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 --- lib/kunit/Makefile | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 lib/kunit/Makefile (limited to 'lib/kunit/Makefile') diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile new file mode 100644 index 000000000..204e02b10 --- /dev/null +++ b/lib/kunit/Makefile @@ -0,0 +1,34 @@ +obj-$(CONFIG_KUNIT) += kunit.o + +kunit-objs += test.o \ + resource.o \ + user_alloc.o \ + static_stub.o \ + string-stream.o \ + assert.o \ + try-catch.o \ + executor.o \ + attributes.o \ + device.o \ + platform.o \ + fwnode.o \ + bug.o + +ifeq ($(CONFIG_KUNIT_DEBUGFS),y) +kunit-objs += debugfs.o +endif + +# KUnit 'hooks' are built-in even when KUnit is built as a module. +obj-$(if $(CONFIG_KUNIT),y) += hooks.o + +obj-$(CONFIG_KUNIT_TEST) += kunit-test.o +obj-$(CONFIG_KUNIT_TEST) += platform-test.o +obj-$(CONFIG_KUNIT_TEST) += backtrace-suppression-test.o + +# string-stream-test compiles built-in only. +ifeq ($(CONFIG_KUNIT_TEST),y) +obj-$(CONFIG_KUNIT_TEST) += string-stream-test.o +obj-$(CONFIG_KUNIT_TEST) += assert_test.o +endif + +obj-$(CONFIG_KUNIT_EXAMPLE_TEST) += kunit-example-test.o -- cgit v1.3.1