From 76c38706bbab7748dfea45545b58ee8f39be10cd Mon Sep 17 00:00:00 2001 From: Bryam Vargas Date: Thu, 25 Jun 2026 07:10:27 -0500 Subject: [PATCH] wifi: mt76: mt7996: bound the device EEPROM address before the EFUSE copy mt7996_mcu_get_eeprom() derives the destination of the EFUSE/EXT block copy from the address reported by the MCU response (event->addr, a device-controlled __le32) and clamps only the copy length, never the destination offset into dev->mt76.eeprom.data. A malicious or malfunctioning device can report an arbitrary address and drive an out-of-bounds write of up to MT7996_EXT_EEPROM_BLOCK_SIZE bytes past eeprom.data. Reject a response whose address would place the copy outside eeprom.data before deriving the destination pointer. Devices that echo the requested in-bounds offset are unaffected. Fixes: 98686cd21624 ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi 7 (802.11be) devices") Cc: stable@vger.kernel.org Signed-off-by: Bryam Vargas Link: https://patch.msgid.link/20260625-b4-disp-16f99062-v1-2-aee52ecf61b9@proton.me Signed-off-by: Felix Fietkau --- mt7996/mcu.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mt7996/mcu.c b/mt7996/mcu.c index 1bd32c00..c4a46007 100644 --- a/mt7996/mcu.c +++ b/mt7996/mcu.c @@ -4575,11 +4575,18 @@ int mt7996_mcu_get_eeprom(struct mt7996_dev *dev, u32 offset, u8 *buf, u32 buf_l event = (struct mt7996_mcu_eeprom_access_event *)skb->data; if (event->valid) { u32 ret_len = le32_to_cpu(event->eeprom.ext_eeprom.data_len); + u32 block = mode == EEPROM_MODE_EXT ? MT7996_EXT_EEPROM_BLOCK_SIZE : + MT7996_EEPROM_BLOCK_SIZE; addr = le32_to_cpu(event->addr); - if (!buf) + if (!buf) { + if (addr > dev->mt76.eeprom.size - block) { + dev_kfree_skb(skb); + return -EINVAL; + } buf = (u8 *)dev->mt76.eeprom.data + addr; + } switch (mode) { case EEPROM_MODE_EFUSE: