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/rdma/ib_cache.h | 101 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 include/rdma/ib_cache.h (limited to 'include/rdma/ib_cache.h') diff --git a/include/rdma/ib_cache.h b/include/rdma/ib_cache.h new file mode 100644 index 000000000..eed46d966 --- /dev/null +++ b/include/rdma/ib_cache.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */ +/* + * Copyright (c) 2004 Topspin Communications. All rights reserved. + * Copyright (c) 2005 Intel Corporation. All rights reserved. + * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved. + */ + +#ifndef _IB_CACHE_H +#define _IB_CACHE_H + +#include + +int rdma_query_gid(struct ib_device *device, u32 port_num, int index, + union ib_gid *gid); +void *rdma_read_gid_hw_context(const struct ib_gid_attr *attr); +const struct ib_gid_attr *rdma_find_gid(struct ib_device *device, + const union ib_gid *gid, + enum ib_gid_type gid_type, + struct net_device *ndev); +const struct ib_gid_attr *rdma_find_gid_by_port(struct ib_device *ib_dev, + const union ib_gid *gid, + enum ib_gid_type gid_type, + u32 port, + struct net_device *ndev); +const struct ib_gid_attr *rdma_find_gid_by_filter( + struct ib_device *device, const union ib_gid *gid, u32 port_num, + bool (*filter)(const union ib_gid *gid, const struct ib_gid_attr *, + void *), + void *context); + +int rdma_read_gid_l2_fields(const struct ib_gid_attr *attr, + u16 *vlan_id, u8 *smac); +struct net_device *rdma_read_gid_attr_ndev_rcu(const struct ib_gid_attr *attr); + +/** + * ib_get_cached_pkey - Returns a cached PKey table entry + * @device_handle: The device to query. + * @port_num: The port number of the device to query. + * @index: The index into the cached PKey table to query. + * @pkey: The PKey value found at the specified index. + * + * ib_get_cached_pkey() fetches the specified PKey table entry stored in + * the local software cache. + */ +int ib_get_cached_pkey(struct ib_device *device_handle, + u32 port_num, + int index, + u16 *pkey); + +/** + * ib_find_cached_pkey - Returns the PKey table index where a specified + * PKey value occurs. + * @device: The device to query. + * @port_num: The port number of the device to search for the PKey. + * @pkey: The PKey value to search for. + * @index: The index into the cached PKey table where the PKey was found. + * + * ib_find_cached_pkey() searches the specified PKey table in + * the local software cache. + */ +int ib_find_cached_pkey(struct ib_device *device, + u32 port_num, + u16 pkey, + u16 *index); + +/** + * ib_get_cached_lmc - Returns a cached lmc table entry + * @device: The device to query. + * @port_num: The port number of the device to query. + * @lmc: The lmc value for the specified port for that device. + * + * ib_get_cached_lmc() fetches the specified lmc table entry stored in + * the local software cache. + */ +int ib_get_cached_lmc(struct ib_device *device, + u32 port_num, + u8 *lmc); + +/** + * ib_get_cached_port_state - Returns a cached port state table entry + * @device: The device to query. + * @port_num: The port number of the device to query. + * @port_active: port_state for the specified port for that device. + * + * ib_get_cached_port_state() fetches the specified port_state table entry stored in + * the local software cache. + */ +int ib_get_cached_port_state(struct ib_device *device, + u32 port_num, + enum ib_port_state *port_active); + +bool rdma_is_zero_gid(const union ib_gid *gid); +const struct ib_gid_attr *rdma_get_gid_attr(struct ib_device *device, + u32 port_num, int index); +void rdma_put_gid_attr(const struct ib_gid_attr *attr); +void rdma_hold_gid_attr(const struct ib_gid_attr *attr); +ssize_t rdma_query_gid_table(struct ib_device *device, + struct ib_uverbs_gid_entry *entries, + size_t max_entries); + +#endif /* _IB_CACHE_H */ -- cgit v1.3.1