一、漏洞信息
漏洞编号：CVE-2025-40064
漏洞归属组件：kernel
漏洞归属的版本：4.19.140,4.19.194,4.19.90,5.10.0,6.1.19,6.12.33,6.18.18,6.18.40,6.4.0,6.6.0
CVSS评分：
BaseScore：7.8 High
Vector：CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
漏洞简述：
In the Linux kernel, the following vulnerability has been resolved:smc: Fix use-after-free in __pnet_find_base_ndev().syzbot reported use-after-free of net_device in __pnet_find_base_ndev(),which was called during connect(). [0]smc_pnet_find_ism_resource() fetches sk_dst_get(sk)->dev and passesdown to pnet_find_base_ndev(), where RTNL is held. Then, UAF happenedat __pnet_find_base_ndev() when the dev is first used.This means dev had already been freed before acquiring RTNL inpnet_find_base_ndev().While dev is going away, dst->dev could be swapped with blackhole_netdev,and the dev s refcnt by dst will be released.We must hold dev s refcnt before calling smc_pnet_find_ism_resource().Also, smc_pnet_find_roce_resource() has the same problem.Let s use __sk_dst_get() and dst_dev_rcu() in the two functions.[0]:BUG: KASAN: use-after-free in __pnet_find_base_ndev+0x1b1/0x1c0 net/smc/smc_pnet.c:926Read of size 1 at addr ffff888036bac33a by task syz.0.3632/18609CPU: 1 UID: 0 PID: 18609 Comm: syz.0.3632 Not tainted syzkaller #0 PREEMPT(full)Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __pnet_find_base_ndev+0x1b1/0x1c0 net/smc/smc_pnet.c:926 pnet_find_base_ndev net/smc/smc_pnet.c:946 [inline] smc_pnet_find_ism_by_pnetid net/smc/smc_pnet.c:1103 [inline] smc_pnet_find_ism_resource+0xef/0x390 net/smc/smc_pnet.c:1154 smc_find_ism_device net/smc/af_smc.c:1030 [inline] smc_find_proposal_devices net/smc/af_smc.c:1115 [inline] __smc_connect+0x372/0x1890 net/smc/af_smc.c:1545 smc_connect+0x877/0xd90 net/smc/af_smc.c:1715 __sys_connect_file net/socket.c:2086 [inline] __sys_connect+0x313/0x440 net/socket.c:2105 __do_sys_connect net/socket.c:2111 [inline] __se_sys_connect net/socket.c:2108 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2108 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7fRIP: 0033:0x7f47cbf8eba9Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48RSP: 002b:00007f47ccdb1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002aRAX: ffffffffffffffda RBX: 00007f47cc1d5fa0 RCX: 00007f47cbf8eba9RDX: 0000000000000010 RSI: 0000200000000280 RDI: 000000000000000bRBP: 00007f47cc011e19 R08: 0000000000000000 R09: 0000000000000000R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000R13: 00007f47cc1d6038 R14: 00007f47cc1d5fa0 R15: 00007ffc512f8aa8 The buggy address belongs to the physical page:page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888036bacd00 pfn:0x36bacflags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)raw: 00fff00000000000 ffffea0001243d08 ffff8880b863fdc0 0000000000000000raw: ffff888036bacd00 0000000000000000 00000000ffffffff 0000000000000000page dumped because: kasan: bad access detectedpage_owner tracks the page as freedpage last allocated via order 2, migratetype Unmovable, gfp_mask 0x446dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP), pid 16741, tgid 16741 (syz-executor), ts 343313197788, free_ts 380670750466 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 ___kmalloc_large_node+0x5f/0x1b0 mm/slub.c:4317 __kmalloc_large_node_noprof+0x18/0x90 mm/slub.c:4348 __do_kmalloc_node mm/slub.c:4364 [inline] __kvmalloc_node---truncated---
漏洞公开时间：2025-10-28 20:15:40
漏洞创建时间：2025-10-28 20:45:35
漏洞详情参考链接：
https://nvd.nist.gov/vuln/detail/CVE-2025-40064

漏洞分析指导链接：
https://atomgit.com/openeuler/cve-manager/blob/master/cve-vulner-manager/doc/md/manual.md
漏洞数据来源:
七彩瞬析开源风险感知平台
漏洞补丁信息：

