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.vdsoinst | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 scripts/Makefile.vdsoinst (limited to 'scripts/Makefile.vdsoinst') diff --git a/scripts/Makefile.vdsoinst b/scripts/Makefile.vdsoinst new file mode 100644 index 000000000..d9f724321 --- /dev/null +++ b/scripts/Makefile.vdsoinst @@ -0,0 +1,45 @@ +# SPDX-License-Identifier: GPL-2.0-only +# ========================================================================== +# Install unstripped copies of vDSO +# ========================================================================== + +PHONY := __default +__default: + @: + +include $(srctree)/scripts/Kbuild.include + +install-dir := $(MODLIB)/vdso + +define gen_install_rules + +dest := $(install-dir)/$$(patsubst %.dbg,%,$$(notdir $(1))) + +__default: $$(dest) +$$(dest): $(1) FORCE + $$(call cmd,install) + +build-id-file := $$(shell $(READELF) -n $(1) 2>/dev/null | sed -n 's@^.*Build ID: \(..\)\(.*\)@\1/\2@p') + +ifneq ($$(build-id-file),) +link := $(install-dir)/.build-id/$$(build-id-file).debug + +__default: $$(link) +$$(link): $$(dest) FORCE + $$(call cmd,symlink) +endif + +endef + +$(foreach x, $(sort $(INSTALL_FILES)), $(eval $(call gen_install_rules,$(x)))) + +quiet_cmd_install = INSTALL $@ + cmd_install = mkdir -p $(dir $@); cp $< $@ + +quiet_cmd_symlink = SYMLINK $@ + cmd_symlink = mkdir -p $(dir $@); ln -sf --relative $< $@ + +PHONY += FORCE +FORCE: + +.PHONY: $(PHONY) -- cgit v1.3.1