From b7f0292094cbe31f82f2cd9623c8356cc7cf9566 Mon Sep 17 00:00:00 2001 From: "Reshetova, Elena" Date: Tue, 4 Jul 2017 15:53:16 +0300 Subject: [PATCH] net, rds: convert rds_incoming.i_refcount 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 Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller --- net/rds/rds.h | 3 ++- net/rds/recv.c | 12 ++++++------ 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/net/rds/rds.h b/net/rds/rds.h index 4a25db7075b1..35ceaa2139c3 100644 --- a/net/rds/rds.h +++ b/net/rds/rds.h @@ -8,6 +8,7 @@ #include #include #include +#include #include "info.h" @@ -261,7 +262,7 @@ struct rds_ext_header_rdma_dest { #define RDS_MSG_RX_CMSG 3 struct rds_incoming { - atomic_t i_refcount; + refcount_t i_refcount; struct list_head i_item; struct rds_connection *i_conn; struct rds_conn_path *i_conn_path; diff --git a/net/rds/recv.c b/net/rds/recv.c index 373a6aa1d976..b25bcfe411ca 100644 --- a/net/rds/recv.c +++ b/net/rds/recv.c @@ -45,7 +45,7 @@ void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn, { int i; - atomic_set(&inc->i_refcount, 1); + refcount_set(&inc->i_refcount, 1); INIT_LIST_HEAD(&inc->i_item); inc->i_conn = conn; inc->i_saddr = saddr; @@ -61,7 +61,7 @@ EXPORT_SYMBOL_GPL(rds_inc_init); void rds_inc_path_init(struct rds_incoming *inc, struct rds_conn_path *cp, __be32 saddr) { - atomic_set(&inc->i_refcount, 1); + refcount_set(&inc->i_refcount, 1); INIT_LIST_HEAD(&inc->i_item); inc->i_conn = cp->cp_conn; inc->i_conn_path = cp; @@ -74,14 +74,14 @@ EXPORT_SYMBOL_GPL(rds_inc_path_init); static void rds_inc_addref(struct rds_incoming *inc) { - rdsdebug("addref inc %p ref %d\n", inc, atomic_read(&inc->i_refcount)); - atomic_inc(&inc->i_refcount); + rdsdebug("addref inc %p ref %d\n", inc, refcount_read(&inc->i_refcount)); + refcount_inc(&inc->i_refcount); } void rds_inc_put(struct rds_incoming *inc) { - rdsdebug("put inc %p ref %d\n", inc, atomic_read(&inc->i_refcount)); - if (atomic_dec_and_test(&inc->i_refcount)) { + rdsdebug("put inc %p ref %d\n", inc, refcount_read(&inc->i_refcount)); + if (refcount_dec_and_test(&inc->i_refcount)) { BUG_ON(!list_empty(&inc->i_item)); inc->i_conn->c_trans->inc_free(inc); -- 2.20.1