KiB
C
83 lines
2.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef __ASM_MMAN_H__
|
|
#define __ASM_MMAN_H__
|
|
|
|
#include <uapi/asm/mman.h>
|
|
|
|
#ifndef BUILD_VDSO
|
|
#include <linux/compiler.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/shmem_fs.h>
|
|
#include <linux/types.h>
|
|
|
|
static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
|
|
unsigned long pkey)
|
|
{
|
|
unsigned long ret = 0;
|
|
|
|
if (system_supports_bti() && (prot & PROT_BTI))
|
|
ret |= VM_ARM64_BTI;
|
|
|
|
if (system_supports_mte() && (prot & PROT_MTE))
|
|
ret |= VM_MTE;
|
|
|
|
#ifdef CONFIG_ARCH_HAS_PKEYS
|
|
if (system_supports_poe()) {
|
|
ret |= pkey & BIT(0) ? VM_PKEY_BIT0 : 0;
|
|
ret |= pkey & BIT(1) ? VM_PKEY_BIT1 : 0;
|
|
ret |= pkey & BIT(2) ? VM_PKEY_BIT2 : 0;
|
|
}
|
|
#endif
|
|
|
|
return ret;
|
|
}
|
|
#define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)
|
|
|
|
static inline unsigned long arch_calc_vm_flag_bits(struct file *file,
|
|
unsigned long flags)
|
|
{
|
|
/*
|
|
* Only allow MTE on anonymous mappings as these are guaranteed to be
|
|
* backed by tags-capable memory. The vm_flags may be overridden by a
|
|
* filesystem supporting MTE (RAM-based).
|
|
*/
|
|
if (system_supports_mte()) {
|
|
if ((flags & MAP_ANONYMOUS) && !(flags & MAP_HUGETLB))
|
|
return VM_MTE_ALLOWED;
|
|
if (shmem_file(file))
|
|
return VM_MTE_ALLOWED;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#define arch_calc_vm_flag_bits(file, flags) arch_calc_vm_flag_bits(file, flags)
|
|
|
|
static inline bool arch_validate_prot(unsigned long prot,
|
|
unsigned long addr __always_unused)
|
|
{
|
|
unsigned long supported = PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM;
|
|
|
|
if (system_supports_bti())
|
|
supported |= PROT_BTI;
|
|
|
|
if (system_supports_mte())
|
|
supported |= PROT_MTE;
|
|
|
|
return (prot & ~supported) == 0;
|
|
}
|
|
#define arch_validate_prot(prot, addr) arch_validate_prot(prot, addr)
|
|
|
|
static inline bool arch_validate_flags(unsigned long vm_flags)
|
|
{
|
|
if (!system_supports_mte())
|
|
return true;
|
|
|
|
/* only allow VM_MTE if VM_MTE_ALLOWED has been set previously */
|
|
return !(vm_flags & VM_MTE) || (vm_flags & VM_MTE_ALLOWED);
|
|
}
|
|
#define arch_validate_flags(vm_flags) arch_validate_flags(vm_flags)
|
|
|
|
#endif /* !BUILD_VDSO */
|
|
|
|
#endif /* ! __ASM_MMAN_H__ */
|