diff options
| author | Catalin Marinas <[email protected]> | 2019-08-09 15:48:46 +0100 |
|---|---|---|
| committer | Catalin Marinas <[email protected]> | 2020-09-04 12:46:07 +0100 |
| commit | 0042090548740921951f31fc0c20dcdb96638cb0 (patch) | |
| tree | 70707f0b5fb69991e6bf51d66dd60ae6bd0afbc4 | |
| parent | c462ac288f2c97e0c1d9ff6a65955317e799f958 (diff) | |
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 <[email protected]>
Cc: Will Deacon <[email protected]>
| -rw-r--r-- | arch/arm64/include/asm/mman.h | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h index b01051be7750..e3e28f7daf62 100644 --- a/arch/arm64/include/asm/mman.h +++ b/arch/arm64/include/asm/mman.h @@ -49,8 +49,10 @@ static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags) * register (1) as VM_MTE in the vma->vm_flags and (2) as * VM_MTE_ALLOWED. Note that the latter can only be set during the * mmap() call since mprotect() does not accept MAP_* flags. + * Checking for VM_MTE only is sufficient since arch_validate_flags() + * does not permit (VM_MTE & !VM_MTE_ALLOWED). */ - if ((vm_flags & VM_MTE) && (vm_flags & VM_MTE_ALLOWED)) + if (vm_flags & VM_MTE) prot |= PTE_ATTRINDX(MT_NORMAL_TAGGED); return __pgprot(prot); @@ -72,4 +74,14 @@ 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) +{ + 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 /* ! __ASM_MMAN_H__ */ |