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 91B796FA0 for ; Mon, 16 Jan 2023 16:45:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 13C52C433EF; Mon, 16 Jan 2023 16:45:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1673887534; bh=yfYKLDFR2IdTdgLCIsR/pzu1cmNuilql0g+Fs8bUhXA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h6GCejRJkxZG0kmXhNASyEweHbmDzftB1Yx4AXsjhG+hliEBmQ9i7F02IxErVwpoh GfKeGGqezjkcoSvKR4a/DNQ3ZMtH5Oc27HhBWo3s75+Z6pxHj85wpB0lXyEmCFl/9x HHRnIQiqkdLul2Gf8fhbZJK77u6n3ATNGQDMU3is= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Harshit Mogalapalli , Douglas Gilbert , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.19 185/521] scsi: scsi_debug: Fix a warning in resp_write_scat() Date: Mon, 16 Jan 2023 16:47:27 +0100 Message-Id: <20230116154855.338040286@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230116154847.246743274@linuxfoundation.org> References: <20230116154847.246743274@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: Harshit Mogalapalli [ Upstream commit 216e179724c1d9f57a8ababf8bd7aaabef67f01b ] As 'lbdof_blen' is coming from user, if the size in kzalloc() is >= MAX_ORDER then we hit a warning. Call trace: sg_ioctl sg_ioctl_common scsi_ioctl sg_scsi_ioctl blk_execute_rq blk_mq_sched_insert_request blk_mq_run_hw_queue __blk_mq_delay_run_hw_queue __blk_mq_run_hw_queue blk_mq_sched_dispatch_requests __blk_mq_sched_dispatch_requests blk_mq_dispatch_rq_list scsi_queue_rq scsi_dispatch_cmd scsi_debug_queuecommand schedule_resp resp_write_scat If you try to allocate a memory larger than(>=) MAX_ORDER, then kmalloc() will definitely fail. It creates a stack trace and messes up dmesg. The user controls the size here so if they specify a too large size it will fail. Add __GFP_NOWARN in order to avoid too large allocation warning. This is detected by static analysis using smatch. Fixes: 481b5e5c7949 ("scsi: scsi_debug: add resp_write_scat function") Signed-off-by: Harshit Mogalapalli Link: https://lore.kernel.org/r/20221111100526.1790533-1-harshit.m.mogalapalli@oracle.com Acked-by: Douglas Gilbert Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/scsi_debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 4d73a7f67dea..0733ecc9f878 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -3156,7 +3156,7 @@ static int resp_write_scat(struct scsi_cmnd *scp, mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0); return illegal_condition_result; } - lrdp = kzalloc(lbdof_blen, GFP_ATOMIC); + lrdp = kzalloc(lbdof_blen, GFP_ATOMIC | __GFP_NOWARN); if (lrdp == NULL) return SCSI_MLQUEUE_HOST_BUSY; if (sdebug_verbose) -- 2.35.1