From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BF0FE1865 for ; Mon, 11 Apr 2022 17:50:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1649699435; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=jZr8+/3dMtuPdhdci07RfqKq5wNhW11aZAga7dGt9wM=; b=SinAb22+n1HVyapcDvDkQ3kmsJBMyM6z3LAQt6zS8MC4nXCOfRX/5I9cNLgj7j3oKUUOFb U85pq2zGMBuHCC00Gyfsz+WIlxI/iJ1h2O4olbeicTfZL7h9/ULKq8cfDKURzxg1IOiMwc JKSIzkpb7+unfjyvusNV9U0bHDmhR68= Received: from mail-qt1-f197.google.com (mail-qt1-f197.google.com [209.85.160.197]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-85-eiOkd7GcOUKbPuRPVmZyfQ-1; Mon, 11 Apr 2022 13:50:34 -0400 X-MC-Unique: eiOkd7GcOUKbPuRPVmZyfQ-1 Received: by mail-qt1-f197.google.com with SMTP id g22-20020ac870d6000000b002e20a1508ecso13172609qtp.19 for ; Mon, 11 Apr 2022 10:50:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=jZr8+/3dMtuPdhdci07RfqKq5wNhW11aZAga7dGt9wM=; b=Qu33DwzviSd8nqv/oavgKAPauaTcyu4uNfEF0mZQCczl75UJFCrnkHxeMwjJ4NykNd blgzmnVL8r4SYcNMUWWJFzt8I+nDIS7OBsJ5FdDGN/6aw6W/lXbjljyqsCww/21NdFTa WoSwIgbH1N5o6zYHLWl4Y4GD5/4sAClUnYFA0lAC2rQ3XsrCfy5GL1Tt0okJfXSGAGPd STPvNamx5hrqnOUIgxgjueKX9q0JhJMAtOJOKDwX3x5P5XbF+XahJJqooU66hnhFQ1zU H7KCt18nFA9NpsBmehgoQuG6FUtjgMG9UjmcKIq8LPrsbwU9HMNFUxlIRGvMyNvgF66t FqvQ== X-Gm-Message-State: AOAM530e6CzYklKBOdYOn0sIOgx+5mLV7GvujRnT0JprsY/ogtNPPWjw Fu6kPpzIXAoaGGiDUQmR6tkfmeKGNnoS0gv4BApe5DCpp3ugEv1LYvRAopPGXKWVOKdiAgNmKFi DS4aa8IeK2w51ag== X-Received: by 2002:a05:620a:2944:b0:67e:c9bf:3f9b with SMTP id n4-20020a05620a294400b0067ec9bf3f9bmr421907qkp.144.1649699434292; Mon, 11 Apr 2022 10:50:34 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzia1Yr5YPgHPUPuyWMsagB0zFBS5Py6/T1HccII27aP7kxWSF8b6jjxJdrdf6VFG6mwt4eeg== X-Received: by 2002:a05:620a:2944:b0:67e:c9bf:3f9b with SMTP id n4-20020a05620a294400b0067ec9bf3f9bmr421892qkp.144.1649699434061; Mon, 11 Apr 2022 10:50:34 -0700 (PDT) Received: from dell-per740-01.7a2m.lab.eng.bos.redhat.com (nat-pool-bos-t.redhat.com. [66.187.233.206]) by smtp.gmail.com with ESMTPSA id a24-20020a05620a067800b0069c233fa524sm1987715qkh.1.2022.04.11.10.50.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Apr 2022 10:50:33 -0700 (PDT) From: Tom Rix To: tim@cyberelk.net, axboe@kernel.dk, nathan@kernel.org, ndesaulniers@google.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Tom Rix Subject: [PATCH v2] pcd: do not leak information in ioctl Date: Mon, 11 Apr 2022 13:50:26 -0400 Message-Id: <20220411175026.2961880-1-trix@redhat.com> X-Mailer: git-send-email 2.27.0 Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=trix@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII"; x-default=true clang static analysis reports this representative issue pcd.c:832:22: warning: Assigned value is garbage or undefined tochdr->cdth_trk0 = buffer[2]; ^ ~~~~~~~~~ If the call to pcd_atapi fails, buffer is an unknown state. Passing an unknown buffer back to the user can leak information and is a security risk. Check before returning this buffer to the user. The per-case variables cmd and buffer are common. Change their scope to function level. Change colliding parameter name cmd to request. Cleanup whitespace Additionally