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/btrfs/dev-replace.h | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 fs/btrfs/dev-replace.h (limited to 'fs/btrfs/dev-replace.h') diff --git a/fs/btrfs/dev-replace.h b/fs/btrfs/dev-replace.h new file mode 100644 index 000000000..b35cecf38 --- /dev/null +++ b/fs/btrfs/dev-replace.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) STRATO AG 2012. All rights reserved. + */ + +#ifndef BTRFS_DEV_REPLACE_H +#define BTRFS_DEV_REPLACE_H + +#include +#include + +struct btrfs_ioctl_dev_replace_args; +struct btrfs_fs_info; +struct btrfs_trans_handle; +struct btrfs_dev_replace; +struct btrfs_block_group; +struct btrfs_device; + +int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info); +int btrfs_run_dev_replace(struct btrfs_trans_handle *trans); +int btrfs_dev_replace_by_ioctl(struct btrfs_fs_info *fs_info, + struct btrfs_ioctl_dev_replace_args *args); +void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info, + struct btrfs_ioctl_dev_replace_args *args); +int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info); +void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info); +int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info); +bool __pure btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace); +bool btrfs_finish_block_group_to_copy(struct btrfs_device *srcdev, + struct btrfs_block_group *cache, + u64 physical); +void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info); +void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount); + +static inline void btrfs_bio_counter_dec(struct btrfs_fs_info *fs_info) +{ + btrfs_bio_counter_sub(fs_info, 1); +} + + +#endif -- cgit v1.3.1