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arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_MMAN_H__
#define __ASM_MMAN_H__
arm64: vDSO: Wire up getrandom() vDSO implementation Hook up the generic vDSO implementation to the aarch64 vDSO data page. The _vdso_rng_data required data is placed within the _vdso_data vvar page, by using a offset larger than the vdso_data. The vDSO function requires a ChaCha20 implementation that does not write to the stack, and that can do an entire ChaCha20 permutation. The one provided uses NEON on the permute operation, with a fallback to the syscall for chips that do not support AdvSIMD. This also passes the vdso_test_chacha test along with vdso_test_getrandom. The vdso_test_getrandom bench-single result on Neoverse-N1 shows: vdso: 25000000 times in 0.783884250 seconds libc: 25000000 times in 8.780275399 seconds syscall: 25000000 times in 8.786581518 seconds A small fixup to arch/arm64/include/asm/mman.h was required to avoid pulling kernel code into the vDSO, similar to what's already done in arch/arm64/include/asm/rwonce.h. Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2024-09-03 12:09:17 +00:00
#include <uapi/asm/mman.h>
#ifndef BUILD_VDSO
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
#include <linux/compiler.h>
mm: refactor arch_calc_vm_flag_bits() and arm64 MTE handling Currently MTE is permitted in two circumstances (desiring to use MTE having been specified by the VM_MTE flag) - where MAP_ANONYMOUS is specified, as checked by arch_calc_vm_flag_bits() and actualised by setting the VM_MTE_ALLOWED flag, or if the file backing the mapping is shmem, in which case we set VM_MTE_ALLOWED in shmem_mmap() when the mmap hook is activated in mmap_region(). The function that checks that, if VM_MTE is set, VM_MTE_ALLOWED is also set is the arm64 implementation of arch_validate_flags(). Unfortunately, we intend to refactor mmap_region() to perform this check earlier, meaning that in the case of a shmem backing we will not have invoked shmem_mmap() yet, causing the mapping to fail spuriously. It is inappropriate to set this architecture-specific flag in general mm code anyway, so a sensible resolution of this issue is to instead move the check somewhere else. We resolve this by setting VM_MTE_ALLOWED much earlier in do_mmap(), via the arch_calc_vm_flag_bits() call. This is an appropriate place to do this as we already check for the MAP_ANONYMOUS case here, and the shmem file case is simply a variant of the same idea - we permit RAM-backed memory. This requires a modification to the arch_calc_vm_flag_bits() signature to pass in a pointer to the struct file associated with the mapping, however this is not too egregious as this is only used by two architectures anyway - arm64 and parisc. So this patch performs this adjustment and removes the unnecessary assignment of VM_MTE_ALLOWED in shmem_mmap(). [akpm@linux-foundation.org: fix whitespace, per Catalin] Link: https://lkml.kernel.org/r/ec251b20ba1964fb64cf1607d2ad80c47f3873df.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andreas Larsson <andreas@gaisler.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-10-29 18:11:47 +00:00
#include <linux/fs.h>
arm64: mte: set VM_MTE_ALLOWED for hugetlbfs at correct place The commit 5de195060b2e ("mm: resolve faulty mmap_region() error path behaviour") moved vm flags validation before fop->mmap for file mappings. But when commit 25c17c4b55de ("hugetlb: arm64: add mte support") was rebased on top of it, the hugetlbfs part was missed. Mmapping hugetlbfs file may not have MAP_HUGETLB set. Fixes: 25c17c4b55de ("hugetlb: arm64: add mte support") Signed-off-by: Yang Shi <yang@os.amperecomputing.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20241119200914.1145249-1-yang@os.amperecomputing.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-19 12:09:14 -08:00
#include <linux/hugetlb.h>
mm: refactor arch_calc_vm_flag_bits() and arm64 MTE handling Currently MTE is permitted in two circumstances (desiring to use MTE having been specified by the VM_MTE flag) - where MAP_ANONYMOUS is specified, as checked by arch_calc_vm_flag_bits() and actualised by setting the VM_MTE_ALLOWED flag, or if the file backing the mapping is shmem, in which case we set VM_MTE_ALLOWED in shmem_mmap() when the mmap hook is activated in mmap_region(). The function that checks that, if VM_MTE is set, VM_MTE_ALLOWED is also set is the arm64 implementation of arch_validate_flags(). Unfortunately, we intend to refactor mmap_region() to perform this check earlier, meaning that in the case of a shmem backing we will not have invoked shmem_mmap() yet, causing the mapping to fail spuriously. It is inappropriate to set this architecture-specific flag in general mm code anyway, so a sensible resolution of this issue is to instead move the check somewhere else. We resolve this by setting