diff options
| author | Dmitry Safonov <dima@arista.com> | 2020-12-14 19:08:25 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-15 12:13:41 -0800 |
| commit | 871402e05b24cb56bc69df47cff960d0e0d24267 (patch) | |
| tree | f8235ea5b089ed3c9def2e9c6ed2df51d205e8d3 /arch/arm | |
| parent | 73d5e06299195f4df82832cfc4a3a0c574c1e473 (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/arm')
| -rw-r--r-- | arch/arm/kernel/vdso.c | 9 |
1 files changed, 0 insertions, 9 deletions
diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c index fddd08a6e063..3408269d19c7 100644 --- a/arch/arm/kernel/vdso.c +++ b/arch/arm/kernel/vdso.c @@ -50,15 +50,6 @@ static const struct vm_special_mapping vdso_data_mapping = { static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) { - unsigned long new_size = new_vma->vm_end - new_vma->vm_start; - unsigned long vdso_size; - - /* without VVAR page */ - vdso_size = (vdso_total_pages - 1) << PAGE_SHIFT; - - if (vdso_size != new_size) - return -EINVAL; - current->mm->context.vdso = new_vma->vm_start; return 0; |