From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- include/net/net_failover.h | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 include/net/net_failover.h (limited to 'include/net/net_failover.h') diff --git a/include/net/net_failover.h b/include/net/net_failover.h new file mode 100644 index 000000000..b12a1c469 --- /dev/null +++ b/include/net/net_failover.h @@ -0,0 +1,40 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (c) 2018, Intel Corporation. */ + +#ifndef _NET_FAILOVER_H +#define _NET_FAILOVER_H + +#include + +/* failover state */ +struct net_failover_info { + /* primary netdev with same MAC */ + struct net_device __rcu *primary_dev; + + /* standby netdev */ + struct net_device __rcu *standby_dev; + + /* primary netdev stats */ + struct rtnl_link_stats64 primary_stats; + + /* standby netdev stats */ + struct rtnl_link_stats64 standby_stats; + + /* aggregated stats */ + struct rtnl_link_stats64 failover_stats; + + /* spinlock while updating stats */ + spinlock_t stats_lock; +}; + +struct failover *net_failover_create(struct net_device *standby_dev); +void net_failover_destroy(struct failover *failover); + +#define FAILOVER_VLAN_FEATURES (NETIF_F_HW_CSUM | NETIF_F_SG | \ + NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \ + NETIF_F_HIGHDMA | NETIF_F_LRO) + +#define FAILOVER_ENC_FEATURES (NETIF_F_HW_CSUM | NETIF_F_SG | \ + NETIF_F_RXCSUM | NETIF_F_ALL_TSO) + +#endif /* _NET_FAILOVER_H */ -- cgit v1.3.1