VM_MTE_ALLOWED much earlier in do_mmap(), via the arch_calc_vm_flag_bits() call. This is an appropriate place to do this as we already check for the MAP_ANONYMOUS case here, and the shmem file case is simply a variant of the same idea - we permit RAM-backed memory. This requires a modification to the arch_calc_vm_flag_bits() signature to pass in a pointer to the struct file associated with the mapping, however this is not too egregious as this is only used by two architectures anyway - arm64 and parisc. So this patch performs this adjustment and removes the unnecessary assignment of VM_MTE_ALLOWED in shmem_mmap(). [akpm@linux-foundation.org: fix whitespace, per Catalin] Link: https://lkml.kernel.org/r/ec251b20ba1964fb64cf1607d2ad80c47f3873df.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andreas Larsson <andreas@gaisler.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-10-29 18:11:47 +00:00
#include <linux/shmem_fs.h>
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
#include <linux/types.h>
mm: update architecture and driver code to use vm_flags_t In future we intend to change the vm_flags_t type, so it isn't correct for architecture and driver code to assume it is unsigned long. Correct this assumption across the board. Overall, this patch does not introduce any functional change. Link: https://lkml.kernel.org/r/b6eb1894abc5555ece80bb08af5c022ef780c8bc.1750274467.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64] Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <kees@kernel.org> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-06-18 20:42:54 +01:00
static inline vm_flags_t arch_calc_vm_prot_bits(unsigned long prot,
arm64: convert protection key into vm_flags and pgprot values Modify arch_calc_vm_prot_bits() and vm_get_page_prot() such that the pkey value is set in the vm_flags and then into the pgprot value. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20240822151113.1479789-15-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-08-22 16:10:57 +01:00
unsigned long pkey)
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
{
mm: update architecture and driver code to use vm_flags_t In future we intend to change the vm_flags_t type, so it isn't correct for architecture and driver code to assume it is unsigned long. Correct this assumption across the board. Overall, this patch does not introduce any functional change. Link: https://lkml.kernel.org/r/b6eb1894abc5555ece80bb08af5c022ef780c8bc.1750274467.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64] Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <kees@kernel.org> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-06-18 20:42:54 +01:00
vm_flags_t ret = 0;
arm64: mte: Add PROT_MTE support to mmap() and mprotect() To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-11-27 10:00:27 +00:00
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
if (system_supports_bti() && (prot & PROT_BTI))
arm64: mte: Add PROT_MTE support to mmap() and mprotect() To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-11-27 10:00:27 +00:00
ret |= VM_ARM64_BTI;
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
arm64: mte: Add PROT_MTE support to mmap() and mprotect() To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-11-27 10:00:27 +00:00
if (system_supports_mte() && (prot & PROT_MTE))
ret |= VM_MTE;
arm64: convert protection key into vm_flags and pgprot values Modify arch_calc_vm_prot_bits() and vm_get_page_prot() such that the pkey value is set in the vm_flags and then into the pgprot value. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20240822151113.1479789-15-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-08-22 16:10:57 +01:00
#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
arm64: mte: Add PROT_MTE support to mmap() and mprotect() To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-11-27 10:00:27 +00:00
return ret;
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
}
#define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)
mm: update architecture and driver code to use vm_flags_t In future we intend to change the vm_flags_t type, so it isn't correct for architecture and driver code to assume it is unsigned long. Correct this assumption across the board. Overall, this patch does not introduce any functional change. Link: https://lkml.kernel.org/r/b6eb1894abc5555ece80bb08af5c022ef780c8bc.1750274467.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64] Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <kees@kernel.org> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-06-18 20:42:54 +01:00
static inline vm_flags_t arch_calc_vm_flag_bits(struct file *file,
unsigned long flags)
arm64: mte: Add PROT_MTE support to mmap() and mprotect() To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-11-27 10:00:27 +00:00
{
/*
* 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).
