Commit cca98e9f authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Linus Torvalds

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.
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Mark Rutland <mark.rutland@arm.com>.
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-20-hch@lst.deSigned-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d4efd79a
...@@ -407,6 +407,9 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd) ...@@ -407,6 +407,9 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd)
#define __pgprot_modify(prot,mask,bits) \ #define __pgprot_modify(prot,mask,bits) \
__pgprot((pgprot_val(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. * Mark the prot value as uncacheable and unbufferable.
*/ */
......
...@@ -282,6 +282,12 @@ typedef struct pgprot { pgprotval_t pgprot; } pgprot_t; ...@@ -282,6 +282,12 @@ typedef struct pgprot { pgprotval_t pgprot; } pgprot_t;
typedef struct { pgdval_t pgd; } pgd_t; 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 #ifdef CONFIG_X86_PAE
/* /*
......
...@@ -491,6 +491,10 @@ static inline int arch_unmap_one(struct mm_struct *mm, ...@@ -491,6 +491,10 @@ static inline int arch_unmap_one(struct mm_struct *mm,
#define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address) #define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address)
#endif #endif
#ifndef pgprot_nx
#define pgprot_nx(prot) (prot)
#endif
#ifndef pgprot_noncached #ifndef pgprot_noncached
#define pgprot_noncached(prot) (prot) #define pgprot_noncached(prot) (prot)
#endif #endif
......
...@@ -2391,7 +2391,7 @@ void *vmap(struct page **pages, unsigned int count, ...@@ -2391,7 +2391,7 @@ void *vmap(struct page **pages, unsigned int count,
if (!area) if (!area)
return NULL; 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) { pages) < 0) {
vunmap(area->addr); vunmap(area->addr);
return NULL; return NULL;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment