fuse: convert fuse_conn.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: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
parent
ec99f6d31f
commit
095fc40ace
|
@ -449,7 +449,7 @@ struct fuse_conn {
|
|||
spinlock_t lock;
|
||||
|
||||
/** Refcount */
|
||||
atomic_t count;
|
||||
refcount_t count;
|
||||
|
||||
/** Number of fuse_dev's */
|
||||
atomic_t dev_count;
|
||||
|
|
|
@ -608,7 +608,7 @@ void fuse_conn_init(struct fuse_conn *fc)
|
|||
memset(fc, 0, sizeof(*fc));
|
||||
spin_lock_init(&fc->lock);
|
||||
init_rwsem(&fc->killsb);
|
||||
atomic_set(&fc->count, 1);
|
||||
refcount_set(&fc->count, 1);
|
||||
atomic_set(&fc->dev_count, 1);
|
||||
init_waitqueue_head(&fc->blocked_waitq);
|
||||
init_waitqueue_head(&fc->reserved_req_waitq);
|
||||
|
@ -631,7 +631,7 @@ EXPORT_SYMBOL_GPL(fuse_conn_init);
|
|||
|
||||
void fuse_conn_put(struct fuse_conn *fc)
|
||||
{
|
||||
if (atomic_dec_and_test(&fc->count)) {
|
||||
if (refcount_dec_and_test(&fc->count)) {
|
||||
if (fc->destroy_req)
|
||||
fuse_request_free(fc->destroy_req);
|
||||
fc->release(fc);
|
||||
|
@ -641,7 +641,7 @@ EXPORT_SYMBOL_GPL(fuse_conn_put);
|
|||
|
||||
struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
|
||||
{
|
||||
atomic_inc(&fc->count);
|
||||
refcount_inc(&fc->count);
|
||||
return fc;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(fuse_conn_get);
|
||||
|
|
Loading…
Reference in New Issue