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 B45AD882B for ; Fri, 10 Mar 2023 15:09:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1FD7FC433D2; Fri, 10 Mar 2023 15:09:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678460955; bh=tw+6G/rxqMb1GJYc5EqdCAGNkOYKA6VdtFu9kSDFbyQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jQTWBkuvUPwwtLVht9z+Iq0kM/8RmbxjNrefkg7Eg5XRIGC6rrDixO1kAcw9K/6aK yGrLqRpuUb8DCPnOkijKpqqozd5VBFm5BWUr5eFHJtCQnjhrs4bII5N5iqWhxPTX0C KvJH5eMwSjK5s4O+NY4nliUMmsGWQRoq+x+dUCcM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhong Jinghua , Chaitanya Kulkarni , Jens Axboe , Sasha Levin Subject: [PATCH 5.10 477/529] loop: loop_set_status_from_info() check before assignment Date: Fri, 10 Mar 2023 14:40:20 +0100 Message-Id: <20230310133826.952431571@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133804.978589368@linuxfoundation.org> References: <20230310133804.978589368@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: Zhong Jinghua [ Upstream commit 9f6ad5d533d1c71e51bdd06a5712c4fbc8768dfa ] In loop_set_status_from_info(), lo->lo_offset and lo->lo_sizelimit should be checked before reassignment, because if an overflow error occurs, the original correct value will be changed to the wrong value, and it will not be changed back. More, the original patch did not solve the problem, the value was set and ioctl returned an error, but the subsequent io used the value in the loop driver, which still caused an alarm: loop_handle_cmd do_req_filebacked loff_t pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset; lo_rw_aio cmd->iocb.ki_pos = pos Fixes: c490a0b5a4f3 ("loop: Check for overflow while configuring loop") Signed-off-by: Zhong Jinghua Reviewed-by: Chaitanya Kulkarni Link: https://lore.kernel.org/r/20230221095027.3656193-1-zhongjinghua@huaweicloud.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/block/loop.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index b10410585a746..d86fbea54652a 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1029,13 +1029,13 @@ loop_set_status_from_info(struct loop_device *lo, if (err) return err; + /* Avoid assigning overflow values */ + if (info->lo_offset > LLONG_MAX || info->lo_sizelimit > LLONG_MAX) + return -EOVERFLOW; + lo->lo_offset = info->lo_offset; lo->lo_sizelimit = info->lo_sizelimit; - /* loff_t vars have been assigned __u64 */ - if (lo->lo_offset < 0 || lo->lo_sizelimit < 0) - return -EOVERFLOW; - memcpy(lo->lo_file_name, info->lo_file_name, LO_NAME_SIZE); memcpy(lo->lo_crypt_name, info->lo_crypt_name, LO_NAME_SIZE); lo->lo_file_name[LO_NAME_SIZE-1] = 0; -- 2.39.2