This is a note to let you know that I've just added the patch titled net: caif: add proper error handling to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-caif-add-proper-error-handling.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From a2805dca5107d5603f4bbc027e81e20d93476e96 Mon Sep 17 00:00:00 2001 From: Pavel Skripkin <paskripkin@xxxxxxxxx> Date: Thu, 3 Jun 2021 19:38:51 +0300 Subject: net: caif: add proper error handling From: Pavel Skripkin <paskripkin@xxxxxxxxx> 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@xxxxxxxxxxxxxxx Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/net/caif/caif_dev.h | 2 +- include/net/caif/cfcnfg.h | 2 +- net/caif/caif_dev.c | 8 +++++--- net/caif/cfcnfg.c | 16 +++++++++++----- 4 files changed, 18 insertions(+), 10 deletions(-) --- a/include/net/caif/caif_dev.h +++ b/include/net/caif/caif_dev.h @@ -119,7 +119,7 @@ void caif_free_client(struct cflayer *ad * 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 *, --- 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, --- a/net/caif/caif_dev.c +++ b/net/caif/caif_dev.c @@ -303,7 +303,7 @@ static void dev_flowctrl(struct net_devi 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 *, @@ -314,11 +314,12 @@ void caif_enroll_dev(struct net_device * 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); @@ -340,7 +341,7 @@ void caif_enroll_dev(struct net_device * sizeof(caifd->layer.name) - 1); caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0; caifd->layer.transmit = transmit; - cfcnfg_add_phy_layer(cfg, + res = cfcnfg_add_phy_layer(cfg, dev, &caifd->layer, pref, @@ -350,6 +351,7 @@ void caif_enroll_dev(struct net_device * mutex_unlock(&caifdevs->lock); if (rcv_func) *rcv_func = receive; + return res; } EXPORT_SYMBOL(caif_enroll_dev); --- a/net/caif/cfcnfg.c +++ b/net/caif/cfcnfg.c @@ -455,7 +455,7 @@ 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, @@ -464,7 +464,7 @@ 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); @@ -478,12 +478,15 @@ 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; @@ -497,8 +500,10 @@ 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); @@ -516,11 +521,12 @@ 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); Patches currently in stable-queue which might be from paskripkin@xxxxxxxxx are queue-4.4/net-caif-fix-memory-leak-in-cfusbl_device_notify.patch queue-4.4/net-caif-added-cfserl_release-function.patch queue-4.4/net-caif-add-proper-error-handling.patch queue-4.4/net-caif-fix-memory-leak-in-caif_device_notify.patch