*/
arm64 updates for 6.13: * Support for running Linux in a protected VM under the Arm Confidential Compute Architecture (CCA) * Guarded Control Stack user-space support. Current patches follow the x86 ABI of implicitly creating a shadow stack on clone(). Subsequent patches (already on the list) will add support for clone3() allowing finer-grained control of the shadow stack size and placement from libc * AT_HWCAP3 support (not running out of HWCAP2 bits yet but we are getting close with the upcoming dpISA support) * Other arch features: - In-kernel use of the memcpy instructions, FEAT_MOPS (previously only exposed to user; uaccess support not merged yet) - MTE: hugetlbfs support and the corresponding kselftests - Optimise CRC32 using the PMULL instructions - Support for FEAT_HAFT enabling ARCH_HAS_NONLEAF_PMD_YOUNG - Optimise the kernel TLB flushing to use the range operations - POE/pkey (permission overlays): further cleanups after bringing the signal handler in line with the x86 behaviour for 6.12 * arm64 perf updates: - Support for the NXP i.MX91 PMU in the existing IMX driver - Support for Ampere SoCs in the Designware PCIe PMU driver - Support for Marvell's 'PEM' PCIe PMU present in the 'Odyssey' SoC - Support for Samsung's 'Mongoose' CPU PMU - Support for PMUv3.9 finer-grained userspace counter access control - Switch back to platform_driver::remove() now that it returns 'void' - Add some missing events for the CXL PMU driver * Miscellaneous arm64 fixes/cleanups: - Page table accessors cleanup: type updates, drop unused macros, reorganise arch_make_huge_pte() and clean up pte_mkcont(), sanity check addresses before runtime P4D/PUD folding - Command line override for ID_AA64MMFR0_EL1.ECV (advertising the FEAT_ECV for the generic timers) allowing Linux to boot with firmware deployments that don't set SCTLR_EL3.ECVEn - ACPI/arm64: tighten the check for the array of platform timer structures and adjust the error handling procedure in gtdt_parse_timer_block() - Optimise the cache flush for the uprobes xol slot (skip if no change) and other uprobes/kprobes cleanups - Fix the context switching of tpidrro_el0 when kpti is enabled - Dynamic shadow call stack fixes - Sysreg updates - Various arm64 kselftest improvements -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE5RElWfyWxS+3PLO2a9axLQDIXvEFAmc5POIACgkQa9axLQDI XvEDYA//a3eeNkgMuGdnSCVcLz+zy+oNwAwboG/4X1DqL8jiCbI4npwugPx95RIA YZOUvo9T2aL3OyefpUHll4gFHqx9OwoZIig2F70TEUmlPsGUbh0KBkdfQF3xZPdl EwV0kHSGEqMWMBwsGJGwgCYrUaf1MUQzh1GBl7VJ2ts5XsJBaBeOyKkysij26wtZ V+aHq2IUx7qQS7+HC/4P6IoHxKziFcsCMovaKaynP4cw9xXBQbDMcNlHEwndOMyk pu2zrv7GG0j3KQuVP/2Alf5FKhmI0GVGP/6Nc/zsOmw96w8Kf7HfzEtkHawr2aRq rqg/c9ivzDn1p+fUBo4ZYtrRk4IAY+yKu6hdzdLTP5+bQrBTWTO9rjQVBm9FAGYT sCdEj1NqzvExvNHD7X6ut/GJ05lmce3K+qeSXSEysN9gqiT3eomYWMXrD2V2lxzb rIDDcb/icfaqjt14Mksh19r/rzNeq7noj9CGSmcqw0BHZfHzl38Lai6pdfYzCNyn vCM/c4c1D/WWX8/lifO1JZVbhDk1jy82Iphg2KEhL8iKPxDsKBBZLmYuU1oa7tMo WryGAz9+GQwd+W9chFuaOEtMnzvW2scEJ5Eb2fEf0Qj0aEurkL+C9dZR6o1GN77V DBUxtU628Ef4PJJGfbNCwZzdd8UPYG3a/mKfQQ3dz0oz2LySlW4= =wDot -----END PGP SIGNATURE----- Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Support for running Linux in a protected VM under the Arm Confidential Compute Architecture (CCA) - Guarded Control Stack user-space support. Current patches follow the x86 ABI of implicitly creating