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| author | Shivank Garg <shivankg@amd.com> | 2026-08-22 19:22:05 +0000 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2026-09-09 17:51:44 +0530 |
| commit | e873c74132f0c5f1452816cd9bb26208f0bba1e1 (patch) | |
| tree | cc1ce1567f5b982359331863ebd9da38741f8d2e /include/net/mpls.h | |
| download | linux-stable-e873c74132f0c5f1452816cd9bb26208f0bba1e1.tar.gz linux-stable-e873c74132f0c5f1452816cd9bb26208f0bba1e1.zip | |
dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()grafted
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 <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'include/net/mpls.h')
| -rw-r--r-- | include/net/mpls.h | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/include/net/mpls.h b/include/net/mpls.h new file mode 100644 index 000000000..0bb7944e7 --- /dev/null +++ b/include/net/mpls.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2014 Nicira, Inc. + */ + +#ifndef _NET_MPLS_H +#define _NET_MPLS_H 1 + +#include <linux/if_ether.h> +#include <linux/netdevice.h> +#include <linux/mpls.h> + +#define MPLS_HLEN 4 + +struct mpls_shim_hdr { + __be32 label_stack_entry; +}; + +static inline bool eth_p_mpls(__be16 eth_type) +{ + return eth_type == htons(ETH_P_MPLS_UC) || + eth_type == htons(ETH_P_MPLS_MC); +} + +static inline struct mpls_shim_hdr *mpls_hdr(const struct sk_buff *skb) +{ + return (struct mpls_shim_hdr *)skb_network_header(skb); +} + +static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, + unsigned int ttl, + unsigned int tc, + bool bos) +{ + struct mpls_shim_hdr result; + + result.label_stack_entry = + cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) | + (tc << MPLS_LS_TC_SHIFT) | + (bos ? (1 << MPLS_LS_S_SHIFT) : 0) | + (ttl << MPLS_LS_TTL_SHIFT)); + return result; +} + +#endif |