[PATCH 6.1.y 2/2] octeontx2-af: CGX: add bounds check to cgx_speed_mbps index

[Sasha Levin <sashal@kernel.org>]

From: Sam Daly <sam@samdaly.ie>

[ Upstream commit c0bf0a4f3f1f5f57aa83e1400ba4f56f0abfd542 ]

cgx_speed_mbps has 13 elements but RESP_LINKSTAT_SPEED can yield values
0-15. If it returns a value >= 13, this causes an out-of-bounds array
access. Add a bounds check and default to speed 0 if the index is out of
range.

Fixes: 61071a871ea6 ("octeontx2-af: Forward CGX link notifications to PFs")
Cc: Sunil Goutham <sgoutham@marvell.com>
Cc: Linu Cherian <lcherian@marvell.com>
Cc: Geetha sowjanya <gakula@marvell.com>
Cc: hariprasad <hkelam@marvell.com>
Cc: Subbaraya Sundeep <sbhatta@marvell.com>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>
Cc: stable <stable@kernel.org>
Signed-off-by: Sam Daly <sam@samdaly.ie>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/2026051352-refined-demise-e88d@gregkh
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/marvell/octeontx2/af/cgx.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/cgx.c b/drivers/net/ethernet/marvell/octeontx2/af/cgx.c
index 0d8954f934b42..d28dfe11227b9 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/cgx.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/cgx.c
@@ -1228,13 +1228,18 @@ static inline void link_status_user_format(u64 lstat,
 					   struct cgx_link_user_info *linfo,
 					   struct cgx *cgx, u8 lmac_id)
 {
+	unsigned int speed;
+
 	linfo->link_up = FIELD_GET(RESP_LINKSTAT_UP, lstat);
 	linfo->full_duplex = FIELD_GET(RESP_LINKSTAT_FDUPLEX, lstat);
-	linfo->speed = cgx_speed_mbps[FIELD_GET(RESP_LINKSTAT_SPEED, lstat)];
 	linfo->an = FIELD_GET(RESP_LINKSTAT_AN, lstat);
 	linfo->fec = FIELD_GET(RESP_LINKSTAT_FEC, lstat);
 	linfo->lmac_type_id = cgx_get_lmac_type(cgx, lmac_id);
 
+	speed = FIELD_GET(RESP_LINKSTAT_SPEED, lstat);
+	linfo->speed = speed < ARRAY_SIZE(cgx_speed_mbps) ?
+		       cgx_speed_mbps[speed] : 0;
+
 	if (linfo->lmac_type_id >= LMAC_MODE_MAX) {
 		dev_err(&cgx->pdev->dev, "Unknown lmac_type_id %d reported by firmware on cgx port%d:%d",
 			linfo->lmac_type_id, cgx->cgx_id, lmac_id);
-- 
2.53.0