Bugzilla – Bug 1227863
VUL-0: CVE-2024-41007: kernel: tcp: avoid too many retransmit packets
Last modified: 2024-07-17 17:40:10 UTC
In the Linux kernel, the following vulnerability has been resolved: tcp: avoid too many retransmit packets If a TCP socket is using TCP_USER_TIMEOUT, and the other peer retracted its window to zero, tcp_retransmit_timer() can retransmit a packet every two jiffies (2 ms for HZ=1000), for about 4 minutes after TCP_USER_TIMEOUT has 'expired'. The fix is to make sure tcp_rtx_probe0_timed_out() takes icsk->icsk_user_timeout into account. Before blamed commit, the socket would not timeout after icsk->icsk_user_timeout, but would use standard exponential backoff for the retransmits. Also worth noting that before commit e89688e3e978 ("net: tcp: fix unexcepted socket die when snd_wnd is 0"), the issue would last 2 minutes instead of 4. References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-41007 https://www.cve.org/CVERecord?id=CVE-2024-41007 https://git.kernel.org/stable/c/97a9063518f198ec0adb2ecb89789de342bb8283 https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2024/CVE-2024-41007.mbox