Re: "general protection fault in sctp_ulpevent_notify_peer_addr_change" and "general protection fault in sctp_ulpevent_nofity_peer_addr_change" should share the same root cause

[慕冬亮]

On Tue, Jan 12, 2021 at 11:27 AM Marcelo Ricardo Leitner
<marcelo.leitner@xxxxxxxxx> wrote:
>
> On Tue, Jan 12, 2021 at 10:18:00AM +0800, 慕冬亮 wrote:
> > Dear developers,
> >
> > I find that "general protection fault in l2cap_sock_getsockopt" and
> > "general protection fault in sco_sock_getsockopt" may be duplicated
> > bugs from the same root cause.
> >

I am sorry that the above description is for another bug group -
https://groups.google.com/g/syzkaller-bugs/c/csbAcYWGd2I. I forget to
modify this paragraph. Embarrassing :(

The correct description here should be, "I find that general
protection fault in sctp_ulpevent_notify_peer_addr_change" and
"general protection fault in sctp_ulpevent_nofity_peer_addr_change"
should share the same root cause, like the title.

> > First, by comparing the PoC similarity after own minimization, we find
> > they share the same PoC. Second, the stack traces for both bug reports
> > are the same except for the last function. And the different last
> > functions are due to a function name change (typo fix) from
> > "sctp_ulpevent_nofity_peer_addr_change" to
> > "sctp_ulpevent_notify_peer_addr_change"
>
> Not sure where you saw stack traces with this sctp function in it, but
> the syzkaller reports from 17 Feb 2020 are not related to SCTP.
>
> The one on sco_sock_getsockopt() seems to be lack of parameter
> validation: it doesn't check if optval is big enough when handling
> BT_PHY (which has the same value as SCTP_STATUS). It seems also miss a
> check on if level != SOL_BLUETOOTH, but I may be wrong here.
>
> l2cap_sock_getsockopt also lacks checking optlen.
>

Please ignore my mistake, and discuss the issue of
sco/l2tp_sock_getsockopt in the thread - "general protection fault in
l2cap_sock_getsockopt" and "general protection fault in
sco_sock_getsockopt" may share the same root cause
(https://groups.google.com/g/syzkaller-bugs/c/csbAcYWGd2I)


>   Marcelo