a shadow stack on clone(). Subsequent patches (already on the list) will add support for clone3() allowing finer-grained control of the shadow stack size and placement from libc - AT_HWCAP3 support (not running out of HWCAP2 bits yet but we are getting close with the upcoming dpISA support) - Other arch features: - In-kernel use of the memcpy instructions, FEAT_MOPS (previously only exposed to user; uaccess support not merged yet) - MTE: hugetlbfs support and the corresponding kselftests - Optimise CRC32 using the PMULL instructions - Support for FEAT_HAFT enabling ARCH_HAS_NONLEAF_PMD_YOUNG - Optimise the kernel TLB flushing to use the range operations - POE/pkey (permission overlays): further cleanups after bringing the signal handler in line with the x86 behaviour for 6.12 - arm64 perf updates: - Support for the NXP i.MX91 PMU in the existing IMX driver - Support for Ampere SoCs in the Designware PCIe PMU driver - Support for Marvell's 'PEM' PCIe PMU present in the 'Odyssey' SoC - Support for Samsung's 'Mongoose' CPU PMU - Support for PMUv3.9 finer-grained userspace counter access control - Switch back to platform_driver::remove() now that it returns 'void' - Add some missing events for the CXL PMU driver - Miscellaneous arm64 fixes/cleanups: - Page table accessors cleanup: type updates, drop unused macros, reorganise arch_make_huge_pte() and clean up pte_mkcont(), sanity check addresses before runtime P4D/PUD folding - Command line override for ID_AA64MMFR0_EL1.ECV (advertising the FEAT_ECV for the generic timers) allowing Linux to boot with firmware deployments that don't set SCTLR_EL3.ECVEn - ACPI/arm64: tighten the check for the array of platform timer structures and adjust the error handling procedure in gtdt_parse_timer_block() - Optimise the cache flush for the uprobes xol slot (skip if no change) and other uprobes/kprobes cleanups - Fix the context switching of tpidrro_el0 when kpti is enabled - Dynamic shadow call stack fixes - Sysreg updates - Various arm64 kselftest improvements * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (168 commits) arm64: tls: Fix context-switching of tpidrro_el0 when kpti is enabled kselftest/arm64: Try harder to generate different keys during PAC tests kselftest/arm64: Don't leak pipe fds in pac.exec_sign_all() arm64/ptrace: Clarify documentation of VL configuration via ptrace kselftest/arm64: Corrupt P0 in the irritator when testing SSVE acpi/arm64: remove unnecessary cast arm64/mm: Change protval as 'pteval_t' in map_range() kselftest/arm64: Fix missing printf() argument in gcs/gcs-stress.c kselftest/arm64: Add FPMR coverage to fp-ptrace kselftest/arm64: Expand the set of ZA writes fp-ptrace does kselftets/arm64: Use flag bits for features in fp-ptrace assembler code kselftest/arm64: Enable build of PAC tests with LLVM=1 kselftest/arm64: Check that SVCR is 0 in signal handlers selftests/mm: Fix unused function warning for aarch64_write_signal_pkey() kselftest/arm64: Fix printf() compiler warnings in the arm64 syscall-abi.c tests kselftest/arm64: Fix printf() warning in the arm64 MTE prctl() test kselftest/arm64: Fix printf() compiler warnings in the arm64 fp tests kselftest/arm64: Fix build with stricter assemblers arm64/scs: Drop unused prototype __pi_scs_patch_vmlinux() arm64/scs: Deal with 64-bit relative offsets in FDE frames ...
