[PATCH v25 29/30] mm: Update arch_validate_flags() to include vma anonymous
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STALE1996d
SUPERSEDED
From: Yu-cheng Yu <hidden>
Date: 2021-04-15 22:18:55
Also in:
linux-arch, linux-doc, linux-mm, lkml
Subsystem:
arm64 port (aarch64 architecture), memory management, memory mapping, sparc + ultrasparc (sparc/sparc64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Andrew Morton, Liam R. Howlett, Lorenzo Stoakes, "David S. Miller", Andreas Larsson, Linus Torvalds
Revision v25 of 7 in this series.
Revisions (7)
When newer VM flags are being created, such as VM_MTE, it becomes necessary
for mmap/mprotect to verify if certain flags are being applied to an
anonymous VMA.
To solve this, one approach is adding a VM flag to track that MAP_ANONYMOUS
is specified [1], and then using the flag in arch_validate_flags().
Another approach is passing vma_is_anonymous() to arch_validate_flags().
To prepare the introduction of PROT_SHSTK, which creates a shadow stack
mapping and can only be applied to an anonymous VMA, update arch_validate_
flags() to include anonymous VMA information.
[1] commit 9f3419315f3c ("arm64: mte: Add PROT_MTE support to mmap() and mprotect()"),
Signed-off-by: Yu-cheng Yu <redacted>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Kees Cook <redacted>
Cc: Kirill A. Shutemov <redacted>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
---
arch/arm64/include/asm/mman.h | 4 ++--
arch/sparc/include/asm/mman.h | 4 ++--
include/linux/mman.h | 2 +-
mm/mmap.c | 2 +-
mm/mprotect.c | 2 +-
5 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h
index e3e28f7daf62..44add1a09041 100644
--- a/arch/arm64/include/asm/mman.h
+++ b/arch/arm64/include/asm/mman.h@@ -74,7 +74,7 @@ static inline bool arch_validate_prot(unsigned long prot, } #define arch_validate_prot(prot, addr) arch_validate_prot(prot, addr) -static inline bool arch_validate_flags(unsigned long vm_flags) +static inline bool arch_validate_flags(unsigned long vm_flags, bool is_anon) { if (!system_supports_mte()) return true;
@@ -82,6 +82,6 @@ static inline bool arch_validate_flags(unsigned long vm_flags) /* 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) +#define arch_validate_flags(vm_flags, is_anon) arch_validate_flags(vm_flags, is_anon) #endif /* ! __ASM_MMAN_H__ */
diff --git a/arch/sparc/include/asm/mman.h b/arch/sparc/include/asm/mman.h
index 274217e7ed70..4a897c8a3f1a 100644
--- a/arch/sparc/include/asm/mman.h
+++ b/arch/sparc/include/asm/mman.h@@ -60,11 +60,11 @@ static inline int sparc_validate_prot(unsigned long prot, unsigned long addr) return 1; } -#define arch_validate_flags(vm_flags) arch_validate_flags(vm_flags) +#define arch_validate_flags(vm_flags, is_anon) arch_validate_flags(vm_flags, is_anon) /* arch_validate_flags() - Ensure combination of flags is valid for a * VMA. */ -static inline bool arch_validate_flags(unsigned long vm_flags) +static inline bool arch_validate_flags(unsigned long vm_flags, bool is_anon) { /* If ADI is being enabled on this VMA, check for ADI * capability on the platform and ensure VMA is suitable
diff --git a/include/linux/mman.h b/include/linux/mman.h
index 629cefc4ecba..a22ed4495d13 100644
--- a/include/linux/mman.h
+++ b/include/linux/mman.h@@ -114,7 +114,7 @@ static inline bool arch_validate_prot(unsigned long prot, unsigned long addr) * * Returns true if the VM_* flags are valid. */ -static inline bool arch_validate_flags(unsigned long flags) +static inline bool arch_validate_flags(unsigned long flags, bool is_anonymous) { return true; }
diff --git a/mm/mmap.c b/mm/mmap.c
index 7b2992ef8ee0..db849e3ed9d3 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c@@ -1850,7 +1850,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, } /* Allow architectures to sanity-check the vm_flags */ - if (!arch_validate_flags(vma->vm_flags)) { + if (!arch_validate_flags(vma->vm_flags, vma_is_anonymous(vma))) { error = -EINVAL; if (file) goto unmap_and_free_vma;
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 3b2f0d75519f..64378b963548 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c@@ -611,7 +611,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len, } /* Allow architectures to sanity-check the new flags */ - if (!arch_validate_flags(newflags)) { + if (!arch_validate_flags(newflags, vma_is_anonymous(vma))) { error = -EINVAL; goto out; }
--
2.21.0