4.18-stable review patch. If anyone has any objections, please let me know.
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From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit ae636fb1554833ee5133ca47bf4b2791b6739c52 ]
This is a static checker fix, not something I have tested. The issue is that on the second iteration through the loop, we jump forward by le32_to_cpu(auth_req->length) bytes. The problem is that if the length is more than "buflen" then we end up with a negative "buflen". A negative buflen is type promoted to a high positive value and the loop continues but it's accessing beyond the end of the buffer.
I believe the "auth_req->length" comes from the firmware and if the firmware is malicious or buggy, you're already toasted so the impact of this bug is probably not very severe.
Fixes: 030645aceb3d ("rndis_wlan: handle 802.11 indications from device") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Kalle Valo kvalo@codeaurora.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/wireless/rndis_wlan.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/net/wireless/rndis_wlan.c +++ b/drivers/net/wireless/rndis_wlan.c @@ -2928,6 +2928,8 @@ static void rndis_wlan_auth_indication(s
while (buflen >= sizeof(*auth_req)) { auth_req = (void *)buf; + if (buflen < le32_to_cpu(auth_req->length)) + return; type = "unknown"; flags = le32_to_cpu(auth_req->flags); pairwise_error = false;