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/crypto/cryptd.h | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 include/crypto/cryptd.h (limited to 'include/crypto/cryptd.h') diff --git a/include/crypto/cryptd.h b/include/crypto/cryptd.h new file mode 100644 index 000000000..29c5878a3 --- /dev/null +++ b/include/crypto/cryptd.h @@ -0,0 +1,39 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Software async crypto daemon + * + * Added AEAD support to cryptd. + * Authors: Tadeusz Struk (tadeusz.struk@intel.com) + * Adrian Hoban + * Gabriele Paoloni + * Aidan O'Mahony (aidan.o.mahony@intel.com) + * Copyright (c) 2010, Intel Corporation. + */ + +#ifndef _CRYPTO_CRYPT_H +#define _CRYPTO_CRYPT_H + +#include + +#include + +struct cryptd_aead { + struct crypto_aead base; +}; + +static inline struct cryptd_aead *__cryptd_aead_cast( + struct crypto_aead *tfm) +{ + return (struct cryptd_aead *)tfm; +} + +struct cryptd_aead *cryptd_alloc_aead(const char *alg_name, + u32 type, u32 mask); + +struct crypto_aead *cryptd_aead_child(struct cryptd_aead *tfm); +/* Must be called without moving CPUs. */ +bool cryptd_aead_queued(struct cryptd_aead *tfm); + +void cryptd_free_aead(struct cryptd_aead *tfm); + +#endif -- cgit v1.3.1