From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx4+LW4lzhI2/lHBRd+nZdIvXW+Po7s3a2wQtQduG1I1TEOQljZG85dIeQJcLFsJDdR04cHi+ ARC-Seal: i=1; a=rsa-sha256; t=1523472102; cv=none; d=google.com; s=arc-20160816; b=yl9PvbnJF7VPoqBOxuKKkkq489qxbJ3hPxPECExe+RTxbZ7p2F63ci8mjyr4VwAjQe 358id2YSKUyWWBLcKvzZ/6ATZmBrYiHE+7zqviKOGdHGSROh9jtQ0+91TSHmRQ7WH6Ch EHkMklp3DMdYsoyU9ofI31cQTWS0uVdWwMDzyLfiYmCUm0EQB26ZZNvv09wfFXffdTc/ oqp5AoIeVJSKJA5PuCaTmyoqufHnajcM5cFUWJGcWpqHymUqI+s8FD4YbGAuuRQeySny AyimM++9RouraOykdCqq+MYsMVh8dOgi1ZkTQEuA22sR6A8e/UOyneiP/mUqxl9+Vo5N 5CpQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=NWnVLGAMhEACUVK5aw0zyLeIik1WiAb+9rHdDrKMSv8=; b=moCvRu7imY9uqIxfoV9MiW9psXMnfnmRQYnzCW0Xt6rkbanJqrm4pQIF2GBlUg6soG KVG2h7dbF2MkjM7yK1zQic16RAgkas3WOANUIxyVbljAhYpGt93yXasWnr+NRrqihKIa B0xWHhZmrdzPesr++1SXelS7LiovNeQFbDn0En3r/aOlt7aC4JjQSReFytdtoVKETaV0 YrpY3GIaEvQXymXtmOI21Hpv/ScwaZ819fDCjkm9qfh4lepyTtce0jsBCf42qE6gFct6 NEBYLl7hArGjyb8pn/FFpakTx0WBEM177viQFMCTrLAddE/6rBwIz8J/AUAQLwHlb007 ipCQ== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrey Konovalov , Firo Yang , "David S. Miller" , Sasha Levin Subject: [PATCH 3.18 053/121] hdlcdrv: Fix divide by zero in hdlcdrv_ioctl Date: Wed, 11 Apr 2018 20:35:56 +0200 Message-Id: <20180411183459.539382641@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180411183456.195010921@linuxfoundation.org> References: <20180411183456.195010921@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1597476282817788876?= X-GMAIL-MSGID: =?utf-8?q?1597476282817788876?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Firo Yang [ Upstream commit fb3ce90b7d7761b6f7f28f0ff5c456ef6b5229a1 ] syszkaller fuzzer triggered a divide by zero, when set calibration through ioctl(). To fix it, test 'bitrate' if it is negative or 0, just return -EINVAL. Reported-by: Andrey Konovalov Signed-off-by: Firo Yang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/hamradio/hdlcdrv.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/hamradio/hdlcdrv.c +++ b/drivers/net/hamradio/hdlcdrv.c @@ -571,6 +571,8 @@ static int hdlcdrv_ioctl(struct net_devi case HDLCDRVCTL_CALIBRATE: if(!capable(CAP_SYS_RAWIO)) return -EPERM; + if (s->par.bitrate <= 0) + return -EINVAL; if (bi.data.calibrate > INT_MAX / s->par.bitrate) return -EINVAL; s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;