netdev - [PATCH v2 2/3] ath6kl: fix division by zero in send path

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 for Android: free password hash cracker in your pocket

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

Message-Id: <20211027080819.6675-3-johan@kernel.org>
Date:   Wed, 27 Oct 2021 10:08:18 +0200
From:   Johan Hovold <johan@...nel.org>
To:     Kalle Valo <kvalo@...eaurora.org>
Cc:     Amitkumar Karwar <amitkarwar@...il.com>,
        Ganapathi Bhat <ganapathi017@...il.com>,
        Sharvari Harisangam <sharvari.harisangam@....com>,
        Xinming Hu <huxinming820@...il.com>,
        Brian Norris <briannorris@...omium.org>,
        linux-wireless@...r.kernel.org, netdev@...r.kernel.org,
        linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org,
        Johan Hovold <johan@...nel.org>, stable@...r.kernel.org
Subject: [PATCH v2 2/3] ath6kl: fix division by zero in send path

Add the missing endpoint max-packet sanity check to probe() to avoid
division by zero in ath10k_usb_hif_tx_sg() in case a malicious device
has broken descriptors (or when doing descriptor fuzz testing).

Note that USB core will reject URBs submitted for endpoints with zero
wMaxPacketSize but that drivers doing packet-size calculations still
need to handle this (cf. commit 2548288b4fb0 ("USB: Fix: Don't skip
endpoint descriptors with maxpacket=0")).

Fixes: 9cbee358687e ("ath6kl: add full USB support")
Cc: stable@...r.kernel.org      # 3.5
Signed-off-by: Johan Hovold <johan@...nel.org>
---
 drivers/net/wireless/ath/ath6kl/usb.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/wireless/ath/ath6kl/usb.c b/drivers/net/wireless/ath/ath6kl/usb.c
index bd367b79a4d3..aba70f35e574 100644
--- a/drivers/net/wireless/ath/ath6kl/usb.c
+++ b/drivers/net/wireless/ath/ath6kl/usb.c
@@ -340,6 +340,11 @@ static int ath6kl_usb_setup_pipe_resources(struct ath6kl_usb *ar_usb)
 				   le16_to_cpu(endpoint->wMaxPacketSize),
 				   endpoint->bInterval);
 		}
+
+		/* Ignore broken descriptors. */
+		if (usb_endpoint_maxp(endpoint) == 0)
+			continue;
+
 		urbcount = 0;
 
 		pipe_num =
-- 
2.32.0