From ${URL}: Description of the problem: For a TCP-style socket, while processing the COOKIE_ECHO chunk in sctp_sf_do_5_1D_ce(), after it has passed a series of sanity check, a new association would be created in sctp_unpack_cookie(), but afterwards, some processing maybe failed, and sctp_association_free() will be called to free the previously allocated association, in sctp_association_free(), sk_ack_backlog value is decremented for this socket, since the initial value for sk_ack_backlog is 0, after the decrement, it will be 65535, a wrap-around problem happens, and if we want to establish new associations afterward in the same socket, ABORT would be triggered since sctp deem the accept queue as full. A remote attacker can block further connection to the particular sctp server socket by sending a specially crafted sctp packet. Upstream patch: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d3217b15a19a4779c39b212358a5c71d725822ee References: https://bugzilla.redhat.com/show_bug.cgi?id=1113967
CVE-2014-4667 (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2014-4667): The sctp_association_free function in net/sctp/associola.c in the Linux kernel before 3.15.2 does not properly manage a certain backlog value, which allows remote attackers to cause a denial of service (socket outage) via a crafted SCTP packet.
Fix in 3.16
