CVE-2022-49198

mptcp: Fix crash due to tcp_tsorted_anchor was initialized before release skb

Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: Fix crash due to tcp_tsorted_anchor was initialized before release skb Got crash when doing pressure test of mptcp: =========================================================================== dst_release: dst:ffffa06ce6e5c058 refcnt:-1 kernel tried to execute NX-protected page - exploit attempt? (uid: 0) BUG: unable to handle kernel paging request at ffffa06ce6e5c058 PGD 190a01067 P4D 190a01067 PUD 43fffb067 PMD 22e403063 PTE 8000000226e5c063 Oops: 0011 [#1] SMP PTI CPU: 7 PID: 7823 Comm: kworker/7:0 Kdump: loaded Tainted: G E Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.2.1 04/01/2014 Call Trace: ? skb_release_head_state+0x68/0x100 ? skb_release_all+0xe/0x30 ? kfree_skb+0x32/0xa0 ? mptcp_sendmsg_frag+0x57e/0x750 ? __mptcp_retrans+0x21b/0x3c0 ? __switch_to_asm+0x35/0x70 ? mptcp_worker+0x25e/0x320 ? process_one_work+0x1a7/0x360 ? worker_thread+0x30/0x390 ? create_worker+0x1a0/0x1a0 ? kthread+0x112/0x130 ? kthread_flush_work_fn+0x10/0x10 ? ret_from_fork+0x35/0x40 =========================================================================== In __mptcp_alloc_tx_skb skb was allocated and skb->tcp_tsorted_anchor will be initialized, in under memory pressure situation sk_wmem_schedule will return false and then kfree_skb. In this case skb->_skb_refdst is not null because_skb_refdst and tcp_tsorted_anchor are stored in the same mem, and kfree_skb will try to release dst and cause crash.

N/A

CVSS

Severity:

EPSS 0.03%

Affected: Linux Linux

References

Link	Tags
https://git.kernel.org/stable/c/af61a8f7603926c26158153d0a0755764d82657c
https://git.kernel.org/stable/c/752add6f5ce5305e55d8bda4ac8d69be3a09f14d
https://git.kernel.org/stable/c/4d54181eba4b077fb74033a7186898ad4000a7a5
https://git.kernel.org/stable/c/3ef3905aa3b5b3e222ee6eb0210bfd999417a8cc

Frequently Asked Questions

What is the severity of CVE-2022-49198?: CVE-2022-49198 has not yet been assigned a CVSS score.
How to fix CVE-2022-49198?: To fix CVE-2022-49198, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2022-49198 being actively exploited in the wild?: As for now, there are no information to confirm that CVE-2022-49198 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-49198?: CVE-2022-49198 affects Linux Linux, Linux Linux.