mptcp: fix msk traversal in mptcp_nl_cmd_set_flags()
authorPaolo Abeni <pabeni@redhat.com>
Fri, 21 Jan 2022 00:35:27 +0000 (16:35 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 8 Feb 2022 17:34:06 +0000 (18:34 +0100)
commit9908c759a17e0af6082f39c1bc1a59154ab81741
tree4c2dd323b798de169aac8eb045b9fd29f715def7
parent778283dc2840bf491de9ddc0e5d65c1449fbfc79
mptcp: fix msk traversal in mptcp_nl_cmd_set_flags()

commit 8e9eacad7ec7a9cbf262649ebf1fa6e6f6cc7d82 upstream.

The MPTCP endpoint list is under RCU protection, guarded by the
pernet spinlock. mptcp_nl_cmd_set_flags() traverses the list
without acquiring the spin-lock nor under the RCU critical section.

This change addresses the issue performing the lookup and the endpoint
update under the pernet spinlock.

[The upstream commit had to handle a lookup_by_id variable that is only
 present in 5.17. This version of the patch removes that variable, so
 the __lookup_addr() function only handles the lookup as it is
 implemented in 5.15 and 5.16. It also removes one 'const' keyword to
 prevent a warning due to differing const-ness in the 5.17 version of
 addresses_equal().]

Fixes: 0f9f696a502e ("mptcp: add set_flags command in PM netlink")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/mptcp/pm_netlink.c