From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D7E07C433C1 for ; Sat, 27 Mar 2021 21:45:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9883161966 for ; Sat, 27 Mar 2021 21:45:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231249AbhC0VpY (ORCPT ); Sat, 27 Mar 2021 17:45:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57130 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231243AbhC0Vo6 (ORCPT ); Sat, 27 Mar 2021 17:44:58 -0400 Received: from mail-lf1-x134.google.com (mail-lf1-x134.google.com [IPv6:2a00:1450:4864:20::134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66831C0613B1 for ; Sat, 27 Mar 2021 14:44:58 -0700 (PDT) Received: by mail-lf1-x134.google.com with SMTP id o10so12835714lfb.9 for ; Sat, 27 Mar 2021 14:44:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=i3wg0RfDT7B12umkmZco55Pf5265Dscr2E2y7rSMHH4=; b=HZvJe+CdUE992BE0QCOrxokIQdt6paoBnnPGBEe0DrTB7tXBPJNPf/GgvJZ5Z5bBCd /RhnjCEYipC0dJlI06wBFMdXQchowkPZQcCcZxRtOGlXNryfqpJygascdEY/gMw07Heq rNTwGTEOZGK2Grptz2/ul0QcIW04y4NmCL8ahcI78drcEvQDyFuBX3/gkICircHctTW0 OQnBgjW65GOqpIs6uk/6WUd5CHg7u+pis2u79QnZRokAOTAHyY8/8nFDL8tMs2SkNe/5 E4BcT/rriWsYAKHb63LnuOqOWMCwSzcw43WgOfY2FmU7uTDIyzsxhCjyCrQhLxt5J1XW n/Wg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=i3wg0RfDT7B12umkmZco55Pf5265Dscr2E2y7rSMHH4=; b=piplLEK/KjQOmp/+FuPFxfzouOOKNkV0bTeysw9ZGYX7Jelmtg3YuZeXCAgUDzYQhS m97lzNxC17nEjBbkk/uAUMaGQbelXlqfGItEJ79/IqvRqCCyX0875KXnKC8NdM+DtnFh wrTLCdyoilOPAzLxn8wWIyinYWrCILSCXw59xgf7pDbLc4sZhqXKKunMcd7GHTEOwFPb VQsUbNnF1W6yXeRFiQf8j/XU3O5XUm+7oafJdqBK98LuKQQTFv24kBfUv+zFlTciUcsB yYiLwjNvIZpWn2lYCpf5P2pju5vUJ68ewYVn9jEzASWIJ+DeGqL0h5s5Z661gB9PFg91 xgQw== X-Gm-Message-State: AOAM533ZSEewadzu07vWK5Wj8ibip8QRQroVL8w1au4c7ZM/57KFMhuo 4rfL5IDoxiA1Zz4KpLqZAjo= X-Google-Smtp-Source: ABdhPJwct+lVW+QjDdIY0f7p8L5CVWELm18ELwK3pnHu7XC1GiJwcdpR95BAFAXKj6wG3hbg1284Tw== X-Received: by 2002:a19:ec1a:: with SMTP id b26mr11614441lfa.610.1616881496726; Sat, 27 Mar 2021 14:44:56 -0700 (PDT) Received: from localhost.localdomain ([94.103.227.42]) by smtp.gmail.com with ESMTPSA id l29sm1303347lfp.63.2021.03.27.14.44.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 27 Mar 2021 14:44:56 -0700 (PDT) From: Pavel Skripkin To: gregkh@linuxfoundation.org, jirislaby@kernel.org Cc: linux-kernel@vger.kernel.org, Pavel Skripkin , syzbot+bcc922b19ccc64240b42@syzkaller.appspotmail.com Subject: [PATCH] tty: fix memory leak in vc_deallocate Date: Sun, 28 Mar 2021 00:44:43 +0300 Message-Id: <20210327214443.21548-1-paskripkin@gmail.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org syzbot reported memory leak in tty/vt. The problem was in VT_DISALLOCATE ioctl cmd. After allocating unimap with PIO_UNIMAP it wasn't freed via VT_DISALLOCATE, but vc_cons[currcons].d was zeroed. Signed-off-by: Pavel Skripkin Reported-by: syzbot+bcc922b19ccc64240b42@syzkaller.appspotmail.com --- drivers/tty/vt/vt.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 284b07224c55..0cc360da5426 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -1381,6 +1381,7 @@ struct vc_data *vc_deallocate(unsigned int currcons) atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, ¶m); vcs_remove_sysfs(currcons); visual_deinit(vc); + con_free_unimap(vc); put_pid(vc->vt_pid); vc_uniscr_set(vc, NULL); kfree(vc->vc_screenbuf); -- 2.30.2