6.6-stable review patch. If anyone has any objections, please let me know.
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From: Gregory Detal gregory.detal@gmail.com
commit 6963c508fd7ab66ae0b7ae3db9a62ca6267f1ae8 upstream.
The current behavior is to accept any strings as inputs, this results in an inconsistent result where an unexisting scheduler can be set:
# sysctl -w net.mptcp.scheduler=notdefault net.mptcp.scheduler = notdefault
This patch changes this behavior by checking for existing scheduler before accepting the input.
Fixes: e3b2870b6d22 ("mptcp: add a new sysctl scheduler") Cc: stable@vger.kernel.org Signed-off-by: Gregory Detal gregory.detal@gmail.com Reviewed-by: Matthieu Baerts (NGI0) matttbe@kernel.org Tested-by: Geliang Tang geliang@kernel.org Reviewed-by: Mat Martineau martineau@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Link: https://lore.kernel.org/r/20240506-upstream-net-20240506-mptcp-sched-exist-v... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mptcp/ctrl.c | 39 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 38 insertions(+), 1 deletion(-)
--- a/net/mptcp/ctrl.c +++ b/net/mptcp/ctrl.c @@ -87,6 +87,43 @@ static void mptcp_pernet_set_defaults(st }
#ifdef CONFIG_SYSCTL +static int mptcp_set_scheduler(const struct net *net, const char *name) +{ + struct mptcp_pernet *pernet = mptcp_get_pernet(net); + struct mptcp_sched_ops *sched; + int ret = 0; + + rcu_read_lock(); + sched = mptcp_sched_find(name); + if (sched) + strscpy(pernet->scheduler, name, MPTCP_SCHED_NAME_MAX); + else + ret = -ENOENT; + rcu_read_unlock(); + + return ret; +} + +static int proc_scheduler(struct ctl_table *ctl, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + const struct net *net = current->nsproxy->net_ns; + char val[MPTCP_SCHED_NAME_MAX]; + struct ctl_table tbl = { + .data = val, + .maxlen = MPTCP_SCHED_NAME_MAX, + }; + int ret; + + strscpy(val, mptcp_get_scheduler(net), MPTCP_SCHED_NAME_MAX); + + ret = proc_dostring(&tbl, write, buffer, lenp, ppos); + if (write && ret == 0) + ret = mptcp_set_scheduler(net, val); + + return ret; +} + static struct ctl_table mptcp_sysctl_table[] = { { .procname = "enabled", @@ -139,7 +176,7 @@ static struct ctl_table mptcp_sysctl_tab .procname = "scheduler", .maxlen = MPTCP_SCHED_NAME_MAX, .mode = 0644, - .proc_handler = proc_dostring, + .proc_handler = proc_scheduler, }, {} };