netdev - [PATCH AUTOSEL 5.10 05/18] wifi: airo: do not assign -1 to unsigned char

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20221119021459.1775052-5-sashal@kernel.org>
Date:   Fri, 18 Nov 2022 21:14:46 -0500
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     "Jason A. Donenfeld" <Jason@...c4.com>,
        Kalle Valo <kvalo@...nel.org>, linux-wireless@...r.kernel.org,
        Sasha Levin <sashal@...nel.org>, davem@...emloft.net,
        edumazet@...gle.com, kuba@...nel.org, pabeni@...hat.com,
        songmuchun@...edance.com, Julia.Lawall@...ia.fr,
        akpm@...ux-foundation.org, netdev@...r.kernel.org
Subject: [PATCH AUTOSEL 5.10 05/18] wifi: airo: do not assign -1 to unsigned char

From: "Jason A. Donenfeld" <Jason@...c4.com>

[ Upstream commit e6cb8769452e8236b52134e5cb4a18b8f5986932 ]

With char becoming unsigned by default, and with `char` alone being
ambiguous and based on architecture, we get a warning when assigning the
unchecked output of hex_to_bin() to that unsigned char. Mark `key` as a
`u8`, which matches the struct's type, and then check each call to
hex_to_bin() before casting.

Cc: Kalle Valo <kvalo@...nel.org>
Cc: linux-wireless@...r.kernel.org
Signed-off-by: Jason A. Donenfeld <Jason@...c4.com>
Signed-off-by: Kalle Valo <kvalo@...nel.org>
Link: https://lore.kernel.org/r/20221024162843.535921-1-Jason@zx2c4.com
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/net/wireless/cisco/airo.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/cisco/airo.c b/drivers/net/wireless/cisco/airo.c
index 0569f37e9ed5..8c9c6bfbaeee 100644
--- a/drivers/net/wireless/cisco/airo.c
+++ b/drivers/net/wireless/cisco/airo.c
@@ -5236,7 +5236,7 @@ static int get_wep_tx_idx(struct airo_info *ai)
 	return -1;
 }
 
-static int set_wep_key(struct airo_info *ai, u16 index, const char *key,
+static int set_wep_key(struct airo_info *ai, u16 index, const u8 *key,
 		       u16 keylen, int perm, int lock)
 {
 	static const unsigned char macaddr[ETH_ALEN] = { 0x01, 0, 0, 0, 0, 0 };
@@ -5287,7 +5287,7 @@ static void proc_wepkey_on_close(struct inode *inode, struct file *file)
 	struct net_device *dev = PDE_DATA(inode);
 	struct airo_info *ai = dev->ml_priv;
 	int i, rc;
-	char key[16];
+	u8 key[16];
 	u16 index = 0;
 	int j = 0;
 
@@ -5315,12 +5315,22 @@ static void proc_wepkey_on_close(struct inode *inode, struct file *file)
 	}
 
 	for (i = 0; i < 16*3 && data->wbuffer[i+j]; i++) {
+		int val;
+
+		if (i % 3 == 2)
+			continue;
+
+		val = hex_to_bin(data->wbuffer[i+j]);
+		if (val < 0) {
+			airo_print_err(ai->dev->name, "WebKey passed invalid key hex");
+			return;
+		}
 		switch(i%3) {
 		case 0:
-			key[i/3] = hex_to_bin(data->wbuffer[i+j])<<4;
+			key[i/3] = (u8)val << 4;
 			break;
 		case 1:
-			key[i/3] |= hex_to_bin(data->wbuffer[i+j]);
+			key[i/3] |= (u8)val;
 			break;
 		}
 	}
-- 
2.35.1