From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 5D4F41C03 for ; Mon, 20 Mar 2023 15:03:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFAB8C433D2; Mon, 20 Mar 2023 15:03:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1679324588; bh=dPN4NDuHUJybMvzkSTkgEA0jocHVXO9EQNgBzNl2G9w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=juJJT9ypJjF5ksnxXDYlqZDIaB5boSGHJO+k3zYixIpUqaGIK+nYKGBuBnEsCZ7xH egn2fMjQr6i/fNsbE5/8ZDq/wAoyIaSkhkpC1ju+vV376eKhb1imPrWekv/xatvdNP VczEXEuNpq7cXaYjOa0YGU7Os6PzOPg6mRRrz0Z0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sven Schnelle , Vasily Gorbik Subject: [PATCH 5.4 57/60] s390/ipl: add missing intersection check to ipl_report handling Date: Mon, 20 Mar 2023 15:55:06 +0100 Message-Id: <20230320145433.293697903@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230320145430.861072439@linuxfoundation.org> References: <20230320145430.861072439@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Sven Schnelle commit a52e5cdbe8016d4e3e6322fd93d71afddb9a5af9 upstream. The code which handles the ipl report is searching for a free location in memory where it could copy the component and certificate entries to. It checks for intersection between the sections required for the kernel and the component/certificate data area, but fails to check whether the data structures linking these data areas together intersect. This might cause the iplreport copy code to overwrite the iplreport itself. Fix this by adding two addtional intersection checks. Cc: Fixes: 9641b8cc733f ("s390/ipl: read IPL report at early boot") Signed-off-by: Sven Schnelle Reviewed-by: Vasily Gorbik Signed-off-by: Vasily Gorbik Signed-off-by: Sven Schnelle Signed-off-by: Greg Kroah-Hartman --- arch/s390/boot/ipl_report.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/arch/s390/boot/ipl_report.c +++ b/arch/s390/boot/ipl_report.c @@ -57,11 +57,19 @@ repeat: if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && INITRD_START && INITRD_SIZE && intersects(INITRD_START, INITRD_SIZE, safe_addr, size)) safe_addr = INITRD_START + INITRD_SIZE; + if (intersects(safe_addr, size, (unsigned long)comps, comps->len)) { + safe_addr = (unsigned long)comps + comps->len; + goto repeat; + } for_each_rb_entry(comp, comps) if (intersects(safe_addr, size, comp->addr, comp->len)) { safe_addr = comp->addr + comp->len; goto repeat; } + if (intersects(safe_addr, size, (unsigned long)certs, certs->len)) { + safe_addr = (unsigned long)certs + certs->len; + goto repeat; + } for_each_rb_entry(cert, certs) if (intersects(safe_addr, size, cert->addr, cert->len)) { safe_addr = cert->addr + cert->len;