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| author | Elena Reshetova <elena.reshetova@intel.com> | 2017-03-17 14:10:27 +0200 |
|---|---|---|
| committer | Ilya Dryomov <idryomov@gmail.com> | 2017-05-04 09:19:18 +0200 |
| commit | 06dfa96399a9a3280dd81e47f8696aa89f1783e7 (patch) | |
| tree | 1f5b529b617e1607087e096be6640b0208ec54aa | |
| parent | 805692d0e0f7dec42b5e05fb8b2a5c172f66a3c2 (diff) | |
| download | linux-stable-06dfa96399a9a3280dd81e47f8696aa89f1783e7.tar.gz linux-stable-06dfa96399a9a3280dd81e47f8696aa89f1783e7.tar.bz2 linux-stable-06dfa96399a9a3280dd81e47f8696aa89f1783e7.zip | |
libceph: convert ceph_snap_context.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-- | include/linux/ceph/libceph.h | 3 | ||||
| -rw-r--r-- | net/ceph/snapshot.c | 6 |
2 files changed, 5 insertions, 4 deletions
diff --git a/include/linux/ceph/libceph.h b/include/linux/ceph/libceph.h index cecbf5a26e5a..3229ae6c7846 100644 --- a/include/linux/ceph/libceph.h +++ b/include/linux/ceph/libceph.h @@ -14,6 +14,7 @@ #include <linux/wait.h> #include <linux/writeback.h> #include <linux/slab.h> +#include <linux/refcount.h> #include <linux/ceph/types.h> #include <linux/ceph/messenger.h> @@ -161,7 +162,7 @@ struct ceph_client { * dirtied. */ struct ceph_snap_context { - atomic_t nref; + refcount_t nref; u64 seq; u32 num_snaps; u64 snaps[]; diff --git a/net/ceph/snapshot.c b/net/ceph/snapshot.c index 705414e78ae0..e14a5d038656 100644 --- a/net/ceph/snapshot.c +++ b/net/ceph/snapshot.c @@ -49,7 +49,7 @@ struct ceph_snap_context *ceph_create_snap_context(u32 snap_count, if (!snapc) return NULL; - atomic_set(&snapc->nref, 1); + refcount_set(&snapc->nref, 1); snapc->num_snaps = snap_count; return snapc; @@ -59,7 +59,7 @@ EXPORT_SYMBOL(ceph_create_snap_context); struct ceph_snap_context *ceph_get_snap_context(struct ceph_snap_context *sc) { if (sc) - atomic_inc(&sc->nref); + refcount_inc(&sc->nref); return sc; } EXPORT_SYMBOL(ceph_get_snap_context); @@ -68,7 +68,7 @@ void ceph_put_snap_context(struct ceph_snap_context *sc) { if (!sc) return; - if (atomic_dec_and_test(&sc->nref)) { + if (refcount_dec_and_test(&sc->nref)) { /*printk(" deleting snap_context %p\n", sc);*/ kfree(sc); } |