btrfs: convert btrfs_caching_control.count from atomic_t to refcount_t
authorElena Reshetova <elena.reshetova@intel.com>
Fri, 3 Mar 2017 08:55:14 +0000 (10:55 +0200)
committerDavid Sterba <dsterba@suse.com>
Tue, 18 Apr 2017 12:07:23 +0000 (14:07 +0200)
commit1e4f4714d59e3fdcde29ee12d40d2e96875a026f
tree1298d39f3b3dae00776bc15a1f6677b0bb32dfaf
parente76edab7f059bc1047c1865141e2709d70e74852
btrfs: convert btrfs_caching_control.count from atomic_t to refcount_t

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
fs/btrfs/ctree.h
fs/btrfs/extent-tree.c