aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390
diff options
context:
space:
mode:
authorDmitry Safonov <dima@arista.com>2020-12-14 19:08:25 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-12-15 12:13:41 -0800
commit871402e05b24cb56bc69df47cff960d0e0d24267 (patch)
treef8235ea5b089ed3c9def2e9c6ed2df51d205e8d3 /arch/s390
parent73d5e06299195f4df82832cfc4a3a0c574c1e473 (diff)
mm: forbid splitting special mappings
Don't allow splitting of vm_special_mapping's. It affects vdso/vvar areas. Uprobes have only one page in xol_area so they aren't affected. Those restrictions were enforced by checks in .mremap() callbacks. Restrict resizing with generic .split() callback. Link: https://lkml.kernel.org/r/20201013013416.390574-7-dima@arista.com Signed-off-by: Dmitry Safonov <dima@arista.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/s390')
-rw-r--r--arch/s390/kernel/vdso.c11
1 files changed, 1 insertions, 10 deletions
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
index f9da5b149141..6c9ec9521203 100644
--- a/arch/s390/kernel/vdso.c
+++ b/arch/s390/kernel/vdso.c
@@ -61,17 +61,8 @@ static vm_fault_t vdso_fault(const struct vm_special_mapping *sm,
static int vdso_mremap(const struct vm_special_mapping *sm,
struct vm_area_struct *vma)
{
- unsigned long vdso_pages;
-
- vdso_pages = vdso64_pages;
-
- if ((vdso_pages << PAGE_SHIFT) != vma->vm_end - vma->vm_start)
- return -EINVAL;
-
- if (WARN_ON_ONCE(current->mm != vma->vm_mm))
- return -EFAULT;
-
current->mm->context.vdso_base = vma->vm_start;
+
return 0;
}

Privacy Policy