CVE-2024-40959: xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr()
In the Linux kernel, the following vulnerability has been resolved:
xfrm6: check ip6dstidev() return value in xfrm6getsaddr()
ip6dstidev() can return NULL, xfrm6getsaddr() must act accordingly.
syzbot reported:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 12 Comm: kworker/u8:1 Not tainted 6.10.0-rc2-syzkaller-00383-gb8481381d4e2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: wg-kex-wg1 wgpackethandshakesendworker RIP: 0010:xfrm6getsaddr+0x93/0x130 net/ipv6/xfrm6policy.c:64 Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 97 00 00 00 4c 8b ab d8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 86 00 00 00 4d 8b 6d 00 e8 ca 13 47 01 48 b8 00 RSP: 0018:ffffc90000117378 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88807b079dc0 RCX: ffffffff89a0d6d7 RDX: 0000000000000000 RSI: ffffffff89a0d6e9 RDI: ffff88807b079e98 RBP: ffff88807ad73248 R08: 0000000000000007 R09: fffffffffffff000 R10: ffff88807b079dc0 R11: 0000000000000007 R12: ffffc90000117480 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4586d00440 CR3: 0000000079042000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> xfrmgetsaddr net/xfrm/xfrmpolicy.c:2452 [inline] xfrmtmplresolveone net/xfrm/xfrmpolicy.c:2481 [inline] xfrmtmplresolve+0xa26/0xf10 net/xfrm/xfrmpolicy.c:2541 xfrmresolveandcreatebundle+0x140/0x2570 net/xfrm/xfrmpolicy.c:2835 xfrmbundlelookup net/xfrm/xfrmpolicy.c:3070 [inline] xfrmlookupwithifid+0x4d1/0x1e60 net/xfrm/xfrmpolicy.c:3201 xfrmlookup net/xfrm/xfrmpolicy.c:3298 [inline] xfrmlookuproute+0x3b/0x200 net/xfrm/xfrmpolicy.c:3309 ip6dstlookupflow+0x15c/0x1d0 net/ipv6/ip6output.c:1256 send6+0x611/0xd20 drivers/net/wireguard/socket.c:139 wgsocketsendskbtopeer+0xf9/0x220 drivers/net/wireguard/socket.c:178 wgsocketsendbuffertopeer+0x12b/0x190 drivers/net/wireguard/socket.c:200 wgpacketsendhandshakeinitiation+0x227/0x360 drivers/net/wireguard/send.c:40 wgpackethandshakesendworker+0x1c/0x30 drivers/net/wireguard/send.c:51 processonework+0x9fb/0x1b60 kernel/workqueue.c:3231 processscheduledworks kernel/workqueue.c:3312 [inline] workerthread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 retfromfork+0x45/0x80 arch/x86/kernel/process.c:147 retfromforkasm+0x1a/0x30 arch/x86/entry/entry64.S:244
Other sources
Linux Kernel is vulnerable to a denial of service, caused by a Null pointer dereference xfrm6getsaddr() ip6dstidev(). A local authenticated attacker could exploit this vulnerability to cause a denial of service.
— IBM
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-40959?
The severity of CVE-2024-40959 is not explicitly stated in common scoring systems, but it does address a general protection fault issue in the Linux kernel.
How do I fix CVE-2024-40959?
To fix CVE-2024-40959, update the Linux kernel to versions 4.19.317, 5.4.279, 5.10.221, 5.15.162, 6.1.96, 6.6.36, 6.9.7, or 6.10 as specified in the advisory.
Which Linux kernel versions are affected by CVE-2024-40959?
CVE-2024-40959 affects multiple Linux kernel versions ranging from 2.6.12 up to 6.10-rc4.
Is my system vulnerable to CVE-2024-40959 if I use Red Hat kernel?
Yes, systems using Red Hat kernel versions below the remedied versions are vulnerable to CVE-2024-40959.
What problem does CVE-2024-40959 address in the Linux kernel?
CVE-2024-40959 addresses a potential general protection fault caused by the ip6_dst_idev() function returning NULL and the xfrm6_get_saddr() function needing to handle it properly.