initialize the buffer to zero. This problem can be seen in the 2.4.0 kernel However this scm only goes back as far as 2.6.12 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Tom Rix --- v2: split from combined scsi,pcd patch drivers/block/paride/pcd.c | 87 +++++++++++++++++--------------------- 1 file changed, 38 insertions(+), 49 deletions(-) diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c index f462ad67931a..2315918e3647 100644 --- a/drivers/block/paride/pcd.c +++ b/drivers/block/paride/pcd.c @@ -810,67 +810,56 @@ static void do_pcd_read_drq(void) /* the audio_ioctl stuff is adapted from sr_ioctl.c */ -static int pcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, void *arg) +static int pcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int request, void *arg) { struct pcd_unit *cd = cdi->handle; + char cmd[12] = { GPCMD_READ_TOC_PMA_ATIP, 0, 0, 0, 0, 0, 0, 0, 12, 0, 0, 0 }; + char buffer[32] = {}; - switch (cmd) { - + switch (request) { case CDROMREADTOCHDR: + { + struct cdrom_tochdr *tochdr = + (struct cdrom_tochdr *) arg; - { - char cmd[12] = - { GPCMD_READ_TOC_PMA_ATIP, 0, 0, 0, 0, 0, 0, 0, 12, - 0, 0, 0 }; - struct cdrom_tochdr *tochdr = - (struct cdrom_tochdr *) arg; - char buffer[32]; - int r; - - r = pcd_atapi(cd, cmd, 12, buffer, "read toc header"); + if (pcd_atapi(cd, cmd, 12, buffer, "read toc header")) + return -EIO; - tochdr->cdth_trk0 = buffer[2]; - tochdr->cdth_trk1 = buffer[3]; + tochdr->cdth_trk0 = buffer[2]; + tochdr->cdth_trk1 = buffer[3]; - return r ? -EIO : 0; - } + return 0; + } case CDROMREADTOCENTRY: - - { - char cmd[12] = - { GPCMD_READ_TOC_PMA_ATIP, 0, 0, 0, 0, 0, 0, 0, 12, - 0, 0, 0 }; - - struct cdrom_tocentry *tocentry = - (struct cdrom_tocentry *) arg; - unsigned char buffer[32]; - int r; - - cmd[1] = - (tocentry->cdte_format == CDROM_MSF ? 0x02 : 0); - cmd[6] = tocentry->cdte_track; - - r = pcd_atapi(cd, cmd, 12, buffer, "read toc entry"); - - tocentry->cdte_ctrl = buffer[5] & 0xf; - tocentry->cdte_adr = buffer[5] >> 4; - tocentry->cdte_datamode = - (tocentry->cdte_ctrl & 0x04) ? 1 : 0; - if (tocentry->cdte_format == CDROM_MSF) { - tocentry->cdte_addr.msf.minute = buffer[9]; - tocentry->cdte_addr.msf.second = buffer[10]; - tocentry->cdte_addr.msf.frame = buffer[11]; - } else - tocentry->cdte_addr.lba = - (((((buffer[8] << 8) + buffer[9]) << 8) - + buffer[10]) << 8) + buffer[11]; - - return r ? -EIO : 0; + { + struct cdrom_tocentry *tocentry = + (struct cdrom_tocentry *) arg; + + cmd[1] = (tocentry->cdte_format == CDROM_MSF ? 0x02 : 0); + cmd[6] = tocentry->cdte_track; + + if (pcd_atapi(cd, cmd, 12, buffer, "read toc entry")) + return -EIO; + + tocentry->cdte_ctrl = buffer[5] & 0xf; + tocentry->cdte_adr = buffer[5] >> 4; + tocentry->cdte_datamode = + (tocentry->cdte_ctrl & 0x04) ? 1 : 0; + if (tocentry->cdte_format == CDROM_MSF) { + tocentry->cdte_addr.msf.minute = buffer[9]; + tocentry->cdte_addr.msf.second = buffer[10]; + tocentry->cdte_addr.msf.frame = buffer[11]; + } else { + tocentry->cdte_addr.lba = + (((((buffer[8] << 8) + buffer[9]) << 8) + + buffer[10]) << 8) + buffer[11]; } - default: + return 0; + } + default: return -ENOSYS; } } -- 2.27.0