FAILED: patch "[PATCH] wifi: mt76: mt7996: bound the device EEPROM address before" failed to apply to 6.6-stable tree

FAILED: patch "[PATCH] wifi: mt76: mt7996: bound the device EEPROM address before" failed to apply to 6.6-stable tree

[gregkh]

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 13b3c29a782033ce4a230be9e5618032813dbcd4
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026090415-flame-radiance-eb73@gregkh' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 13b3c29a782033ce4a230be9e5618032813dbcd4 Mon Sep 17 00:00:00 2001
From: Bryam Vargas <hexlabsecurity@proton.me>
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 <hexlabsecurity@proton.me>
Link: https://patch.msgid.link/20260625-b4-disp-16f99062-v1-2-aee52ecf61b9@proton.me
Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
index 2e83f4b79c87..a1bae5db8500 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
@@ -4352,11 +4352,18 @@ 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:

[PATCH 6.6.y] wifi: mt76: mt7996: bound the device EEPROM address before the EFUSE copy

[Sasha Levin]

From: Bryam Vargas <hexlabsecurity@proton.me>

[ Upstream commit 13b3c29a782033ce4a230be9e5618032813dbcd4 ]

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 <hexlabsecurity@proton.me>
Link: https://patch.msgid.link/20260625-b4-disp-16f99062-v1-2-aee52ecf61b9@proton.me
Signed-off-by: Felix Fietkau <nbd@nbd.name>
[ adapted mt7996_mcu_get_eeprom() changes to the older fixed 16-byte EFUSE implementation. ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/wireless/mediatek/mt76/mt7996/mcu.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
index 2abc8d15ea852..7c079de63c51d 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
@@ -3107,7 +3107,13 @@ int mt7996_mcu_get_eeprom(struct mt7996_dev *dev, u32 offset)
 	valid = le32_to_cpu(*(__le32 *)(skb->data + 16));
 	if (valid) {
 		u32 addr = le32_to_cpu(*(__le32 *)(skb->data + 12));
-		u8 *buf = (u8 *)dev->mt76.eeprom.data + addr;
+		u8 *buf;
+
+		if (addr > dev->mt76.eeprom.size - MT7996_EEPROM_BLOCK_SIZE) {
+			dev_kfree_skb(skb);
+			return -EINVAL;
+		}
+		buf = (u8 *)dev->mt76.eeprom.data + addr;
 
 		skb_pull(skb, 48);
 		memcpy(buf, skb->data, MT7996_EEPROM_BLOCK_SIZE);
-- 
2.53.0