RE: [PATCH net v2 1/4] dpll: fix pin dump crash after module unbind

From: Jiri Pirko <jiri@resnulli.us>
Sent: Thursday, January 4, 2024 4:09 PM

Thu, Jan 04, 2024 at 12:11:29PM CET, arkadiusz.kubalewski@intel.com wrote:

quoted

Disallow dump of unregistered parent pins, it is possible when parent
pin and dpll device registerer kernel module instance unbinds, and
other kernel module instances of the same dpll device have pins
registered with the parent pin. The user can invoke a pin-dump but as
the parent was unregistered, those shall not be accessed by the
userspace, prevent that by checking if parent pin is still registered.

Fixes: 9d71b54b65b1 ("dpll: netlink: Add DPLL framework base functions")
Reviewed-by: Jan Glaza <redacted>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
---
drivers/dpll/dpll_netlink.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
index ce7cf736f020..b53478374a38 100644
--- a/drivers/dpll/dpll_netlink.c
+++ b/drivers/dpll/dpll_netlink.c

@@ -328,6 +328,8 @@ dpll_msg_add_pin_parents(struct sk_buff *msg, struct

dpll_pin *pin,
		void *parent_priv;

		ppin = ref->pin;
+		if (!xa_get_mark(&dpll_pin_xa, ppin->id, DPLL_REGISTERED))
+			continue;

If you make sure to hide the pin properly with the last patch, you don't
need this one. Drop it.

Makes sense, will do.

Thank you!
Arkadiusz

quoted

		parent_priv = dpll_pin_on_dpll_priv(dpll_ref->dpll, ppin);
		ret = ops->state_on_pin_get(pin,
					    dpll_pin_on_pin_priv(ppin, pin),
--
2.38.1