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 --- scripts/Makefile.clean | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 scripts/Makefile.clean (limited to 'scripts/Makefile.clean') diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean new file mode 100644 index 000000000..6ead00ec7 --- /dev/null +++ b/scripts/Makefile.clean @@ -0,0 +1,63 @@ +# SPDX-License-Identifier: GPL-2.0 +# ========================================================================== +# Cleaning up +# ========================================================================== + +src := $(srcroot)/$(obj) + +PHONY := __clean +__clean: + +include $(srctree)/scripts/Kbuild.include +include $(kbuild-file) + +# Figure out what we need to build from the various variables +# ========================================================================== + +subdir-ymn := $(sort $(subdir-y) $(subdir-m) $(subdir-) \ + $(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m) $(obj-)))) + +# Add subdir path + +subdir-ymn := $(addprefix $(obj)/,$(subdir-ymn)) + +# build a list of files to remove, usually relative to the current +# directory + +__clean-files := \ + $(clean-files) $(targets) $(hostprogs) $(userprogs) \ + $(extra-y) $(extra-m) $(extra-) \ + $(always-y) $(always-m) $(always-) \ + $(hostprogs-always-y) $(hostprogs-always-m) $(hostprogs-always-) \ + $(userprogs-always-y) $(userprogs-always-m) $(userprogs-always-) + +__clean-files := $(filter-out $(no-clean-files), $(__clean-files)) + +__clean-files := $(wildcard $(addprefix $(obj)/, $(__clean-files))) + +# ========================================================================== + +# To make this rule robust against "Argument list too long" error, +# remove $(obj)/ prefix, and restore it by a shell command. +quiet_cmd_clean = CLEAN $(obj) + cmd_clean = printf '$(obj)/%s ' $(patsubst $(obj)/%,%,$(__clean-files)) | xargs rm -rf + +__clean: $(subdir-ymn) +ifneq ($(strip $(__clean-files)),) + $(call cmd,clean) +endif + @: + + +# =========================================================================== +# Generic stuff +# =========================================================================== + +# Descending +# --------------------------------------------------------------------------- + +PHONY += $(subdir-ymn) +$(subdir-ymn): + $(Q)$(MAKE) $(clean)=$@ + +.PHONY: $(PHONY) -- cgit v1.3.1