dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()grafted

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 <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 88 insertions, 0 deletions

diff --git a/drivers/net/Makefile b/drivers/net/Makefile
new file mode 100644
index 000000000..88e4c485d
--- /dev/null
+++ b/drivers/net/Makefile
@@ -0,0 +1,88 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the Linux network device drivers.
+#
+
+#
+# Networking Core Drivers
+#
+obj-$(CONFIG_BONDING) += bonding/
+obj-$(CONFIG_IPVLAN) += ipvlan/
+obj-$(CONFIG_IPVTAP) += ipvlan/
+obj-$(CONFIG_DUMMY) += dummy.o
+obj-$(CONFIG_WIREGUARD) += wireguard/
+obj-$(CONFIG_OVPN) += ovpn/
+obj-$(CONFIG_EQUALIZER) += eql.o
+obj-$(CONFIG_IFB) += ifb.o
+obj-$(CONFIG_MACSEC) += macsec.o
+obj-$(CONFIG_AMT) += amt.o
+obj-$(CONFIG_MACVLAN) += macvlan.o
+obj-$(CONFIG_MACVTAP) += macvtap.o
+obj-$(CONFIG_MII) += mii.o
+obj-$(CONFIG_MDIO) += mdio.o
+obj-$(CONFIG_NET) += loopback.o
+obj-$(CONFIG_NETCONSOLE) += netconsole.o
+obj-$(CONFIG_NETKIT) += netkit.o
+obj-y += phy/
+obj-y += pse-pd/
+obj-y += mdio/
+obj-y += pcs/
+obj-$(CONFIG_RIONET) += rionet.o
+obj-$(CONFIG_NET_TEAM) += team/
+obj-$(CONFIG_TUN) += tun.o
+obj-$(CONFIG_TAP) += tap.o
+obj-$(CONFIG_VETH) += veth.o
+obj-$(CONFIG_VIRTIO_NET) += virtio_net.o
+obj-$(CONFIG_VXLAN) += vxlan/
+obj-$(CONFIG_GENEVE) += geneve.o
+obj-$(CONFIG_BAREUDP) += bareudp.o
+obj-$(CONFIG_GTP) += gtp.o
+obj-$(CONFIG_NLMON) += nlmon.o
+obj-$(CONFIG_PFCP) += pfcp.o
+obj-$(CONFIG_NET_VRF) += vrf.o
+obj-$(CONFIG_VSOCKMON) += vsockmon.o
+obj-$(CONFIG_MHI_NET) += mhi_net.o
+
+#
+# Networking Drivers
+#
+obj-$(CONFIG_ARCNET) += arcnet/
+obj-$(CONFIG_CAN) += can/
+ifdef CONFIG_NET_DSA
+obj-y += dsa/
+endif
+obj-$(CONFIG_ETHERNET) += ethernet/
+obj-$(CONFIG_FDDI) += fddi/
+obj-$(CONFIG_QCOM_IPA) += ipa/
+obj-$(CONFIG_PLIP) += plip/
+obj-$(CONFIG_PPP) += ppp/
+obj-$(CONFIG_PPP_ASYNC) += ppp/
+obj-$(CONFIG_PPP_BSDCOMP) += ppp/
+obj-$(CONFIG_PPP_DEFLATE) += ppp/
+obj-$(CONFIG_PPP_MPPE) += ppp/
+obj-$(CONFIG_PPP_SYNC_TTY) += ppp/
+obj-$(CONFIG_PPPOE) += ppp/
+obj-$(CONFIG_PPPOL2TP) += ppp/
+obj-$(CONFIG_PPTP) += ppp/
+obj-$(CONFIG_SLIP) += slip/
+obj-$(CONFIG_SLHC) += slip/
+obj-$(CONFIG_SUNGEM_PHY) += sungem_phy.o
+obj-$(CONFIG_WAN) += wan/
+obj-$(CONFIG_WLAN) += wireless/
+obj-$(CONFIG_IEEE802154) += ieee802154/
+obj-$(CONFIG_WWAN) += wwan/
+obj-$(CONFIG_MCTP) += mctp/
+
+obj-$(CONFIG_VMXNET3) += vmxnet3/
+obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
+obj-$(CONFIG_XEN_NETDEV_BACKEND) += xen-netback/
+
+obj-$(CONFIG_USB_NET_DRIVERS) += usb/
+
+obj-$(CONFIG_HYPERV_NET) += hyperv/
+obj-$(CONFIG_NTB_NETDEV) += ntb_netdev.o
+
+obj-$(CONFIG_FUJITSU_ES) += fjes/
+obj-$(CONFIG_USB4_NET) += thunderbolt/
+obj-$(CONFIG_NETDEVSIM) += netdevsim/
+obj-$(CONFIG_NET_FAILOVER) += net_failover.o