From: Eric Dumazet <[email protected]>
Date: Wed, 11 Apr 2018 14:36:28 -0700
> syzbot/KMSAN reported an uninit-value in tcp_parse_options() [1]
>
> I believe this was caused by a TCP_MD5SIG being set on live
> flow.
>
> This is highly unexpected, since TCP option space is limited.
>
> For instance, presence of TCP MD5 option automatically disables
> TCP TimeStamp option at SYN/SYNACK time, which we can not do
> once flow has been established.
>
> Really, adding/deleting an MD5 key only makes sense on sockets
> in CLOSE or LISTEN state.
...
> Fixes: cfb6eeb4c860 ("[TCP]: MD5 Signature Option (RFC2385) support.")
> Signed-off-by: Eric Dumazet <[email protected]>
> Reported-by: syzbot <[email protected]>
Applied and queued up for -stable.