Subject: Re: [PATCH net 3/3] sch_cake: Fix out of bounds when parsing TCP options

From: Toke Høiland-Jørgensen <[email-masked]>
Date: Wed, 09 Jun 2021 23:51:23 +0200

Maxim Mikityanskiy <[email-masked]> writes:

> The TCP option parser in cake qdisc (cake_get_tcpopt and
> cake_tcph_may_drop) could read one byte out of bounds. When the length
> is 1, the execution flow gets into the loop, reads one byte of the
> opcode, and if the opcode is neither TCPOPT_EOL nor TCPOPT_NOP, it reads
> one more byte, which exceeds the length of 1.
>
> This fix is inspired by commit 9609dad263f8 ("ipv4: tcp_input: fix stack
> out of bounds when parsing TCP options.").
>
> Cc: Young Xiao <[email-masked]>
> Fixes: 8b7138814f29 ("sch_cake: Add optional ACK filter")
> Signed-off-by: Maxim Mikityanskiy <[email-masked]>

Thanks for fixing this!

Acked-by: Toke Høiland-Jørgensen <[email-masked]>