net: caif: add proper error handling

commit a2805dca5107d5603f4bbc027e81e20d93476e96 upstream.

caif_enroll_dev() can fail in some cases. Ingnoring
these cases can lead to memory leak due to not assigning
link_support pointer to anywhere.

Fixes: 7c18d2205ea7 ("caif: Restructure how link caif link layer enroll")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/net/caif/caif_dev.h b/include/net/caif/caif_dev.h
index 48ecca8..b655d86 100644 (file)
--- a/include/net/caif/caif_dev.h
+++ b/include/net/caif/caif_dev.h
@@ -119,7 +119,7 @@ void caif_free_client(struct cflayer *adap_layer);
  * The link_support layer is used to add any Link Layer specific
  * framing.
  */
-void caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
+int caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
                        struct cflayer *link_support, int head_room,
                        struct cflayer **layer, int (**rcv_func)(
                                struct sk_buff *, struct net_device *,

diff --git a/include/net/caif/cfcnfg.h b/include/net/caif/cfcnfg.h
index 2aa5e91..8819ff4 100644 (file)
--- a/include/net/caif/cfcnfg.h
+++ b/include/net/caif/cfcnfg.h
@@ -62,7 +62,7 @@ void cfcnfg_remove(struct cfcnfg *cfg);
  * @fcs:       Specify if checksum is used in CAIF Framing Layer.
  * @head_room: Head space needed by link specific protocol.
  */
-void
+int
 cfcnfg_add_phy_layer(struct cfcnfg *cnfg,
                     struct net_device *dev, struct cflayer *phy_layer,
                     enum cfcnfg_phy_preference pref,

diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index c10e5a5..fffbe41 100644 (file)
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -308,7 +308,7 @@ static void dev_flowctrl(struct net_device *dev, int on)
        caifd_put(caifd);
 }
 
-void caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
+int caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
                     struct cflayer *link_support, int head_room,
                     struct cflayer **layer,
                     int (**rcv_func)(struct sk_buff *, struct net_device *,
@@ -319,11 +319,12 @@ void caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
        enum cfcnfg_phy_preference pref;
        struct cfcnfg *cfg = get_cfcnfg(dev_net(dev));
        struct caif_device_entry_list *caifdevs;
+       int res;
 
        caifdevs = caif_device_list(dev_net(dev));
        caifd = caif_device_alloc(dev);
        if (!caifd)
-               return;
+               return -ENOMEM;
        *layer = &caifd->layer;
        spin_lock_init(&caifd->flow_lock);
 
@@ -344,7 +345,7 @@ void caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
        strlcpy(caifd->layer.name, dev->name,
                sizeof(caifd->layer.name));
        caifd->layer.transmit = transmit;
-       cfcnfg_add_phy_layer(cfg,
+       res = cfcnfg_add_phy_layer(cfg,
                                dev,
                                &caifd->layer,
                                pref,
@@ -354,6 +355,7 @@ void caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
        mutex_unlock(&caifdevs->lock);
        if (rcv_func)
                *rcv_func = receive;
+       return res;
 }
 EXPORT_SYMBOL(caif_enroll_dev);
 

diff --git a/net/caif/cfcnfg.c b/net/caif/cfcnfg.c
index 399239a..cac30e6 100644 (file)
--- a/net/caif/cfcnfg.c
+++ b/net/caif/cfcnfg.c
@@ -450,7 +450,7 @@ unlock:
        rcu_read_unlock();
 }
 
-void
+int
 cfcnfg_add_phy_layer(struct cfcnfg *cnfg,
                     struct net_device *dev, struct cflayer *phy_layer,
                     enum cfcnfg_phy_preference pref,
@@ -459,7 +459,7 @@ cfcnfg_add_phy_layer(struct cfcnfg *cnfg,
 {
        struct cflayer *frml;
        struct cfcnfg_phyinfo *phyinfo = NULL;
-       int i;
+       int i, res = 0;
        u8 phyid;
 
        mutex_lock(&cnfg->lock);
@@ -473,12 +473,15 @@ cfcnfg_add_phy_layer(struct cfcnfg *cnfg,
                        goto got_phyid;
        }
        pr_warn("Too many CAIF Link Layers (max 6)\n");
+       res = -EEXIST;
        goto out;
 
 got_phyid:
        phyinfo = kzalloc(sizeof(struct cfcnfg_phyinfo), GFP_ATOMIC);
-       if (!phyinfo)
+       if (!phyinfo) {
+               res = -ENOMEM;
                goto out_err;
+       }
 
        phy_layer->id = phyid;
        phyinfo->pref = pref;
@@ -492,8 +495,10 @@ got_phyid:
 
        frml = cffrml_create(phyid, fcs);
 
-       if (!frml)
+       if (!frml) {
+               res = -ENOMEM;
                goto out_err;
+       }
        phyinfo->frm_layer = frml;
        layer_set_up(frml, cnfg->mux);
 
@@ -511,11 +516,12 @@ got_phyid:
        list_add_rcu(&phyinfo->node, &cnfg->phys);
 out:
        mutex_unlock(&cnfg->lock);
-       return;
+       return res;
 
 out_err:
        kfree(phyinfo);
        mutex_unlock(&cnfg->lock);
+       return res;
 }
 EXPORT_SYMBOL(cfcnfg_add_phy_layer);