2024-11-18 18:10:37 -08:00
if (system_supports_mte()) {
if (flags & (MAP_ANONYMOUS | MAP_HUGETLB))
return VM_MTE_ALLOWED;
arm64: mte: set VM_MTE_ALLOWED for hugetlbfs at correct place The commit 5de195060b2e ("mm: resolve faulty mmap_region() error path behaviour") moved vm flags validation before fop->mmap for file mappings. But when commit 25c17c4b55de ("hugetlb: arm64: add mte support") was rebased on top of it, the hugetlbfs part was missed. Mmapping hugetlbfs file may not have MAP_HUGETLB set. Fixes: 25c17c4b55de ("hugetlb: arm64: add mte support") Signed-off-by: Yang Shi <yang@os.amperecomputing.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20241119200914.1145249-1-yang@os.amperecomputing.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-19 12:09:14 -08:00
if (shmem_file(file) || is_file_hugepages(file))
arm64 updates for 6.13: * Support for running Linux in a protected VM under the Arm Confidential Compute Architecture (CCA) * Guarded Control Stack user-space support. Current patches follow the x86 ABI of implicitly creating a shadow stack on clone(). Subsequent patches (already on the list) will add support for clone3() allowing finer-grained control of the shadow stack size and placement from libc * AT_HWCAP3 support (not running out of HWCAP2 bits yet but we are getting close with the upcoming dpISA support) * Other arch features: - In-kernel use of the memcpy instructions, FEAT_MOPS (previously only exposed to user; uaccess support not merged yet) - MTE: hugetlbfs support and the corresponding kselftests - Optimise CRC32 using the PMULL instructions - Support for FEAT_HAFT enabling ARCH_HAS_NONLEAF_PMD_YOUNG - Optimise the kernel TLB flushing to use the range operations - POE/pkey (permission overlays): further cleanups after bringing the signal handler in line with the x86 behaviour for 6.12 * arm64 perf updates: - Support for the NXP i.MX91 PMU in the existing IMX driver - Support for Ampere SoCs in the Designware PCIe PMU driver - Support for Marvell's 'PEM' PCIe PMU present in the 'Odyssey' SoC - Support for Samsung's 'Mongoose' CPU PMU - Support for PMUv3.9 finer-grained userspace counter access control - Switch back to platform_driver::remove() now that it returns 'void' - Add some missing events for the CXL PMU driver * Miscellaneous arm64 fixes/cleanups: - Page table accessors cleanup: type updates, drop unused macros, reorganise arch_make_huge_pte() and clean up pte_mkcont(), sanity check addresses before runtime P4D/PUD folding - Command line override for ID_AA64MMFR0_EL1.ECV (advertising the FEAT_ECV for the generic timers) allowing Linux to boot with firmware deployments that don't set SCTLR_EL3.ECVEn - ACPI/arm64: tighten the check for the array of platform timer structures and adjust the error handling procedure in gtdt_parse_timer_block() - Optimise the cache flush for the uprobes xol slot (skip if no change) and other uprobes/kprobes cleanups - Fix the context switching of tpidrro_el0 when kpti is enabled - Dynamic shadow call stack fixes - Sysreg updates - Various arm64 kselftest improvements -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE5RElWfyWxS+3PLO2a9axLQDIXvEFAmc5POIACgkQa9axLQDI XvEDYA//a3eeNkgMuGdnSCVcLz+zy+oNwAwboG/4X1DqL8jiCbI4npwugPx95RIA YZOUvo9T2aL3OyefpUHll4gFHqx9OwoZIig2F70TEUmlPsGUbh0KBkdfQF3xZPdl EwV0kHSGEqMWMBwsGJGwgCYrUaf1MUQzh1GBl7VJ2ts5XsJBaBeOyKkysij26wtZ V+aHq2IUx7qQS7+HC/4P6IoHxKziFcsCMovaKaynP4cw9xXBQbDMcNlHEwndOMyk pu2zrv7GG0j3KQuVP/2Alf5FKhmI0GVGP/6Nc/zsOmw96w8Kf7HfzEtkHawr2aRq rqg/c9ivzDn1p+fUBo4ZYtrRk4IAY+yKu6hdzdLTP5+bQrBTWTO9rjQVBm9FAGYT sCdEj1NqzvExvNHD7X6ut/GJ05lmce3K+qeSXSEysN9gqiT3eomYWMXrD2V2lxzb rIDDcb/icfaqjt14Mksh19r/rzNeq7noj9CGSmcqw0BHZfHzl38Lai6pdfYzCNyn