[PATCH 30/36] net, sctp: convert sctp_datamsg.refcnt from atomic_t to refcount_t
From: Elena Reshetova <elena.reshetova@intel.com>
Date: 2017-07-04 12:58:15
Also in:
bridge, linux-hams, linux-nfs, linux-rdma, linux-sctp, lkml
Subsystem:
networking [general], sctp protocol, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Marcelo Ricardo Leitner, Xin Long, Linus Torvalds
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 <redacted> Signed-off-by: Kees Cook <redacted> Signed-off-by: David Windsor <redacted> --- include/net/sctp/structs.h | 2 +- net/sctp/chunk.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 07c11fe..4d7c855 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h@@ -496,7 +496,7 @@ struct sctp_datamsg { /* Chunks waiting to be submitted to lower layer. */ struct list_head chunks; /* Reference counting. */ - atomic_t refcnt; + refcount_t refcnt; /* When is this message no longer interesting to the peer? */ unsigned long expires_at; /* Did the messenge fail to send? */
diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
index 81466f6..1323d41 100644
--- a/net/sctp/chunk.c
+++ b/net/sctp/chunk.c@@ -49,7 +49,7 @@ /* Initialize datamsg from memory. */ static void sctp_datamsg_init(struct sctp_datamsg *msg) { - atomic_set(&msg->refcnt, 1); + refcount_set(&msg->refcnt, 1); msg->send_failed = 0; msg->send_error = 0; msg->can_delay = 1;
@@ -136,13 +136,13 @@ static void sctp_datamsg_destroy(struct sctp_datamsg *msg) /* Hold a reference. */ static void sctp_datamsg_hold(struct sctp_datamsg *msg) { - atomic_inc(&msg->refcnt); + refcount_inc(&msg->refcnt); } /* Release a reference. */ void sctp_datamsg_put(struct sctp_datamsg *msg) { - if (atomic_dec_and_test(&msg->refcnt)) + if (refcount_dec_and_test(&msg->refcnt)) sctp_datamsg_destroy(msg); }
--
2.7.4