From d25189ca8665e3ed493c7bc0607e62c2fcb314ad Mon Sep 17 00:00:00 2001 From: "Reshetova, Elena" Date: Tue, 4 Jul 2017 15:53:09 +0300 Subject: [PATCH] net, ipx: convert ipx_interface.refcnt 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/ipx.h | 7 ++++--- net/ipx/af_ipx.c | 6 +++--- net/ipx/ipx_proc.c | 2 +- 3 files changed, 8 insertions(+), 7 deletions(-) diff --git a/include/net/ipx.h b/include/net/ipx.h index e5cff6811b30..2de12814ab81 100644 --- a/include/net/ipx.h +++ b/include/net/ipx.h @@ -14,6 +14,7 @@ #include #include #include +#include struct ipx_address { __be32 net; @@ -54,7 +55,7 @@ struct ipx_interface { /* IPX address */ __be32 if_netnum; unsigned char if_node[IPX_NODE_LEN]; - atomic_t refcnt; + refcount_t refcnt; /* physical device info */ struct net_device *if_dev; @@ -139,7 +140,7 @@ const char *ipx_device_name(struct ipx_interface *intrfc); static __inline__ void ipxitf_hold(struct ipx_interface *intrfc) { - atomic_inc(&intrfc->refcnt); + refcount_inc(&intrfc->refcnt); } void ipxitf_down(struct ipx_interface *intrfc); @@ -157,7 +158,7 @@ int ipxrtr_ioctl(unsigned int cmd, void __user *arg); static __inline__ void ipxitf_put(struct ipx_interface *intrfc) { - if (atomic_dec_and_test(&intrfc->refcnt)) + if (refcount_dec_and_test(&intrfc->refcnt)) ipxitf_down(intrfc); } diff --git a/net/ipx/af_ipx.c b/net/ipx/af_ipx.c index fa31ef29e3fa..ac598ec90589 100644 --- a/net/ipx/af_ipx.c +++ b/net/ipx/af_ipx.c @@ -308,7 +308,7 @@ void ipxitf_down(struct ipx_interface *intrfc) static void __ipxitf_put(struct ipx_interface *intrfc) { - if (atomic_dec_and_test(&intrfc->refcnt)) + if (refcount_dec_and_test(&intrfc->refcnt)) __ipxitf_down(intrfc); } @@ -876,7 +876,7 @@ static struct ipx_interface *ipxitf_alloc(struct net_device *dev, __be32 netnum, intrfc->if_ipx_offset = ipx_offset; intrfc->if_sknum = IPX_MIN_EPHEMERAL_SOCKET; INIT_HLIST_HEAD(&intrfc->if_sklist); - atomic_set(&intrfc->refcnt, 1); + refcount_set(&intrfc->refcnt, 1); spin_lock_init(&intrfc->if_sklist_lock); } @@ -1105,7 +1105,7 @@ static struct ipx_interface *ipxitf_auto_create(struct net_device *dev, memcpy((char *)&(intrfc->if_node[IPX_NODE_LEN-dev->addr_len]), dev->dev_addr, dev->addr_len); spin_lock_init(&intrfc->if_sklist_lock); - atomic_set(&intrfc->refcnt, 1); + refcount_set(&intrfc->refcnt, 1); ipxitf_insert(intrfc); dev_hold(dev); } diff --git a/net/ipx/ipx_proc.c b/net/ipx/ipx_proc.c index c1d247ebe916..7d75e4c5c75d 100644 --- a/net/ipx/ipx_proc.c +++ b/net/ipx/ipx_proc.c @@ -53,7 +53,7 @@ static int ipx_seq_interface_show(struct seq_file *seq, void *v) seq_printf(seq, "%-11s", ipx_device_name(i)); seq_printf(seq, "%-9s", ipx_frame_name(i->if_dlink_type)); #ifdef IPX_REFCNT_DEBUG - seq_printf(seq, "%6d", atomic_read(&i->refcnt)); + seq_printf(seq, "%6d", refcount_read(&i->refcnt)); #endif seq_puts(seq, "\n"); out: