diff options
author | Andrea Arcangeli <aarcange@redhat.com> | 2016-02-05 15:36:13 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-02-05 18:10:40 -0800 |
commit | acf128d048c76aeaa99646bce3488d73be215f70 (patch) | |
tree | 73218b1077b2b1b8fed94fe8aca94326a6843b4f /lib | |
parent | af1ddcb5c63cfb9744c29e88db0bab6bb25ad76b (diff) |
mm: validate_mm browse_rb SMP race condition
The mmap_sem for reading in validate_mm called from expand_stack is not
enough to prevent the argumented rbtree rb_subtree_gap information to
change from under us because expand_stack may be running from other
threads concurrently which will hold the mmap_sem for reading too.
The argumented rbtree is updated with vma_gap_update under the
page_table_lock so use it in browse_rb() too to avoid false positives.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
0 files changed, 0 insertions, 0 deletions