4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Remi Pommarel <repk@xxxxxxxxxxxx> commit 421d467dc2d483175bad4fb76a31b9e5a3d744cf upstream. When batadv_v_ogm_aggr_send is called for an inactive interface, the skb is silently dropped by batadv_v_ogm_send_to_if() but never freed causing the following memory leak: unreferenced object 0xffff00000c164800 (size 512): comm "kworker/u8:1", pid 2648, jiffies 4295122303 (age 97.656s) hex dump (first 32 bytes): 00 80 af 09 00 00 ff ff e1 09 00 00 75 01 60 83 ............u.`. 1f 00 00 00 b8 00 00 00 15 00 05 00 da e3 d3 64 ...............d backtrace: [<0000000007ad20f6>] __kmalloc_track_caller+0x1a8/0x310 [<00000000d1029e55>] kmalloc_reserve.constprop.0+0x70/0x13c [<000000008b9d4183>] __alloc_skb+0xec/0x1fc [<00000000c7af5051>] __netdev_alloc_skb+0x48/0x23c [<00000000642ee5f5>] batadv_v_ogm_aggr_send+0x50/0x36c [<0000000088660bd7>] batadv_v_ogm_aggr_work+0x24/0x40 [<0000000042fc2606>] process_one_work+0x3b0/0x610 [<000000002f2a0b1c>] worker_thread+0xa0/0x690 [<0000000059fae5d4>] kthread+0x1fc/0x210 [<000000000c587d3a>] ret_from_fork+0x10/0x20 Free the skb in that case to fix this leak. Cc: stable@xxxxxxxxxxxxxxx Fixes: 0da0035942d4 ("batman-adv: OGMv2 - add basic infrastructure") Signed-off-by: Remi Pommarel <repk@xxxxxxxxxxxx> Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx> Signed-off-by: Simon Wunderlich <sw@xxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/batman-adv/bat_v_ogm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/batman-adv/bat_v_ogm.c +++ b/net/batman-adv/bat_v_ogm.c @@ -119,8 +119,10 @@ static void batadv_v_ogm_send_to_if(stru { struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); - if (hard_iface->if_status != BATADV_IF_ACTIVE) + if (hard_iface->if_status != BATADV_IF_ACTIVE) { + kfree_skb(skb); return; + } batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX); batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,