The patch titled
Subject: mm: enforce that vmap can't map pages executable
has been added to the -mm tree. Its filename is
mm-enforce-that-vmap-cant-map-pages-executable.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-enforce-that-vmap-cant-map-pages-executable.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-enforce-that-vmap-cant-map-pages-executable.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Christoph Hellwig <hch@xxxxxx>
Subject: mm: enforce that vmap can't map pages executable
To help enforcing the W^X protection don't allow remapping existing pages
as executable.
x86 bits from Peter Zijlstra, arm64 bits from Mark Rutland.
Link: http://lkml.kernel.org/r/20200414131348.444715-20-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>.
Cc: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Gao Xiang <xiang@xxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: "K. Y. Srinivasan" <kys@xxxxxxxxxxxxx>
Cc: Laura Abbott <labbott@xxxxxxxxxx>
Cc: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Nitin Gupta <ngupta@xxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Cc: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>
Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
Cc: Wei Liu <wei.liu@xxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/arm64/include/asm/pgtable.h | 3 +++
arch/x86/include/asm/pgtable_types.h | 6 ++++++
include/asm-generic/pgtable.h | 4 ++++
mm/vmalloc.c | 2 +-
4 files changed, 14 insertions(+), 1 deletion(-)
--- a/arch/arm64/include/asm/pgtable.h~mm-enforce-that-vmap-cant-map-pages-executable
+++ a/arch/arm64/include/asm/pgtable.h
@@ -415,6 +415,9 @@ static inline pmd_t pmd_mkdevmap(pmd_t p
#define __pgprot_modify(prot,mask,bits) \
__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
+#define pgprot_nx(prot) \
+ __pgprot_modify(prot, 0, PTE_PXN)
+
/*
* Mark the prot value as uncacheable and unbufferable.
*/
--- a/arch/x86/include/asm/pgtable_types.h~mm-enforce-that-vmap-cant-map-pages-executable
+++ a/arch/x86/include/asm/pgtable_types.h
@@ -282,6 +282,12 @@ typedef struct pgprot { pgprotval_t pgpr
typedef struct { pgdval_t pgd; } pgd_t;
+static inline pgprot_t pgprot_nx(pgprot_t prot)
+{
+ return __pgprot(pgprot_val(prot) | _PAGE_NX);
+}
+#define pgprot_nx pgprot_nx
+
#ifdef CONFIG_X86_PAE
/*
--- a/include/asm-generic/pgtable.h~mm-enforce-that-vmap-cant-map-pages-executable
+++ a/include/asm-generic/pgtable.h
@@ -491,6 +491,10 @@ static inline int arch_unmap_one(struct
#define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address)
#endif
+#ifndef pgprot_nx
+#define pgprot_nx(prot) (prot)
+#endif
+
#ifndef pgprot_noncached
#define pgprot_noncached(prot) (prot)
#endif
--- a/mm/vmalloc.c~mm-enforce-that-vmap-cant-map-pages-executable
+++ a/mm/vmalloc.c
@@ -2390,7 +2390,7 @@ void *vmap(struct page **pages, unsigned
if (!area)
return NULL;
- if (map_kernel_range((unsigned long)area->addr, size, prot,
+ if (map_kernel_range((unsigned long)area->addr, size, pgprot_nx(prot),
pages) < 0) {
vunmap(area->addr);
return NULL;
_
Patches currently in -mm which might be from hch@xxxxxx are
x86-hyperv-use-vmalloc_exec-for-the-hypercall-page.patch
x86-fix-vmap-arguments-in-map_irq_stack.patch
staging-android-ion-use-vmap-instead-of-vm_map_ram.patch
staging-media-ipu3-use-vmap-instead-of-reimplementing-it.patch
dma-mapping-use-vmap-insted-of-reimplementing-it.patch
powerpc-add-an-ioremap_phb-helper.patch
powerpc-remove-__ioremap_at-and-__iounmap_at.patch
mm-remove-__get_vm_area.patch
mm-unexport-unmap_kernel_range_noflush.patch
mm-rename-config_pgtable_mapping-to-config_zsmalloc_pgtable_mapping.patch
mm-only-allow-page-table-mappings-for-built-in-zsmalloc.patch
mm-pass-addr-as-unsigned-long-to-vb_free.patch
mm-remove-vmap_page_range_noflush-and-vunmap_page_range.patch
mm-rename-vmap_page_range-to-map_kernel_range.patch
mm-dont-return-the-number-of-pages-from-map_kernel_range_noflush.patch
mm-remove-map_vm_range.patch
mm-remove-unmap_vmap_area.patch
mm-remove-the-prot-argument-from-vm_map_ram.patch
mm-enforce-that-vmap-cant-map-pages-executable.patch
gpu-drm-remove-the-powerpc-hack-in-drm_legacy_sg_alloc.patch
mm-remove-the-pgprot-argument-to-__vmalloc.patch
mm-remove-the-prot-argument-to-__vmalloc_node.patch
mm-remove-both-instances-of-__vmalloc_node_flags.patch
mm-remove-__vmalloc_node_flags_caller.patch
mm-switch-the-test_vmalloc-module-to-use-__vmalloc_node.patch
mm-remove-vmalloc_user_node_flags.patch
arm64-use-__vmalloc_node-in-arch_alloc_vmap_stack.patch
powerpc-use-__vmalloc_node-in-alloc_vm_stack.patch
s390-use-__vmalloc_node-in-stack_alloc.patch
