maxmustermann/linux
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

mptcp: add accept_subflow re-check

Browse source 
The re-check of pm->accept_subflow with pm->lock held was missing, this
patch fixed it.

Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Geliang Tang 2020-09-24 08:29:53 +08:00 committed by David S. Miller
parent be61316003
commit f58f065aa1
1 changed files with 6 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
net/mptcp/pm.c
View file

@ -48,7 +48,7 @@ void mptcp_pm_new_connection(struct mptcp_sock *msk, int server_side)
bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk)
{
struct mptcp_pm_data *pm = &msk->pm;
int ret;
int ret = 0;
pr_debug("msk=%p subflows=%d max=%d allow=%d", msk, pm->subflows,
pm->subflows_max, READ_ONCE(pm->accept_subflow));
@ -58,9 +58,11 @@ bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk)
return false;
spin_lock_bh(&pm->lock);
ret = pm->subflows < pm->subflows_max;
if (ret && ++pm->subflows == pm->subflows_max)
WRITE_ONCE(pm->accept_subflow, false);
if (READ_ONCE(pm->accept_subflow)) {
ret = pm->subflows < pm->subflows_max;
if (ret && ++pm->subflows == pm->subflows_max)
WRITE_ONCE(pm->accept_subflow, false);
}
spin_unlock_bh(&pm->lock);
return ret;