diff options
| author | Elena Reshetova <elena.reshetova@intel.com> | 2017-03-03 11:15:07 +0200 |
|---|---|---|
| committer | Ilya Dryomov <idryomov@gmail.com> | 2017-05-04 09:19:18 +0200 |
| commit | 805692d0e0f7dec42b5e05fb8b2a5c172f66a3c2 (patch) | |
| tree | c12a31d63fa29a8d5dba953d484b835b25a4b71a | |
| parent | 3997c01d260ed00d712b051fdab022a08719441e (diff) | |
| download | linux-805692d0e0f7dec42b5e05fb8b2a5c172f66a3c2.tar.bz2 | |
ceph: convert ceph_cap_snap.nref 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: Ilya Dryomov <idryomov@gmail.com>
| -rw-r--r-- | fs/ceph/caps.c | 4 | ||||
| -rw-r--r-- | fs/ceph/snap.c | 2 | ||||
| -rw-r--r-- | fs/ceph/super.h | 5 |
3 files changed, 6 insertions, 5 deletions
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 68c78be19d5b..60185434162a 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -1389,7 +1389,7 @@ static void __ceph_flush_snaps(struct ceph_inode_info *ci, first_tid = cf->tid + 1; capsnap = container_of(cf, struct ceph_cap_snap, cap_flush); - atomic_inc(&capsnap->nref); + refcount_inc(&capsnap->nref); spin_unlock(&ci->i_ceph_lock); dout("__flush_snaps %p capsnap %p tid %llu %s\n", @@ -2202,7 +2202,7 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, inode, capsnap, cf->tid, ceph_cap_string(capsnap->dirty)); - atomic_inc(&capsnap->nref); + refcount_inc(&capsnap->nref); spin_unlock(&ci->i_ceph_lock); ret = __send_flush_snap(inode, session, capsnap, cap->mseq, diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c index 8f8b41c2ef0f..dab5d6732345 100644 --- a/fs/ceph/snap.c +++ b/fs/ceph/snap.c @@ -519,7 +519,7 @@ void ceph_queue_cap_snap(struct ceph_inode_info *ci) capsnap->need_flush ? "" : "no_flush"); ihold(inode); - atomic_set(&capsnap->nref, 1); + refcount_set(&capsnap->nref, 1); INIT_LIST_HEAD(&capsnap->ci_item); capsnap->follows = old_snapc->seq; diff --git a/fs/ceph/super.h b/fs/ceph/super.h index fe6b9cfc4013..c68e6a045fb9 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -14,6 +14,7 @@ #include <linux/writeback.h> #include <linux/slab.h> #include <linux/posix_acl.h> +#include <linux/refcount.h> #include <linux/ceph/libceph.h> @@ -162,7 +163,7 @@ struct ceph_cap_flush { * data before flushing the snapped state (tracked here) back to the MDS. */ struct ceph_cap_snap { - atomic_t nref; + refcount_t nref; struct list_head ci_item; struct ceph_cap_flush cap_flush; @@ -191,7 +192,7 @@ struct ceph_cap_snap { static inline void ceph_put_cap_snap(struct ceph_cap_snap *capsnap) { - if (atomic_dec_and_test(&capsnap->nref)) { + if (refcount_dec_and_test(&capsnap->nref)) { if (capsnap->xattr_blob) ceph_buffer_put(capsnap->xattr_blob); kfree(capsnap); |