vCM/c4c1D/WWX8/lifO1JZVbhDk1jy82Iphg2KEhL8iKPxDsKBBZLmYuU1oa7tMo WryGAz9+GQwd+W9chFuaOEtMnzvW2scEJ5Eb2fEf0Qj0aEurkL+C9dZR6o1GN77V DBUxtU628Ef4PJJGfbNCwZzdd8UPYG3a/mKfQQ3dz0oz2LySlW4= =wDot -----END PGP SIGNATURE----- Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Support for running Linux in a protected VM under the Arm Confidential Compute Architecture (CCA) - Guarded Control Stack user-space support. Current patches follow the x86 ABI of implicitly creating a shadow stack on clone(). Subsequent patches (already on the list) will add support for clone3() allowing finer-grained control of the shadow stack size and placement from libc - AT_HWCAP3 support (not running out of HWCAP2 bits yet but we are getting close with the upcoming dpISA support) - Other arch features: - In-kernel use of the memcpy instructions, FEAT_MOPS (previously only exposed to user; uaccess support not merged yet) - MTE: hugetlbfs support and the corresponding kselftests - Optimise CRC32 using the PMULL instructions - Support for FEAT_HAFT enabling ARCH_HAS_NONLEAF_PMD_YOUNG - Optimise the kernel TLB flushing to use the range operations - POE/pkey (permission overlays): further cleanups after bringing the signal handler in line with the x86 behaviour for 6.12 - arm64 perf updates: - Support for the NXP i.MX91 PMU in the existing IMX driver - Support for Ampere SoCs in the Designware PCIe PMU driver - Support for Marvell's 'PEM' PCIe PMU present in the 'Odyssey' SoC - Support for Samsung's 'Mongoose' CPU PMU - Support for PMUv3.9 finer-grained userspace counter access control - Switch back to platform_driver::remove() now that it returns 'void' - Add some missing events for the CXL PMU driver - Miscellaneous arm64 fixes/cleanups: - Page table accessors cleanup: type updates, drop unused macros, reorganise arch_make_huge_pte() and clean up pte_mkcont(), sanity check addresses before runtime P4D/PUD folding - Command line override for ID_AA64MMFR0_EL1.ECV (advertising the FEAT_ECV for the generic timers) allowing Linux to boot with firmware deployments that don't set SCTLR_EL3.ECVEn - ACPI/arm64: tighten the check for the array of platform timer structures and adjust the error handling procedure in gtdt_parse_timer_block() - Optimise the cache flush for the uprobes xol slot (skip if no change) and other uprobes/kprobes cleanups - Fix the context switching of tpidrro_el0 when kpti is enabled - Dynamic shadow call stack fixes - Sysreg updates - Various arm64 kselftest improvements * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (168 commits) arm64: tls: Fix context-switching of tpidrro_el0 when kpti is enabled kselftest/arm64: Try harder to generate different keys during PAC tests kselftest/arm64: Don't leak pipe fds in pac.exec_sign_all() arm64/ptrace: Clarify documentation of VL configuration via ptrace kselftest/arm64: Corrupt P0 in the irritator when testing SSVE acpi/arm64: remove unnecessary cast arm64/mm: Change protval as 'pteval_t' in map_range() kselftest/arm64: Fix missing printf() argument in gcs/gcs-stress.c kselftest/arm64: Add FPMR coverage to fp-ptrace kselftest/arm64: Expand the set of ZA writes fp-ptrace does kselftets/arm64: Use flag bits for features in fp-ptrace assembler code kselftest/arm64: Enable build of PAC tests with LLVM=1 kselftest/arm64: Check that SVCR is 0 in signal handlers selftests/mm: Fix unused function warning for aarch64_write_signal_pkey() kselftest/arm64: Fix printf() compiler warnings in the arm64 syscall-abi.c tests kselftest/arm64: Fix printf() warning in the arm64 MTE prctl() test kselftest/arm64: Fix printf() compiler warnings in the arm64 fp tests kselftest/arm64: Fix build with stricter assemblers arm64/scs: Drop unused prototype __pi_scs_patch_vmlinux() arm64/scs: Deal with 64-bit relative offsets in FDE frames ...
