linux-stable/security/selinux
Ondrej Mosnacek 3eb8eaf2ca security: implement sctp_assoc_established hook in selinux
Do this by extracting the peer labeling per-association logic from
selinux_sctp_assoc_request() into a new helper
selinux_sctp_process_new_assoc() and use this helper in both
selinux_sctp_assoc_request() and selinux_sctp_assoc_established(). This
ensures that the peer labeling behavior as documented in
Documentation/security/SCTP.rst is applied both on the client and server
side:
"""
An SCTP socket will only have one peer label assigned to it. This will be
assigned during the establishment of the first association. Any further
associations on this socket will have their packet peer label compared to
the sockets peer label, and only if they are different will the
``association`` permission be validated. This is validated by checking the
socket peer sid against the received packets peer sid to determine whether
the association should be allowed or denied.
"""

At the same time, it also ensures that the peer label of the association
is set to the correct value, such that if it is peeled off into a new
socket, the socket's peer label  will then be set to the association's
peer label, same as it already works on the server side.

While selinux_inet_conn_established() (which we are replacing by
selinux_sctp_assoc_established() for SCTP) only deals with assigning a
peer label to the connection (socket), in case of SCTP we need to also
copy the (local) socket label to the association, so that
selinux_sctp_sk_clone() can then pick it up for the new socket in case
of SCTP peeloff.

Careful readers will notice that the selinux_sctp_process_new_assoc()
helper also includes the "IPv4 packet received over an IPv6 socket"
check, even though it hadn't been in selinux_sctp_assoc_request()
before. While such check is not necessary in
selinux_inet_conn_request() (because struct request_sock's family field
is already set according to the skb's family), here it is needed, as we
don't have request_sock and we take the initial family from the socket.
In selinux_sctp_assoc_established() it is similarly needed as well (and
also selinux_inet_conn_established() already has it).

Fixes: 72e89f5008 ("security: Add support for SCTP security hooks")
Reported-by: Prashanth Prahlad <pprahlad@redhat.com>
Based-on-patch-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Tested-by: Richard Haines <richard_c_haines@btinternet.com>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-02-15 15:06:32 -05:00
..
include selinux: enclose macro arguments in parenthesis 2022-01-26 15:13:58 -05:00
ss selinux: drop unused macro 2022-01-26 16:17:18 -05:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
avc.c selinux: fix all of the W=1 build warnings 2021-10-13 16:31:51 -04:00
hooks.c security: implement sctp_assoc_established hook in selinux 2022-02-15 15:06:32 -05:00
ibpkey.c selinux: various sparse fixes 2022-02-01 19:08:28 -05:00
ima.c ima: Add digest and digest_len params to the functions to measure a buffer 2021-07-23 09:27:02 -04:00
Kconfig Documentation,selinux: deprecate setting checkreqprot to 1 2020-02-10 10:49:01 -05:00
Makefile selinux: include a consumer of the new IMA critical data hook 2021-01-14 23:41:46 -05:00
netif.c selinux: remove unused global variables 2021-01-12 09:49:01 -05:00
netlabel.c security: pass asoc to sctp_assoc_request and sctp_sk_clone 2021-11-03 11:09:20 +00:00
netlink.c selinux: mark some global variables __ro_after_init 2021-01-12 10:08:55 -05:00
netnode.c selinux: various sparse fixes 2022-02-01 19:08:28 -05:00
netport.c selinux: various sparse fixes 2022-02-01 19:08:28 -05:00
nlmsgtab.c include/uapi/linux/xfrm.h: Fix XFRM_MSG_MAPPING ABI breakage 2021-09-14 10:31:35 +02:00
selinuxfs.c selinux: check return value of sel_make_avc_files 2022-01-25 19:21:21 -05:00
status.c selinux: move status variables out of selinux_ss 2020-02-10 10:49:01 -05:00
xfrm.c selinux: Use struct_size() helper in kmalloc() 2021-12-05 21:58:32 -05:00