58acd10092
syzbot reported a call trace:
BUG: KASAN: use-after-free in sctp_auth_shkey_hold+0x22/0xa0 net/sctp/auth.c:112
Call Trace:
sctp_auth_shkey_hold+0x22/0xa0 net/sctp/auth.c:112
sctp_set_owner_w net/sctp/socket.c:131 [inline]
sctp_sendmsg_to_asoc+0x152e/0x2180 net/sctp/socket.c:1865
sctp_sendmsg+0x103b/0x1d30 net/sctp/socket.c:2027
inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:821
sock_sendmsg_nosec net/socket.c:703 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:723
This is an use-after-free issue caused by not updating asoc->shkey after
it was replaced in the key list asoc->endpoint_shared_keys, and the old
key was freed.
This patch is to fix by also updating active_key for asoc when old key is
being replaced with a new one. Note that this issue doesn't exist in
sctp_auth_del_key_id(), as it's not allowed to delete the active_key
from the asoc.
Fixes: 1b1e0bc99474 ("sctp: add refcnt support for sh_key")
Reported-by: syzbot+b774577370208727d12b@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.