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/net/esp.h | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 include/net/esp.h (limited to 'include/net/esp.h') diff --git a/include/net/esp.h b/include/net/esp.h new file mode 100644 index 000000000..322950727 --- /dev/null +++ b/include/net/esp.h @@ -0,0 +1,50 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _NET_ESP_H +#define _NET_ESP_H + +#include + +struct ip_esp_hdr; +struct xfrm_state; + +static inline struct ip_esp_hdr *ip_esp_hdr(const struct sk_buff *skb) +{ + return (struct ip_esp_hdr *)skb_transport_header(skb); +} + +static inline void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) +{ + /* Fill padding... */ + if (tfclen) { + memset(tail, 0, tfclen); + tail += tfclen; + } + do { + int i; + for (i = 0; i < plen - 2; i++) + tail[i] = i + 1; + } while (0); + tail[plen - 2] = plen - 2; + tail[plen - 1] = proto; +} + +struct esp_info { + struct ip_esp_hdr *esph; + __be64 seqno; + int tfclen; + int tailen; + int plen; + int clen; + int len; + int nfrags; + __u8 proto; + bool inplace; +}; + +int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp); +int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp); +int esp_input_done2(struct sk_buff *skb, int err); +int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp); +int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp); +int esp6_input_done2(struct sk_buff *skb, int err); +#endif -- cgit v1.3.1