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| author |   Elena Reshetova <elena.reshetova@intel.com> | 2017-03-03 10:55:18 +0200 |
|---|---|---|
| committer |   David Sterba <dsterba@suse.com> | 2017-04-18 14:07:23 +0200 |
| commit | 0700cea7c8b387c8c6bc4de79b197baa0b3fc4a3 (patch) | |
| tree | 7bec132f997899bc7000ed108d539067438fd21f /fs/btrfs | |
| parent | btrfs: convert btrfs_delayed_item.refs from atomic_t to refcount_t (diff) | |
| download | linux-dev-0700cea7c8b387c8c6bc4de79b197baa0b3fc4a3.tar.xz linux-dev-0700cea7c8b387c8c6bc4de79b197baa0b3fc4a3.zip | |
btrfs: convert btrfs_root.refs 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>
Diffstat (limited to 'fs/btrfs')
| -rw-r--r-- | fs/btrfs/ctree.h | 2 | ||||
| -rw-r--r-- | fs/btrfs/disk-io.c | 2 | ||||
| -rw-r--r-- | fs/btrfs/disk-io.h | 4 |
3 files changed, 4 insertions, 4 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index cdfc2a46448b..285566cc2f7d 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1222,7 +1222,7 @@ struct btrfs_root { dev_t anon_dev; spinlock_t root_item_lock; - atomic_t refs; + refcount_t refs; struct mutex delalloc_mutex; spinlock_t delalloc_lock; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 3748bc54a6ab..bd415e1dd114 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1340,7 +1340,7 @@ static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info, atomic_set(&root->log_writers, 0); atomic_set(&root->log_batch, 0); atomic_set(&root->orphan_inodes, 0); - atomic_set(&root->refs, 1); + refcount_set(&root->refs, 1); atomic_set(&root->will_be_snapshoted, 0); atomic64_set(&root->qgroup_meta_rsv, 0); root->log_transid = 0; diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h index 2e0ec29bfd69..21f1ceb85b76 100644 --- a/fs/btrfs/disk-io.h +++ b/fs/btrfs/disk-io.h @@ -101,14 +101,14 @@ struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info); */ static inline struct btrfs_root *btrfs_grab_fs_root(struct btrfs_root *root) { - if (atomic_inc_not_zero(&root->refs)) + if (refcount_inc_not_zero(&root->refs)) return root; return NULL; } static inline void btrfs_put_fs_root(struct btrfs_root *root) { - if (atomic_dec_and_test(&root->refs)) + if (refcount_dec_and_test(&root->refs)) kfree(root); } |