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| author | Marc Zyngier <marc.zyngier@arm.com> | 2016-06-13 16:00:47 +0200 |
|---|---|---|
| committer | Christoffer Dall <christoffer.dall@linaro.org> | 2016-06-29 13:59:14 +0200 |
| commit | 74a6b8885f7026e33f8a4776b7ac17c76b8e5a52 (patch) | |
| tree | 694666822483772f344c336ae04c8ee854d667c3 | |
| parent | arm64: Add PTE_HYP_XN page table flag (diff) | |
| download | linux-74a6b8885f7026e33f8a4776b7ac17c76b8e5a52.tar.xz linux-74a6b8885f7026e33f8a4776b7ac17c76b8e5a52.zip | |
arm/arm64: KVM: Enforce HYP read-only mapping of the kernel's rodata section
In order to be able to use C code in HYP, we're now mapping the kernel's
rodata in HYP. It works absolutely fine, except that we're mapping it RWX,
which is not what it should be.
Add a new HYP_PAGE_RO protection, and pass it as the protection flags
when mapping the rodata section.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| -rw-r--r-- | arch/arm/include/asm/pgtable.h | 1 | ||||
| -rw-r--r-- | arch/arm/kvm/arm.c | 2 | ||||
| -rw-r--r-- | arch/arm64/include/asm/pgtable-prot.h | 1 |
3 files changed, 3 insertions, 1 deletions
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index 348caabb7625..f3320870a90a 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -98,6 +98,7 @@ extern pgprot_t pgprot_s2_device; #define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN) #define PAGE_KERNEL_EXEC pgprot_kernel #define PAGE_HYP _MOD_PROT(pgprot_kernel, L_PTE_HYP) +#define PAGE_HYP_RO _MOD_PROT(pgprot_kernel, L_PTE_HYP | L_PTE_RDONLY | L_PTE_XN) #define PAGE_HYP_DEVICE _MOD_PROT(pgprot_hyp_device, L_PTE_HYP) #define PAGE_S2 _MOD_PROT(pgprot_s2, L_PTE_S2_RDONLY) #define PAGE_S2_DEVICE _MOD_PROT(pgprot_s2_device, L_PTE_S2_RDONLY) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 45dd6df70cdf..b30897679e53 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -1300,7 +1300,7 @@ static int init_hyp_mode(void) } err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), - kvm_ksym_ref(__end_rodata), PAGE_HYP); + kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); if (err) { kvm_err("Cannot map rodata section\n"); goto out_err; diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index 29fcb33ab401..88db58cac587 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -56,6 +56,7 @@ #define PAGE_KERNEL_EXEC_CONT __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE | PTE_CONT) #define PAGE_HYP __pgprot(_PAGE_DEFAULT | PTE_HYP) +#define PAGE_HYP_RO __pgprot(_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY | PTE_HYP_XN) #define PAGE_HYP_DEVICE __pgprot(PROT_DEVICE_nGnRE | PTE_HYP) #define PAGE_S2 __pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_NORMAL) | PTE_S2_RDONLY) |