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, 41 insertions, 0 deletions

diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
new file mode 100644
index 000000000..3ee883c87
--- /dev/null
+++ b/drivers/memory/Makefile
@@ -0,0 +1,41 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for memory devices
+#
+
+obj-$(CONFIG_DDR)		+= jedec_ddr_data.o
+ifeq ($(CONFIG_DDR),y)
+obj-$(CONFIG_OF)		+= of_memory.o
+endif
+obj-$(CONFIG_ARM_PL172_MPMC)	+= pl172.o
+obj-$(CONFIG_ATMEL_EBI)		+= atmel-ebi.o
+obj-$(CONFIG_BRCMSTB_DPFE)	+= brcmstb_dpfe.o
+obj-$(CONFIG_BRCMSTB_MEMC)	+= brcmstb_memc.o
+obj-$(CONFIG_TI_AEMIF)		+= ti-aemif.o
+obj-$(CONFIG_TI_EMIF)		+= emif.o
+obj-$(CONFIG_OMAP_GPMC)		+= omap-gpmc.o
+obj-$(CONFIG_FSL_CORENET_CF)	+= fsl-corenet-cf.o
+obj-$(CONFIG_FSL_IFC)		+= fsl_ifc.o
+obj-$(CONFIG_MVEBU_DEVBUS)	+= mvebu-devbus.o
+obj-$(CONFIG_JZ4780_NEMC)	+= jz4780-nemc.o
+obj-$(CONFIG_MTK_SMI)		+= mtk-smi.o
+obj-$(CONFIG_DA8XX_DDRCTL)	+= da8xx-ddrctl.o
+obj-$(CONFIG_PL353_SMC)		+= pl353-smc.o
+obj-$(CONFIG_RENESAS_RPCIF)	+= renesas-rpc-if.o
+obj-$(CONFIG_STM32_FMC2_EBI)	+= stm32-fmc2-ebi.o
+obj-$(CONFIG_STM32_OMM)		+= stm32_omm.o
+
+obj-$(CONFIG_SAMSUNG_MC)	+= samsung/
+obj-$(CONFIG_TEGRA_MC)		+= tegra/
+obj-$(CONFIG_TI_EMIF_SRAM)	+= ti-emif-sram.o
+obj-$(CONFIG_FPGA_DFL_EMIF)	+= dfl-emif.o
+
+ti-emif-sram-objs		:= ti-emif-pm.o ti-emif-sram-pm.o
+
+$(obj)/ti-emif-sram-pm.o: $(obj)/ti-emif-asm-offsets.h
+
+$(obj)/ti-emif-asm-offsets.h: $(obj)/emif-asm-offsets.s FORCE
+	$(call filechk,offsets,__TI_EMIF_ASM_OFFSETS_H__)
+
+targets += emif-asm-offsets.s
+clean-files += ti-emif-asm-offsets.h