A vulnerability was found in the Linux kernel's match component in the initialization of the snd_una variable while establishing a connection. The issue arises when retransmission occurs after a fallback, leaving the snd_una sequence number uninitialized, leading to unpredictable behavior and potential denial of service.
In the Linux kernel, the following vulnerability has been resolved:
mptcp: ensure snd_una is properly initialized on connect
This is strictly related to commit fb7a0d334894 ("mptcp: ensure snd_nxt
is properly initialized on connect"). It turns out that syzkaller can
trigger the retransmit after fallback and before processing any other
incoming packet - so that snd_una is still left uninitialized.
Address the issue explicitly initializing snd_una together with snd_nxt
and write_seq.
In the Linux kernel, the following vulnerability has been resolved: mptcp: ensure snd_una is properly initialized on connect This is strictly related to commit fb7a0d334894 ("mptcp: ensure snd_nxt is properly initialized on connect"). It turns out that syzkaller can trigger the retransmit after fallback and before processing any other incoming packet - so that snd_una is still left uninitialized. Address the issue explicitly initializing snd_una together with snd_nxt and write_seq.