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 --- include/drm/intel/step.h | 62 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 include/drm/intel/step.h (limited to 'include/drm/intel/step.h') diff --git a/include/drm/intel/step.h b/include/drm/intel/step.h new file mode 100644 index 000000000..4de752010 --- /dev/null +++ b/include/drm/intel/step.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: MIT */ +/* Copyright © 2026 Intel Corporation */ + +#ifndef __STEP_H__ +#define __STEP_H__ + +#define STEP_ENUM_VAL(name) STEP_##name, + +#define STEP_NAME_LIST(func) \ + func(A0) \ + func(A1) \ + func(A2) \ + func(A3) \ + func(B0) \ + func(B1) \ + func(B2) \ + func(B3) \ + func(C0) \ + func(C1) \ + func(C2) \ + func(C3) \ + func(D0) \ + func(D1) \ + func(D2) \ + func(D3) \ + func(E0) \ + func(E1) \ + func(E2) \ + func(E3) \ + func(F0) \ + func(F1) \ + func(F2) \ + func(F3) \ + func(G0) \ + func(G1) \ + func(G2) \ + func(G3) \ + func(H0) \ + func(H1) \ + func(H2) \ + func(H3) \ + func(I0) \ + func(I1) \ + func(I2) \ + func(I3) \ + func(J0) \ + func(J1) \ + func(J2) \ + func(J3) + +/* + * Symbolic steppings that do not match the hardware. These are valid both as gt + * and display steppings as symbolic names. + */ +enum intel_step { + STEP_NONE = 0, + STEP_NAME_LIST(STEP_ENUM_VAL) + STEP_FUTURE, + STEP_FOREVER, +}; + +#endif /* __STEP_H__ */ -- cgit v1.3.1