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 --- fs/dlm/lockspace.h | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 fs/dlm/lockspace.h (limited to 'fs/dlm/lockspace.h') diff --git a/fs/dlm/lockspace.h b/fs/dlm/lockspace.h new file mode 100644 index 000000000..47ebd4411 --- /dev/null +++ b/fs/dlm/lockspace.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** +******************************************************************************* +******************************************************************************/ + +#ifndef __LOCKSPACE_DOT_H__ +#define __LOCKSPACE_DOT_H__ + +/* DLM_LSFL_FS + * The lockspace user is in the kernel (i.e. filesystem). Enables + * direct bast/cast callbacks. + * + * internal lockspace flag - will be removed in future + */ +#define DLM_LSFL_FS 0x00000004 + +int dlm_lockspace_init(void); +void dlm_lockspace_exit(void); +struct dlm_ls *dlm_find_lockspace_global(uint32_t id); +struct dlm_ls *dlm_find_lockspace_local(void *id); +struct dlm_ls *dlm_find_lockspace_device(int minor); +void dlm_put_lockspace(struct dlm_ls *ls); +void dlm_stop_lockspaces(void); +int dlm_new_user_lockspace(const char *name, const char *cluster, + uint32_t flags, int lvblen, + const struct dlm_lockspace_ops *ops, + void *ops_arg, int *ops_result, + dlm_lockspace_t **lockspace); + +#endif /* __LOCKSPACE_DOT_H__ */ + -- cgit v1.3.1