2024-11-18 18:10:37 -08:00
return VM_MTE_ALLOWED;
}
arm64: mte: Add PROT_MTE support to mmap() and mprotect() To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-11-27 10:00:27 +00:00
return 0;
}
mm: refactor arch_calc_vm_flag_bits() and arm64 MTE handling Currently MTE is permitted in two circumstances (desiring to use MTE having been specified by the VM_MTE flag) - where MAP_ANONYMOUS is specified, as checked by arch_calc_vm_flag_bits() and actualised by setting the VM_MTE_ALLOWED flag, or if the file backing the mapping is shmem, in which case we set VM_MTE_ALLOWED in shmem_mmap() when the mmap hook is activated in mmap_region(). The function that checks that, if VM_MTE is set, VM_MTE_ALLOWED is also set is the arm64 implementation of arch_validate_flags(). Unfortunately, we intend to refactor mmap_region() to perform this check earlier, meaning that in the case of a shmem backing we will not have invoked shmem_mmap() yet, causing the mapping to fail spuriously. It is inappropriate to set this architecture-specific flag in general mm code anyway, so a sensible resolution of this issue is to instead move the check somewhere else. We resolve this by setting VM_MTE_ALLOWED much earlier in do_mmap(), via the arch_calc_vm_flag_bits() call. This is an appropriate place to do this as we already check for the MAP_ANONYMOUS case here, and the shmem file case is simply a variant of the same idea - we permit RAM-backed memory. This requires a modification to the arch_calc_vm_flag_bits() signature to pass in a pointer to the struct file associated with the mapping, however this is not too egregious as this is only used by two architectures anyway - arm64 and parisc. So this patch performs this adjustment and removes the unnecessary assignment of VM_MTE_ALLOWED in shmem_mmap(). [akpm@linux-foundation.org: fix whitespace, per Catalin] Link: https://lkml.kernel.org/r/ec251b20ba1964fb64cf1607d2ad80c47f3873df.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andreas Larsson <andreas@gaisler.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-10-29 18:11:47 +00:00
#define arch_calc_vm_flag_bits(file, flags) arch_calc_vm_flag_bits(file, flags)
arm64: mte: Add PROT_MTE support to mmap() and mprotect() To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-11-27 10:00:27 +00:00
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
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;
arm64: mte: Add PROT_MTE support to mmap() and mprotect() To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-11-27 10:00:27 +00:00
if (system_supports_mte())
supported |= PROT_MTE;
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
return (prot & ~supported) == 0;
}
#define arch_validate_prot(prot, addr) arch_validate_prot(prot, addr)
mm: update architecture and driver code to use vm_flags_t In future we intend to change the vm_flags_t type, so it isn't correct for architecture and driver code to assume it is unsigned long. Correct this assumption across the board. Overall, this patch does not introduce any functional change. Link: https://lkml.kernel.org/r/b6eb1894abc5555ece80bb08af5c022ef780c8bc.1750274467.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64] Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <kees@kernel.org> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-06-18 20:42:54 +01:00
static inline bool arch_validate_flags(vm_flags_t vm_flags)
