bianbu-repo-mirror/bianbu-linux-6.6
1
0
Fork 0
mirror of https://gitee.com/bianbu-linux/linux-6.6 synced 2025-04-24 14:07:52 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

mptcp: pm: only mark 'subflow' endp as available

Browse source 
commit 322ea3778965da72862cca2a0c50253aacf65fe6 upstream.

Adding the following warning ...

  WARN_ON_ONCE(msk->pm.local_addr_used == 0)

... before decrementing the local_addr_used counter helped to find a bug
when running the "remove single address" subtest from the mptcp_join.sh
selftests.

Removing a 'signal' endpoint will trigger the removal of all subflows
linked to this endpoint via mptcp_pm_nl_rm_addr_or_subflow() with
rm_type == MPTCP_MIB_RMSUBFLOW. This will decrement the local_addr_used
counter, which is wrong in this case because this counter is linked to
'subflow' endpoints, and here it is a 'signal' endpoint that is being
removed.

Now, the counter is decremented, only if the ID is being used outside
of mptcp_pm_nl_rm_addr_or_subflow(), only for 'subflow' endpoints, and
if the ID is not 0 -- local_addr_used is not taking into account these
ones. This marking of the ID as being available, and the decrement is
done no matter if a subflow using this ID is currently available,
because the subflow could have been closed before.

Fixes: 06faa22710 ("mptcp: remove multi addresses and subflows in PM")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240819-net-mptcp-pm-reusing-id-v1-8-38035d40de5b@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Matthieu Baerts (NGI0) 2024-08-19 21:45:26 +02:00 • committed by Greg Kroah-Hartman
parent 01db518468
commit 43cf912b0b
1 changed files with 17 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

26
net/mptcp/pm_netlink.c
View file

@ -841,10 +841,10 @@ static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
if (rm_type == MPTCP_MIB_RMSUBFLOW) if (rm_type == MPTCP_MIB_RMSUBFLOW)
__MPTCP_INC_STATS(sock_net(sk), rm_type); __MPTCP_INC_STATS(sock_net(sk), rm_type);
} }
if (rm_type == MPTCP_MIB_RMSUBFLOW)
__set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap); if (rm_type == MPTCP_MIB_RMADDR)
else if (rm_type == MPTCP_MIB_RMADDR)
__MPTCP_INC_STATS(sock_net(sk), rm_type); __MPTCP_INC_STATS(sock_net(sk), rm_type);
if (!removed) if (!removed)
continue; continue;
@ -854,8 +854,6 @@ static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
if (rm_type == MPTCP_MIB_RMADDR) { if (rm_type == MPTCP_MIB_RMADDR) {
msk->pm.add_addr_accepted--; msk->pm.add_addr_accepted--;
WRITE_ONCE(msk->pm.accept_addr, true); WRITE_ONCE(msk->pm.accept_addr, true);
} else if (rm_type == MPTCP_MIB_RMSUBFLOW) {
msk->pm.local_addr_used--;
} }
} }
} }
@ -1472,6 +1470,14 @@ static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
return ret; return ret;
} }
static void __mark_subflow_endp_available(struct mptcp_sock *msk, u8 id)
{
/* If it was marked as used, and not ID 0, decrement local_addr_used */
if (!__test_and_set_bit(id ? : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap) &&
id && !WARN_ON_ONCE(msk->pm.local_addr_used == 0))
msk->pm.local_addr_used--;
}
static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
const struct mptcp_pm_addr_entry *entry) const struct mptcp_pm_addr_entry *entry)
{ {
@ -1505,11 +1511,11 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
spin_lock_bh(&msk->pm.lock); spin_lock_bh(&msk->pm.lock);
mptcp_pm_nl_rm_subflow_received(msk, &list); mptcp_pm_nl_rm_subflow_received(msk, &list);
spin_unlock_bh(&msk->pm.lock); spin_unlock_bh(&msk->pm.lock);
} else if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { }
/* If the subflow has been used, but now closed */
if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
spin_lock_bh(&msk->pm.lock); spin_lock_bh(&msk->pm.lock);
if (!__test_and_set_bit(entry->addr.id, msk->pm.id_avail_bitmap)) __mark_subflow_endp_available(msk, list.ids[0]);
msk->pm.local_addr_used--;
spin_unlock_bh(&msk->pm.lock); spin_unlock_bh(&msk->pm.lock);
} }
@ -1547,6 +1553,7 @@ static int mptcp_nl_remove_id_zero_address(struct net *net,
spin_lock_bh(&msk->pm.lock); spin_lock_bh(&msk->pm.lock);
mptcp_pm_remove_addr(msk, &list); mptcp_pm_remove_addr(msk, &list);
mptcp_pm_nl_rm_subflow_received(msk, &list); mptcp_pm_nl_rm_subflow_received(msk, &list);
__mark_subflow_endp_available(msk, 0);
spin_unlock_bh(&msk->pm.lock); spin_unlock_bh(&msk->pm.lock);
release_sock(sk); release_sock(sk);
@ -1939,6 +1946,7 @@ static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk,
spin_lock_bh(&msk->pm.lock); spin_lock_bh(&msk->pm.lock);
mptcp_pm_nl_rm_subflow_received(msk, &list); mptcp_pm_nl_rm_subflow_received(msk, &list);
__mark_subflow_endp_available(msk, list.ids[0]);
mptcp_pm_create_subflow_or_signal_addr(msk); mptcp_pm_create_subflow_or_signal_addr(msk);
spin_unlock_bh(&msk->pm.lock); spin_unlock_bh(&msk->pm.lock);
} }