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/tests/module/Makefile | 14 ++++++++++++++ 1 file changed, 14 insertions(+) create mode 100644 lib/tests/module/Makefile (limited to 'lib/tests/module/Makefile') diff --git a/lib/tests/module/Makefile b/lib/tests/module/Makefile new file mode 100644 index 000000000..2f3e1a772 --- /dev/null +++ b/lib/tests/module/Makefile @@ -0,0 +1,14 @@ +obj-$(CONFIG_TEST_KALLSYMS_A) += test_kallsyms_a.o +obj-$(CONFIG_TEST_KALLSYMS_B) += test_kallsyms_b.o +obj-$(CONFIG_TEST_KALLSYMS_C) += test_kallsyms_c.o +obj-$(CONFIG_TEST_KALLSYMS_D) += test_kallsyms_d.o + +quiet_cmd_gen_test_kallsyms = GEN $@ + cmd_gen_test_kallsyms = $< $@ \ + $(CONFIG_TEST_KALLSYMS_NUMSYMS) \ + $(CONFIG_TEST_KALLSYMS_SCALE_FACTOR) + +$(obj)/%.c: $(src)/gen_test_kallsyms.sh FORCE + $(call if_changed,gen_test_kallsyms) + +targets += $(foreach x, a b c d, test_kallsyms_$(x).c) -- cgit v1.3.1