二、漏洞分析结构反馈
影响性分析说明：
In the Linux kernel, the following vulnerability has been resolved:smc: Fix use-after-free in __pnet_find_base_ndev().syzbot reported use-after-free of net_device in __pnet_find_base_ndev(),which was called during connect(). [0]smc_pnet_find_ism_resource() fetches sk_dst_get(sk)->dev and passesdown to pnet_find_base_ndev(), where RTNL is held. Then, UAF happenedat __pnet_find_base_ndev() when the dev is first used.This means dev had already been freed before acquiring RTNL inpnet_find_base_ndev().While dev is going away, dst->dev could be swapped with blackhole_netdev,and the dev's refcnt by dst will be released.We must hold dev's refcnt before calling smc_pnet_find_ism_resource().Also, smc_pnet_find_roce_resource() has the same problem.Let's use __sk_dst_get() and dst_dev_rcu() in the two functions.[0]:BUG: KASAN: use-after-free in __pnet_find_base_ndev+0x1b1/0x1c0 net/smc/smc_pnet.c:926Read of size 1 at addr ffff888036bac33a by task syz.0.3632/18609CPU: 1 UID: 0 PID: 18609 Comm: syz.0.3632 Not tainted syzkaller #0 PREEMPT(full)Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __pnet_find_base_ndev+0x1b1/0x1c0 net/smc/smc_pnet.c:926 pnet_find_base_ndev net/smc/smc_pnet.c:946 [inline] smc_pnet_find_ism_by_pnetid net/smc/smc_pnet.c:1103 [inline] smc_pnet_find_ism_resource+0xef/0x390 net/smc/smc_pnet.c:1154 smc_find_ism_device net/smc/af_smc.c:1030 [inline] smc_find_proposal_devices net/smc/af_smc.c:1115 [inline] __smc_connect+0x372/0x1890 net/smc/af_smc.c:1545 smc_connect+0x877/0xd90 net/smc/af_smc.c:1715 __sys_connect_file net/socket.c:2086 [inline] __sys_connect+0x313/0x440 net/socket.c:2105 __do_sys_connect net/socket.c:2111 [inline] __se_sys_connect net/socket.c:2108 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2108 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7fRIP: 0033:0x7f47cbf8eba9Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48RSP: 002b:00007f47ccdb1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002aRAX: ffffffffffffffda RBX: 00007f47cc1d5fa0 RCX: 00007f47cbf8eba9RDX: 0000000000000010 RSI: 0000200000000280 RDI: 000000000000000bRBP: 00007f47cc011e19 R08: 0000000000000000 R09: 0000000000000000R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000R13: 00007f47cc1d6038 R14: 00007f47cc1d5fa0 R15: 00007ffc512f8aa8 </TASK>The buggy address belongs to the physical page:page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888036bacd00 pfn:0x36bacflags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)raw: 00fff00000000000 ffffea0001243d08 ffff8880b863fdc0 0000000000000000raw: ffff888036bacd00 0000000000000000 00000000ffffffff 0000000000000000page dumped because: kasan: bad access detectedpage_owner tracks the page as freedpage last allocated via order 2, migratetype Unmovable, gfp_mask 0x446dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP), pid 16741, tgid 16741 (syz-executor), ts 343313197788, free_ts 380670750466 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 ___kmalloc_large_node+0x5f/0x1b0 mm/slub.c:4317 __kmalloc_large_node_noprof+0x18/0x90 mm/slub.c:4348 __do_kmalloc_node mm/slub.c:4364 [inline] __kvmalloc_node_noprof+0x6d/0x5f0 mm/slub.c:5067 alloc_netdev_mqs+0xa3/0x11b0 net/core/dev.c:11812 tun_set_iff+0x532/0xef0 drivers/net/tun.c:2775 __tun_chr_ioctl+0x788/0x1
openEuler评分：
7.1
Vector：CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
受影响版本排查(受影响/不受影响)：
1.master(6.18.40):不受影响
2.openEuler-20.03-LTS-SP4(4.19.90):受影响
3.openEuler-22.03-LTS-SP3(5.10.0):受影响
4.openEuler-22.03-LTS-SP4(5.10.0):受影响
5.openEuler-24.03-LTS(6.6.0):受影响
6.openEuler-24.03-LTS-Next(6.6.0):不受影响
7.openEuler-24.03-LTS-SP1(6.6.0):受影响
8.openEuler-24.03-LTS-SP2(6.6.0):受影响
9.openEuler-24.03-LTS-SP3(6.6.0):受影响
10.openEuler-24.03-LTS-SP4(6.6.0):受影响

修复是否涉及abi变化(是/否)：
1.master(6.18.40):否
2.openEuler-20.03-LTS-SP4(4.19.90):否
3.openEuler-22.03-LTS-SP3(5.10.0):否
4.openEuler-22.03-LTS-SP4(5.10.0):否
5.openEuler-24.03-LTS(6.6.0):否
6.openEuler-24.03-LTS-Next(6.6.0):否
7.openEuler-24.03-LTS-SP1(6.6.0):否
8.openEuler-24.03-LTS-SP2(6.6.0):否
9.openEuler-24.03-LTS-SP3(6.6.0):否
10.openEuler-24.03-LTS-SP4(6.6.0):否

原因说明：
1.master(6.18.40):不受影响-漏洞代码不能被攻击者触发
2.openEuler-20.03-LTS-SP4(4.19.90):暂不修复-暂无解决方案或补丁
3.openEuler-22.03-LTS-SP3(5.10.0):不修复-超出修复范围
4.openEuler-22.03-LTS-SP4(5.10.0):不修复-超出修复范围
5.openEuler-24.03-LTS(6.6.0):不修复-超出修复范围
6.openEuler-24.03-LTS-Next(6.6.0):不受影响-漏洞代码不能被攻击者触发
7.openEuler-24.03-LTS-SP1(6.6.0):漏洞仍在分析中
8.openEuler-24.03-LTS-SP2(6.6.0):不修复-超出修复范围
9.openEuler-24.03-LTS-SP3(6.6.0):漏洞仍在分析中
10.openEuler-24.03-LTS-SP4(6.6.0):漏洞仍在分析中