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/raid/raid6/algos.h | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 lib/raid/raid6/algos.h (limited to 'lib/raid/raid6/algos.h') diff --git a/lib/raid/raid6/algos.h b/lib/raid/raid6/algos.h new file mode 100644 index 000000000..43f636be1 --- /dev/null +++ b/lib/raid/raid6/algos.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright 2003 H. Peter Anvin - All Rights Reserved + */ +#ifndef _PQ_IMPL_H +#define _PQ_IMPL_H + +#include +#include + +/* Routine choices */ +struct raid6_calls { + const char *name; + void (*gen_syndrome)(int disks, size_t bytes, void **ptrs); + void (*xor_syndrome)(int disks, int start, int stop, size_t bytes, + void **ptrs); +}; + +struct raid6_recov_calls { + const char *name; + void (*data2)(int disks, size_t bytes, int faila, int failb, + void **ptrs); + void (*datap)(int disks, size_t bytes, int faila, void **ptrs); +}; + +void __init raid6_algo_add(const struct raid6_calls *algo); +void __init raid6_algo_add_default(void); +void __init raid6_recov_algo_add(const struct raid6_recov_calls *algo); + +/* for the kunit test */ +const struct raid6_calls *raid6_algo_find(unsigned int idx); +const struct raid6_recov_calls *raid6_recov_algo_find(unsigned int idx); + +/* generic implementations */ +extern const struct raid6_calls raid6_intx1; +extern const struct raid6_calls raid6_intx2; +extern const struct raid6_calls raid6_intx4; +extern const struct raid6_calls raid6_intx8; +extern const struct raid6_recov_calls raid6_recov_intx1; + +#endif /* _PQ_IMPL_H */ -- cgit v1.3.1