diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2016-06-13 16:00:48 +0200 |
|---|---|---|
| committer | Christoffer Dall <christoffer.dall@linaro.org> | 2016-06-29 14:01:34 +0200 |
| commit | 5900270550cbb8a272bfc248b69531cd44dcf0d5 (patch) | |
| tree | 9683a4f7757d6e45d58302b4d950ac3df703dbad | |
| parent | arm/arm64: KVM: Enforce HYP read-only mapping of the kernel's rodata section (diff) | |
| download | linux-5900270550cbb8a272bfc248b69531cd44dcf0d5.tar.xz linux-5900270550cbb8a272bfc248b69531cd44dcf0d5.zip | |
arm/arm64: KVM: Map the HYP text as read-only
There should be no reason for mapping the HYP text read/write.
As such, let's have a new set of flags (PAGE_HYP_EXEC) that allows
execution, but makes the page as read-only, and update the two call
sites that deal with mapping code.
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/arm/kvm/mmu.c | 6 | ||||
| -rw-r--r-- | arch/arm64/include/asm/pgtable-prot.h | 1 |
4 files changed, 6 insertions, 4 deletions
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index f3320870a90a..7487bf9f97dc 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_EXEC _MOD_PROT(pgprot_kernel, L_PTE_HYP | L_PTE_RDONLY) #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) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index b30897679e53..c74483fc39f2 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -1293,7 +1293,7 @@ static int init_hyp_mode(void) * Map the Hyp-code called directly from the host */ err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), - kvm_ksym_ref(__hyp_text_end), PAGE_HYP); + kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); if (err) { kvm_err("Cannot map world-switch code\n"); goto out_err; diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 49cb5ccf6c23..679608fa1666 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -1733,7 +1733,7 @@ int kvm_mmu_init(void) err = __create_hyp_mappings(boot_hyp_pgd, hyp_idmap_start, hyp_idmap_end, __phys_to_pfn(hyp_idmap_start), - PAGE_HYP); + PAGE_HYP_EXEC); if (err) { kvm_err("Failed to idmap %lx-%lx\n", @@ -1756,7 +1756,7 @@ int kvm_mmu_init(void) err = __create_hyp_mappings(boot_hyp_pgd, TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE, __phys_to_pfn(hyp_idmap_start), - PAGE_HYP); + PAGE_HYP_EXEC); if (err) { kvm_err("Failed to map trampoline @%lx into boot HYP pgd\n", TRAMPOLINE_VA); @@ -1767,7 +1767,7 @@ int kvm_mmu_init(void) err = __create_hyp_mappings(hyp_pgd, TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE, __phys_to_pfn(hyp_idmap_start), - PAGE_HYP); + PAGE_HYP_EXEC); if (err) { kvm_err("Failed to map trampoline @%lx into runtime HYP pgd\n", TRAMPOLINE_VA); diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index 88db58cac587..380204847c20 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_EXEC __pgprot(_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY) #define PAGE_HYP_RO __pgprot(_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY | PTE_HYP_XN) #define PAGE_HYP_DEVICE __pgprot(PROT_DEVICE_nGnRE | PTE_HYP) |