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 --- net/ipv4/netlink.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 net/ipv4/netlink.c (limited to 'net/ipv4/netlink.c') diff --git a/net/ipv4/netlink.c b/net/ipv4/netlink.c new file mode 100644 index 000000000..b920e1bdc --- /dev/null +++ b/net/ipv4/netlink.c @@ -0,0 +1,33 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include +#include +#include +#include +#include + +int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family, + struct netlink_ext_ack *extack) +{ + *ip_proto = nla_get_u8(attr); + + switch (*ip_proto) { + case IPPROTO_TCP: + case IPPROTO_UDP: + return 0; + case IPPROTO_ICMP: + if (family != AF_INET) + break; + return 0; +#if IS_ENABLED(CONFIG_IPV6) + case IPPROTO_ICMPV6: + if (family != AF_INET6) + break; + return 0; +#endif + } + NL_SET_ERR_MSG(extack, "Unsupported ip proto"); + return -EOPNOTSUPP; +} +EXPORT_SYMBOL_GPL(rtm_getroute_parse_ip_proto); -- cgit v1.3.1