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 --- drivers/gpu/Makefile | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 drivers/gpu/Makefile (limited to 'drivers/gpu/Makefile') diff --git a/drivers/gpu/Makefile b/drivers/gpu/Makefile new file mode 100644 index 000000000..e372fc021 --- /dev/null +++ b/drivers/gpu/Makefile @@ -0,0 +1,66 @@ +# SPDX-License-Identifier: GPL-2.0-only +# drm/tegra depends on host1x, so if both drivers are built-in care must be +# taken to initialize them in the correct order. Link order is the only way +# to ensure this currently. +# Similarly, buddy must come first since it is used by other drivers. +obj-$(CONFIG_GPU_BUDDY) += buddy.o +obj-y += host1x/ drm/ vga/ tests/ +obj-$(CONFIG_IMX_IPUV3_CORE) += ipu-v3/ +obj-$(CONFIG_TRACE_GPU_MEM) += trace/ + +# nova-core and nova-drm are built from this Makefile so nova-drm's dependency +# on nova-core can be expressed as a plain Make prerequisite rather than a +# recursive sub-make. This is a temporary workaround until the Rust build +# system supports cross-crate dependencies natively. + +obj-$(CONFIG_NOVA_CORE) += nova-core.o +nova-core-y := nova-core/nova_core.o nova-core/nova_core_exports.o + +obj-$(CONFIG_DRM_NOVA) += nova-drm.o +nova-drm-y := drm/nova/nova.o + +# Export Rust symbols from nova-core only if nova-drm actually references them. +nova-core-export-deps := $(if $(CONFIG_DRM_NOVA),$(obj)/drm/nova/nova.o) + +rust_needed_exports = \ + { $(if $(strip $(2)),$(NM) -u $(2);,) echo "__DEFINED_RUST_SYMBOLS__"; \ + $(NM) -p --defined-only $(1); } | \ + awk -v fmt='$(3)' ' \ + /^__DEFINED_RUST_SYMBOLS__$$/ { defs = 1; next } \ + !defs { if ($$NF ~ /^_R/) needed[$$NF] = 1; next } \ + defs && $$2 ~ /(T|R|D|B)/ && $$3 ~ /^_R/ && \ + $$3 !~ /_(init|cleanup)_module$$/ && \ + $$3 !~ /__(pfx|cfi|odr_asan)/ && \ + $$3 in needed { printf fmt, $$3 } \ + ' + +quiet_cmd_exports = EXPORTS $@ + cmd_exports = \ + $(call rust_needed_exports,$<,$(nova-core-export-deps),EXPORT_SYMBOL_RUST_GPL(%s);\n) > $@ + +$(obj)/nova-core/exports_nova_core_generated.h: $(obj)/nova-core/nova_core.o $(nova-core-export-deps) FORCE + $(call if_changed,exports) + +targets += nova-core/exports_nova_core_generated.h + +$(obj)/nova-core/nova_core_exports.o: $(obj)/nova-core/exports_nova_core_generated.h +CFLAGS_nova-core/nova_core_exports.o := -I $(objtree)/$(obj)/nova-core + +ifdef CONFIG_MODVERSIONS +# The C export shim declares Rust symbols as `extern int`, so reuse its export +# list but generate symbol CRCs from the Rust object instead of the shim's DWARF. +$(obj)/nova-core/nova_core_exports.o: private cmd_gensymtypes_c = \ + $(call getexportsymbols,\1) | \ + $(objtree)/scripts/gendwarfksyms/gendwarfksyms \ + $(if $(KBUILD_GENDWARFKSYMS_STABLE), --stable) \ + $(if $(KBUILD_SYMTYPES), --symtypes $(@:.o=.symtypes),) \ + $(obj)/nova-core/nova_core.o +endif + +# Output nova-core's crate metadata for use by nova-drm at compile time. +RUSTFLAGS_nova-core/nova_core.o += \ + --emit=metadata=$(objtree)/$(obj)/nova-core/libnova_core.rmeta + +# Allow nova-drm to import nova-core's types. +$(obj)/drm/nova/nova.o: $(obj)/nova-core/nova_core.o +RUSTFLAGS_drm/nova/nova.o := -L $(objtree)/$(obj)/nova-core --extern nova_core -- cgit v1.3.1