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 <[email protected]> Signed-off-by: Hans Liljestrand <[email protected]> Signed-off-by: Kees Cook <[email protected]> Signed-off-by: David Windsor <[email protected]> --- fs/ncpfs/sock.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/ncpfs/sock.c b/fs/ncpfs/sock.c index 4bfeae2..c9d5012 100644 --- a/fs/ncpfs/sock.c +++ b/fs/ncpfs/sock.c @@ -28,6 +28,7 @@ #include <linux/ipx.h> #include <linux/poll.h> #include <linux/file.h> +#include <linux/refcount.h> #include "ncp_fs.h" @@ -51,7 +52,7 @@ static int _send(struct socket *sock, const void *buff, int len) struct ncp_request_reply { struct list_head req; wait_queue_head_t wq; - atomic_t refs; + refcount_t refs; unsigned char* reply_buf; size_t datalen; int result; @@ -71,7 +72,7 @@ static inline struct ncp_request_reply* ncp_alloc_req(void) return NULL; init_waitqueue_head(&req->wq); - atomic_set(&req->refs, (1)); + refcount_set(&req->refs, (1)); req->status = RQ_IDLE; return req; @@ -79,12 +80,12 @@ static inline struct ncp_request_reply* ncp_alloc_req(void) static void ncp_req_get(struct ncp_request_reply *req) { - atomic_inc(&req->refs); + refcount_inc(&req->refs); } static void ncp_req_put(struct ncp_request_reply *req) { - if (atomic_dec_and_test(&req->refs)) + if (refcount_dec_and_test(&req->refs)) kfree(req); } -- 2.7.4
