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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2015-07-06 23:18:37 +0300 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2015-08-12 16:33:20 +0200 |
| commit | e2506476534cff7bb3697fbe0654fdefd101bc80 (patch) | |
| tree | 45ef9383f81ba816d96b40c24ace0315185b8bf7 /net | |
| parent | 350ae75ae2224db9b484a4a64914d8af6a582c92 (diff) | |
| download | kernel_samsung_smdk4412-e2506476534cff7bb3697fbe0654fdefd101bc80.zip kernel_samsung_smdk4412-e2506476534cff7bb3697fbe0654fdefd101bc80.tar.gz kernel_samsung_smdk4412-e2506476534cff7bb3697fbe0654fdefd101bc80.tar.bz2 | |
mm: avoid setting up anonymous pages into file mapping
commit 6b7339f4c31ad69c8e9c0b2859276e22cf72176d upstream.
Reading page fault handler code I've noticed that under right
circumstances kernel would map anonymous pages into file mappings: if
the VMA doesn't have vm_ops->fault() and the VMA wasn't fully populated
on ->mmap(), kernel would handle page fault to not populated pte with
do_anonymous_page().
Let's change page fault handler to use do_anonymous_page() only on
anonymous VMA (->vm_ops == NULL) and make sure that the VMA is not
shared.
For file mappings without vm_ops->fault() or shred VMA without vm_ops,
page fault on pte_none() entry would lead to SIGBUS.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net')
0 files changed, 0 insertions, 0 deletions