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/nilfs2/btnode.h | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 fs/nilfs2/btnode.h (limited to 'fs/nilfs2/btnode.h') diff --git a/fs/nilfs2/btnode.h b/fs/nilfs2/btnode.h new file mode 100644 index 000000000..4bc5612df --- /dev/null +++ b/fs/nilfs2/btnode.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * NILFS B-tree node cache + * + * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. + * + * Written by Seiji Kihara. + * Revised by Ryusuke Konishi. + */ + +#ifndef _NILFS_BTNODE_H +#define _NILFS_BTNODE_H + +#include +#include +#include +#include + +/** + * struct nilfs_btnode_chkey_ctxt - change key context + * @oldkey: old key of block's moving content + * @newkey: new key for block's content + * @bh: buffer head of old buffer + * @newbh: buffer head of new buffer + */ +struct nilfs_btnode_chkey_ctxt { + __u64 oldkey; + __u64 newkey; + struct buffer_head *bh; + struct buffer_head *newbh; +}; + +void nilfs_init_btnc_inode(struct inode *btnc_inode); +void nilfs_btnode_cache_clear(struct address_space *); +struct buffer_head *nilfs_btnode_create_block(struct address_space *btnc, + __u64 blocknr); +int nilfs_btnode_submit_block(struct address_space *, __u64, sector_t, + blk_opf_t, struct buffer_head **, sector_t *); +void nilfs_btnode_delete(struct buffer_head *); +int nilfs_btnode_prepare_change_key(struct address_space *, + struct nilfs_btnode_chkey_ctxt *); +void nilfs_btnode_commit_change_key(struct address_space *, + struct nilfs_btnode_chkey_ctxt *); +void nilfs_btnode_abort_change_key(struct address_space *, + struct nilfs_btnode_chkey_ctxt *); + +#endif /* _NILFS_BTNODE_H */ -- cgit v1.3.1