From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Wed, 19 Feb 2025 17:51:42 +0100 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1tknIV-004Ntn-0v for lore@lore.pengutronix.de; Wed, 19 Feb 2025 17:51:42 +0100 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1tknIU-0006F8-4Q for lore@pengutronix.de; Wed, 19 Feb 2025 17:51:42 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Cg5WXS1ieXe4FjsV+Z+qn2sC5y8wwB7W6Mz7lP4k05E=; b=Yl1P1urJMqRhj2Ds2Q5WZx/p0E kxhZXU7mhZ5vMfXe2l/FJd1CN4dCNPQpkImKckS3B55GG4gHePQGmxE2RWCr3eDqA7ZVyjH3Ff+TG y1BCDcR9L7gnBwgischSshQKc/MEqNqgy7weeSarnmsh2o9+c11JL9S6F9ufe8PJf89eTbBblqw7F N1EJ4r10/v2NOwB30ivGNpI42o1Y2nTp45oUUwd4A+q/XVkcrq5pDXieDgpv/pSsQGRDtEFdk2SHv uCVruYMRUkVmnDULt4nVCfocvNdgR0Sxwy7YdnNfP8uNSM9LEQEyrOwL7+HW4P2ce7slRxLfKpf22 mMVSwpfw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tknI6-0000000DwP9-2sOi; Wed, 19 Feb 2025 16:51:18 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tknI4-0000000DwOA-1DBi for barebox@lists.infradead.org; Wed, 19 Feb 2025 16:51:17 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1tknI3-00066k-3S; Wed, 19 Feb 2025 17:51:15 +0100 Message-ID: <4d1d9746-0f83-4c4b-b239-8001939b6d46@pengutronix.de> Date: Wed, 19 Feb 2025 17:51:14 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Sascha Hauer , Barebox List Cc: Jonathan Bar Or References: <20250219141844.1912413-1-s.hauer@pengutronix.de> <20250219141844.1912413-4-s.hauer@pengutronix.de> Content-Language: en-US From: Ahmad Fatoum In-Reply-To: <20250219141844.1912413-4-s.hauer@pengutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250219_085116_329287_152EA7B9 X-CRM114-Status: GOOD ( 18.34 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-5.3 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 3/5] CVE-2025-26723: fs: ext4: fix malloc(size + constant) buffer overflow issues X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) On 19.02.25 15:18, Sascha Hauer wrote: > The pattern malloc(size + constant) is dangerous when size can be > manipulated by an attacker. In that case 'size' can be manipulated > in a way that 'size + constant' is 0 due to integer overflow. The > result is a zero sized buffer to which is then data written to. > > Avoid this by using size_add() instead. > > Reported-by: Jonathan Bar Or > Signed-off-by: Sascha Hauer Reviewed-by: Ahmad Fatoum > --- > fs/ext4/ext_barebox.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/ext4/ext_barebox.c b/fs/ext4/ext_barebox.c > index 163c4d2fe1..7480c045d7 100644 > --- a/fs/ext4/ext_barebox.c > +++ b/fs/ext4/ext_barebox.c > @@ -189,7 +189,7 @@ static const char *ext_get_link(struct dentry *dentry, struct inode *inode) > > BUG_ON(inode->i_link); > > - inode->i_link = zalloc(inode->i_size + 1); > + inode->i_link = zalloc(size_add(inode->i_size, 1)); > > ret = ext4fs_read_file(node, 0, inode->i_size, inode->i_link); > if (ret == 0) { -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |