For the CVE-2024-26865 issue, the stable 5.15 branch code also involves this issue. However, the patch of the mainline version cannot be used on stable 5.15 branch. The commit 740ea3c4a0b2("tcp: Clean up kernel listener' s reqsk in inet_twsk_purge()") is required to stop the timer.
Eric Dumazet (1): tcp: Fix NEW_SYN_RECV handling in inet_twsk_purge()
Kuniyuki Iwashima (1): tcp: Clean up kernel listener's reqsk in inet_twsk_purge()
net/ipv4/inet_timewait_sock.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-)