From af4207494d9c8e089df80e9c1ceac44f2b3e7b53 Mon Sep 17 00:00:00 2001 From: "Reshetova, Elena" Date: Tue, 4 Jul 2017 15:53:11 +0300 Subject: [PATCH] net, netrom: convert nr_neigh.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 --- include/net/netrom.h | 7 ++++--- net/netrom/nr_route.c | 4 ++-- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/include/net/netrom.h b/include/net/netrom.h index 110350aca3df..cecb4fde0243 100644 --- a/include/net/netrom.h +++ b/include/net/netrom.h @@ -11,6 +11,7 @@ #include #include #include +#include #define NR_NETWORK_LEN 15 #define NR_TRANSPORT_LEN 5 @@ -93,7 +94,7 @@ struct nr_neigh { unsigned short count; unsigned int number; unsigned char failed; - atomic_t refcount; + refcount_t refcount; }; struct nr_route { @@ -128,11 +129,11 @@ static __inline__ void nr_node_put(struct nr_node *nr_node) } #define nr_neigh_hold(__nr_neigh) \ - atomic_inc(&((__nr_neigh)->refcount)) + refcount_inc(&((__nr_neigh)->refcount)) static __inline__ void nr_neigh_put(struct nr_neigh *nr_neigh) { - if (atomic_dec_and_test(&nr_neigh->refcount)) { + if (refcount_dec_and_test(&nr_neigh->refcount)) { if (nr_neigh->ax25) ax25_cb_put(nr_neigh->ax25); kfree(nr_neigh->digipeat); diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c index d72a4f1558f2..6b72970a0d6a 100644 --- a/net/netrom/nr_route.c +++ b/net/netrom/nr_route.c @@ -149,7 +149,7 @@ static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic, nr_neigh->count = 0; nr_neigh->number = nr_neigh_no++; nr_neigh->failed = 0; - atomic_set(&nr_neigh->refcount, 1); + refcount_set(&nr_neigh->refcount, 1); if (ax25_digi != NULL && ax25_digi->ndigi > 0) { nr_neigh->digipeat = kmemdup(ax25_digi, @@ -431,7 +431,7 @@ static int __must_check nr_add_neigh(ax25_address *callsign, nr_neigh->count = 0; nr_neigh->number = nr_neigh_no++; nr_neigh->failed = 0; - atomic_set(&nr_neigh->refcount, 1); + refcount_set(&nr_neigh->refcount, 1); if (ax25_digi != NULL && ax25_digi->ndigi > 0) { nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),