[PATCH 05/11] firmware: arm_scmi: stop reading past PINCTRL_LIST_ASSOCIATIONS replies

[Clément Le Goffic]

The transport cuts a reply larger than the receive buffer, but the iterator
still reads every identifier the reply announces. Use only the identifiers
that were copied and ask again for the others.

Fixes: 2145af01b9cb ("firmware: arm_scmi: Add basic support for SCMI v3.2 pincontrol protocol")
Signed-off-by: Clément Le Goffic <clegoffic at baylibre.com>
---
 drivers/firmware/arm_scmi/pinctrl.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/firmware/arm_scmi/pinctrl.c b/drivers/firmware/arm_scmi/pinctrl.c
index 42cb1aef1fe1..69645ce73d9d 100644
--- a/drivers/firmware/arm_scmi/pinctrl.c
+++ b/drivers/firmware/arm_scmi/pinctrl.c
@@ -261,10 +261,22 @@ static int iter_pinctrl_assoc_update_state(struct scmi_iterator_state *st,
 					   const void *response, void *priv)
 {
 	const struct scmi_resp_pinctrl_list_assoc *r = response;
+	unsigned int nr_fit = 0;
 
 	st->num_returned = RETURNED(r->flags);
 	st->num_remaining = REMAINING(r->flags);
 
+	if (st->rx_len > sizeof(*r))
+		nr_fit = (st->rx_len - sizeof(*r)) / sizeof(r->array[0]);
+
+	if (st->num_returned > nr_fit) {
+		if (!nr_fit)
+			return -EPROTO;
+
+		st->num_remaining += st->num_returned - nr_fit;
+		st->num_returned = nr_fit;
+	}
+
 	return 0;
 }
 

-- 
2.56.0