[PATCH 5.12 489/700] net: phy: mscc: fix macsec key length

[Greg Kroah-Hartman]

From: Antoine Tenart <atenart@xxxxxxxxxx>

[ Upstream commit c309217f91f2d2097c2a0a832d9bff50b88c81dc ]

The key length used to store the macsec key was set to MACSEC_KEYID_LEN
(16), which is an issue as:
- This was never meant to be the key length.
- The key length can be > 16.

Fix this by using MACSEC_MAX_KEY_LEN instead (the max length accepted in
uAPI).

Fixes: 28c5107aa904 ("net: phy: mscc: macsec support")
Reported-by: Lior Nahmanson <liorna@xxxxxxxxxx>
Signed-off-by: Antoine Tenart <atenart@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/phy/mscc/mscc_macsec.c | 2 +-
 drivers/net/phy/mscc/mscc_macsec.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/mscc/mscc_macsec.c b/drivers/net/phy/mscc/mscc_macsec.c
index 10be266e48e8..b7b2521c73fb 100644
--- a/drivers/net/phy/mscc/mscc_macsec.c
+++ b/drivers/net/phy/mscc/mscc_macsec.c
@@ -501,7 +501,7 @@ static u32 vsc8584_macsec_flow_context_id(struct macsec_flow *flow)
 }
 
 /* Derive the AES key to get a key for the hash autentication */
-static int vsc8584_macsec_derive_key(const u8 key[MACSEC_KEYID_LEN],
+static int vsc8584_macsec_derive_key(const u8 key[MACSEC_MAX_KEY_LEN],
 				     u16 key_len, u8 hkey[16])
 {
 	const u8 input[AES_BLOCK_SIZE] = {0};
diff --git a/drivers/net/phy/mscc/mscc_macsec.h b/drivers/net/phy/mscc/mscc_macsec.h
index 9c6d25e36de2..453304bae778 100644
--- a/drivers/net/phy/mscc/mscc_macsec.h
+++ b/drivers/net/phy/mscc/mscc_macsec.h
@@ -81,7 +81,7 @@ struct macsec_flow {
 	/* Highest takes precedence [0..15] */
 	u8 priority;
 
-	u8 key[MACSEC_KEYID_LEN];
+	u8 key[MACSEC_MAX_KEY_LEN];
 
 	union {
 		struct macsec_rx_sa *rx_sa;
-- 
2.30.2