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| author | Matthieu Baerts (NGI0) <matttbe@kernel.org> | 2024-08-28 08:14:33 +0200 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2024-08-29 10:39:50 +0200 |
| commit | 9366922adc6a71378ca01f898c41be295309f044 (patch) | |
| tree | 74dfbdc8023acc3c5b1b8485d0e2561fd7bd9341 /net | |
| parent | 58e1b66b4e4b8a602d3f2843e8eba00a969ecce2 (diff) | |
| download | linux-9366922adc6a71378ca01f898c41be295309f044.tar.gz linux-9366922adc6a71378ca01f898c41be295309f044.tar.bz2 linux-9366922adc6a71378ca01f898c41be295309f044.zip | |
mptcp: pm: fix ID 0 endp usage after multiple re-creations
'local_addr_used' and 'add_addr_accepted' are decremented for addresses
not related to the initial subflow (ID0), because the source and
destination addresses of the initial subflows are known from the
beginning: they don't count as "additional local address being used" or
"ADD_ADDR being accepted".
It is then required not to increment them when the entrypoint used by
the initial subflow is removed and re-added during a connection. Without
this modification, this entrypoint cannot be removed and re-added more
than once.
Reported-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/512
Fixes: 3ad14f54bd74 ("mptcp: more accurate MPC endpoint tracking")
Reported-by: syzbot+455d38ecd5f655fc45cf@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/00000000000049861306209237f4@google.com
Cc: stable@vger.kernel.org
Tested-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'net')
| -rw-r--r-- | net/mptcp/pm_netlink.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 3ff273e219f2..a93450ded50a 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -615,12 +615,13 @@ subflow: fullmesh = !!(local.flags & MPTCP_PM_ADDR_FLAG_FULLMESH); - msk->pm.local_addr_used++; __clear_bit(local.addr.id, msk->pm.id_avail_bitmap); /* Special case for ID0: set the correct ID */ if (local.addr.id == msk->mpc_endpoint_id) local.addr.id = 0; + else /* local_addr_used is not decr for ID 0 */ + msk->pm.local_addr_used++; nr = fill_remote_addresses_vec(msk, &local.addr, fullmesh, addrs); if (nr == 0) @@ -750,7 +751,9 @@ static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) spin_lock_bh(&msk->pm.lock); if (sf_created) { - msk->pm.add_addr_accepted++; + /* add_addr_accepted is not decr for ID 0 */ + if (remote.id) + msk->pm.add_addr_accepted++; if (msk->pm.add_addr_accepted >= add_addr_accept_max || msk->pm.subflows >= subflows_max) WRITE_ONCE(msk->pm.accept_addr, false); |