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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1CF2C433F5 for ; Wed, 15 Dec 2021 11:16:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234523AbhLOLQZ (ORCPT ); Wed, 15 Dec 2021 06:16:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34134 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236990AbhLOLQT (ORCPT ); Wed, 15 Dec 2021 06:16:19 -0500 Received: from mail-pg1-x534.google.com (mail-pg1-x534.google.com [IPv6:2607:f8b0:4864:20::534]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 521CBC06173F for ; Wed, 15 Dec 2021 03:16:19 -0800 (PST) Received: by mail-pg1-x534.google.com with SMTP id 200so11070534pgg.3 for ; Wed, 15 Dec 2021 03:16:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1J5rh8c88OIRT0cbzlqagWTRc0k7QBWGbd0OGAGYHKQ=; b=ZRiIx3G1K5spEnSmaztOgrLBgOSqAYBIV6SNAJZT37P61/XxH96oEMNKKATV+UNP06 Q1W+R6yOxGXce8GaRa/tLBrvpq2dnguaNSXZD9ArtX9ASjoDWWgW/z4BSfbu29dNNyWa eyLisk9FIgXJP6YgPMkTtDIzBY3WgRs3B2fe1bbDMM/dB95MiBOaR3mOgrkga3+nnOaX vFuaY3J/kZZ3aV6ZR9jGHW55qE2KBOC79MXoVqTOXtBZn3c4w/+4W4A+/wz9sW/LyWbC mpnmQaG0lgV7726LjsbgvdfNWnqrDZFac70S/oN7Le6+RP8k5M552kDyrPPKsX9Lzutt A+JQ== 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=1J5rh8c88OIRT0cbzlqagWTRc0k7QBWGbd0OGAGYHKQ=; b=EXRyh8Bw4r8XYl0jkLXLXV0jfTucSc2WO0lWC30FiM5nDVLRoyhBr6/hUlU+lnc0FM siAApIOwaYGuVWOQcVpgb3UXo60A1blXNSV32WBgVHT1cDA/uJOEJAMchjm9IZCrwwHH U0SXE70fUcc7BsQmEYwyTZKmNT/BxITRLWshznnPJFA/yUXAC8/OkJnQo6tjra7Ge5+4 VQJgkAv91Y9Zhwn38VOpjwLYnvbUUUigT1Lerg4KD4lrZwj9tfTBtQQHgiCuzNRp9gjz VF/yPtGN/zWQhSbLOE9fgbuJCtuvEtpNDRBhQu3rGb1y1nGYO+qWHMLlOg7qlKyS7RxY zc/w== X-Gm-Message-State: AOAM532y9oPlyfT6iUUdUWIKy+hJddhskITbpHNPomqJDYgTkpUEm0ky BevPwxWvhq+jbS4xblUefNI= X-Google-Smtp-Source: ABdhPJyc5D+19GIGvcIvjihecYJUsuIx04Moljqr171eleFa0vxNImbOBsqZOGH6BQBVQlwm9rJWaw== X-Received: by 2002:a63:74b:: with SMTP id 72mr7584104pgh.231.1639566978876; Wed, 15 Dec 2021 03:16:18 -0800 (PST) Received: from ELIJAHBAI-MB0.tencent.com ([103.7.29.31]) by smtp.gmail.com with ESMTPSA id oa2sm5266812pjb.53.2021.12.15.03.16.16 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 15 Dec 2021 03:16:18 -0800 (PST) From: Haimin Zhang To: Greg KH , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Jakub Kicinski Cc: Haimin Zhang , security , elijahbai , netdev@vger.kernel.org Subject: [PATCH v4] netdevsim: Zero-initialize memory for new map's value in function nsim_bpf_map_alloc Date: Wed, 15 Dec 2021 19:15:30 +0800 Message-Id: <20211215111530.72103-1-tcs.kernel@gmail.com> X-Mailer: git-send-email 2.30.1 (Apple Git-130) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Zero-initialize memory for new map's value in function nsim_bpf_map_alloc since it may cause a potential kernel information leak issue, as follows: 1. nsim_bpf_map_alloc calls nsim_map_alloc_elem to allocate elements for a new map. 2. nsim_map_alloc_elem uses kmalloc to allocate map's value, but doesn't zero it. 3. A user application can use IOCTL BPF_MAP_LOOKUP_ELEM to get specific element's information in the map. 4. The kernel function map_lookup_elem will call bpf_map_copy_value to get the information allocated at step-2, then use copy_to_user to copy to the user buffer. This can only leak information for an array map. Fixes: 395cacb5f1a0 ("netdevsim: bpf: support fake map offload") Suggested-by: Jakub Kicinski Acked-by: Jakub Kicinski Signed-off-by: Haimin Zhang --- drivers/net/netdevsim/bpf.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c index 90aafb56f140..a43820212932 100644 --- a/drivers/net/netdevsim/bpf.c +++ b/drivers/net/netdevsim/bpf.c @@ -514,6 +514,7 @@ nsim_bpf_map_alloc(struct netdevsim *ns, struct bpf_offloaded_map *offmap) goto err_free; key = nmap->entry[i].key; *key = i; + memset(nmap->entry[i].value, 0, offmap->map.value_size); } } -- 2.30.1 (Apple Git-130)