[PATCH 06/18] net, decnet: convert dn_fib_info.fib_clntref from atomic_t to refcount_t
From: Elena Reshetova <elena.reshetova@intel.com>
Date: 2017-03-17 11:14:23
Also in:
bridge, linux-bluetooth, linux-hams, lkml
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, 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/dn_fib.h | 5 +++-- net/decnet/dn_fib.c | 6 +++--- 2 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/include/net/dn_fib.h b/include/net/dn_fib.h
index f2ca135..81210a8 100644
--- a/include/net/dn_fib.h
+++ b/include/net/dn_fib.h@@ -2,6 +2,7 @@ #define _NET_DN_FIB_H #include <linux/netlink.h> +#include <linux/refcount.h> extern const struct nla_policy rtm_dn_policy[];
@@ -28,7 +29,7 @@ struct dn_fib_info { struct dn_fib_info *fib_next; struct dn_fib_info *fib_prev; int fib_treeref; - atomic_t fib_clntref; + refcount_t fib_clntref; int fib_dead; unsigned int fib_flags; int fib_protocol;
@@ -130,7 +131,7 @@ void dn_fib_free_info(struct dn_fib_info *fi); static inline void dn_fib_info_put(struct dn_fib_info *fi) { - if (atomic_dec_and_test(&fi->fib_clntref)) + if (refcount_dec_and_test(&fi->fib_clntref)) dn_fib_free_info(fi); }
diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c
index 7af0ba61..85058c3 100644
--- a/net/decnet/dn_fib.c
+++ b/net/decnet/dn_fib.c@@ -389,7 +389,7 @@ struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct nlattr *att } fi->fib_treeref++; - atomic_inc(&fi->fib_clntref); + refcount_set(&fi->fib_clntref, 1); spin_lock(&dn_fib_info_lock); fi->fib_next = dn_fib_info_list; fi->fib_prev = NULL;
@@ -425,7 +425,7 @@ int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn switch (type) { case RTN_NAT: DN_FIB_RES_RESET(*res); - atomic_inc(&fi->fib_clntref); + refcount_inc(&fi->fib_clntref); return 0; case RTN_UNICAST: case RTN_LOCAL:
@@ -438,7 +438,7 @@ int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn } if (nhsel < fi->fib_nhs) { res->nh_sel = nhsel; - atomic_inc(&fi->fib_clntref); + refcount_inc(&fi->fib_clntref); return 0; } endfor_nexthops(fi);
--
2.7.4