arm64: mte: Validate the PROT_MTE request via arch_validate_flags() Make use of the newly introduced arch_validate_flags() hook to sanity-check the PROT_MTE request passed to mmap() and mprotect(). If the mapping does not support MTE, these syscalls will return -EINVAL. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-08-09 15:48:46 +01:00
{
arm64/mm: Restructure arch_validate_flags() for extensibility Currently arch_validate_flags() is written in a very non-extensible fashion, returning immediately if MTE is not supported and writing the MTE check as a direct return. Since we will want to add more checks for GCS refactor the existing code to be more extensible, no functional change intended. Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-3-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-01 23:58:42 +01:00
if (system_supports_mte()) {
/*
* only allow VM_MTE if VM_MTE_ALLOWED has been set
* previously
*/
if ((vm_flags & VM_MTE) && !(vm_flags & VM_MTE_ALLOWED))
return false;
}
arm64/mm: Map pages for guarded control stack Map pages flagged as being part of a GCS as such rather than using the full set of generic VM flags. This is done using a conditional rather than extending the size of protection_map since that would make for a very sparse array. Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-15-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-01 23:58:54 +01:00
if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) {
/* An executable GCS isn't a good idea. */
if (vm_flags & VM_EXEC)
return false;
/* The memory management core should prevent this */
VM_WARN_ON(vm_flags & VM_SHARED);
}
arm64/mm: Restructure arch_validate_flags() for extensibility Currently arch_validate_flags() is written in a very non-extensible fashion, returning immediately if MTE is not supported and writing the MTE check as a direct return. Since we will want to add more checks for GCS refactor the existing code to be more extensible, no functional change intended. Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-3-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-01 23:58:42 +01:00
return true;
arm64: mte: Validate the PROT_MTE request via arch_validate_flags() Make use of the newly introduced arch_validate_flags() hook to sanity-check the PROT_MTE request passed to mmap() and mprotect(). If the mapping does not support MTE, these syscalls will return -EINVAL. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org>
2019-08-09 15:48:46 +01:00
}
#define arch_validate_flags(vm_flags) arch_validate_flags(vm_flags)
arm64: vDSO: Wire up getrandom() vDSO implementation Hook up the generic vDSO implementation to the aarch64 vDSO data page. The _vdso_rng_data required data is placed within the _vdso_data vvar page, by using a offset larger than the vdso_data. The vDSO function requires a ChaCha20 implementation that does not write to the stack, and that can do an entire ChaCha20 permutation. The one provided uses NEON on the permute operation, with a fallback to the syscall for chips that do not support AdvSIMD. This also passes the vdso_test_chacha test along with vdso_test_getrandom. The vdso_test_getrandom bench-single result on Neoverse-N1 shows: vdso: 25000000 times in 0.783884250 seconds libc: 25000000 times in 8.780275399 seconds syscall: 25000000 times in 8.786581518 seconds A small fixup to arch/arm64/include/asm/mman.h was required to avoid pulling kernel code into the vDSO, similar to what's already done in arch/arm64/include/asm/rwonce.h. Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2024-09-03 12:09:17 +00:00
#endif /* !BUILD_VDSO */
arm64: Basic Branch Target Identification support This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 16:50:45 +00:00
#endif /* ! __ASM_MMAN_H__ */
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