From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932381AbdA3QCg (ORCPT ); Mon, 30 Jan 2017 11:02:36 -0500 Received: from mailout2.samsung.com ([203.254.224.25]:59561 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753632AbdA3QC1 (ORCPT ); Mon, 30 Jan 2017 11:02:27 -0500 X-AuditID: b6c32a2e-f79656d0000012f2-10-588f62dea9bd From: Bartlomiej Zolnierkiewicz To: Arvind Yadav Cc: jejb@parisc-linux.org, deller@gmx.de, linux-parisc@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] video : fbdev : stifb :- Handle return NULL error from ioremap_nocache. Date: Mon, 30 Jan 2017 16:59:22 +0100 Message-id: <1759269.Z5Z5RrJiUP@amdc3058> User-Agent: KMail/4.13.3 (Linux/3.13.0-96-generic; KDE/4.13.3; x86_64; ; ) In-reply-to: <1484734911-5299-1-git-send-email-arvind.yadav.cs@gmail.com> MIME-version: 1.0 Content-transfer-encoding: 7Bit Content-type: text/plain; charset=us-ascii X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupileLIzCtJLcpLzFFi42LZdlhTQ/deUn+Ewf+p6hbXehcyW9z/dJvR 4v66VawWJ/o+sFpc3jWHzeLRqQtMDmweO2fdZff48DHO48Ki36wenzfJBbBEcdmkpOZklqUW 6dslcGW8vHWOpeA3b8XL92cZGxhfc3cxcnJICJhIXN4xkxHCFpO4cG89WxcjF4eQwFJGiV8P 3zNBOO1MEvfnnGKG6Zg8eSoLRGI5o8T0lUeYIZyvjBJT93xiAaliE7CSmNi+CmyuiICOxKaZ vxlBipgFmhklXv3sBBslLJAoMbXpOJjNIqAqcebPMbBmXgFNiW8vm9lBbFEBL4kt+9qZQGxO AU+J13caWCFqBCV+TL4HVs8sIC+xb/9UVghbR+LssXVgyyQEJrNL/N77AGgBB5AjK7HpANQL LhKnF72CsoUlXh3fwg5hS0v8XXoLGhjTGSW2/5aAmLOZUWLV7glQRdYSh49fhFrGJ9H7+wkT xHxeiY42IYgSD4nJF94yQdiOEms2/oAG1xxGiUP7LrFOYJSfheSHWUh+mIXkhwWMzKsYxVIL inPTU4tNC4z1ihNzi0vz0vWS83M3MYJTiJbeDsZ/C7wPMQpwMCrx8L7w7Y8QYk0sK67MPcQo wcGsJMIbEAcU4k1JrKxKLcqPLyrNSS0+xCjNwaIkzrugwjpCSCA9sSQ1OzW1ILUIJsvEwSnV wLhBSdkmrdxPXemaf0/GZ62QpvlvXcyitL6KXNDuyqnueS1UFFEVdoRnx3G7LzVTklmT7j+Z Gdn+886lgsbMu/F6roctn0lnnkgI1wt5XHGmgFdw/5Q6tyv1a06sKV9UGvT67BfemZFOZfUW hx2/yx/QEW9+YlT0T3jxbm2fnW+zdL4GfT22W4mlOCPRUIu5qDgRAEH+YXcdAwAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrNIsWRmVeSWpSXmKPExsVy+t9jAd27Sf0RBh//iFlc613IbHH/021G i/vrVrFanOj7wGpxedccNotHpy4wObB57Jx1l93jw8c4jwuLfrN6fN4kF8AS5WaTkZqYklqk kJqXnJ+SmZduqxQa4qZroaSQl5ibaqsUoesbEqSkUJaYUwrkGRmgAQfnAPdgJX27BLeMl7fO sRT85q14+f4sYwPja+4uRk4OCQETicmTp7JA2GISF+6tZwOxhQSWMkqc3whkcwHZXxkltu7a D5ZgE7CSmNi+ihHEFhHQkdg08zcjSBGzQDOjxPRFU5hBEsICiRLr1m0Ea2ARUJU48+cY2AZe AU2Jby+b2UFsUQEviS372plAbE4BT4nXdxpYIbbNY5SYf6UfqkFQ4sfke2A2s4C8xL79U1kh bC2J9TuPM01gFJiFpGwWkrJZSMoWMDKvYpRILUguKE5KzzXKSy3XK07MLS7NS9dLzs/dxAiO qGfSOxgP73I/xCjAwajEwzvBuz9CiDWxrLgy9xCjBAezkghvQBxQiDclsbIqtSg/vqg0J7X4 EKMp0IcTmaVEk/OB0Z5XEm9oYm5ibmxgYW5paWKkJM7bOPtZuJBAemJJanZqakFqEUwfEwen VAMjY9iJ78sFVjku4/SxZ9sqeSJBZaXhCvVTpWdP9+/vWceT8ab/7ydW9VUa/0/vju1eULe3 +HKNfmvuc/NN/0rlFXQtS/g9H0+fJlcYMF2AN1F7+jbh3Y/tKrmZON8+uuRkotFwRzUy1fDr nDX3lXkZxPcnuG9iPZv0wFz89IurV45+5xdgfZioxFKckWioxVxUnAgAYgwo6r4CAAA= X-MTR: 20000000000000000@CPGS X-CMS-MailID: 20170130155925epcas5p2eb7261871793488fb6d181ff509b469d X-Msg-Generator: CA X-Sender-IP: 203.254.230.27 X-Local-Sender: =?UTF-8?B?QmFydGxvbWllaiBab2xuaWVya2lld2ljehtTUlBPTC1LZXJu?= =?UTF-8?B?ZWwgKFRQKRvsgrzshLHsoITsnpAbU2VuaW9yIFNvZnR3YXJlIEVuZ2luZWVy?= X-Global-Sender: =?UTF-8?B?QmFydGxvbWllaiBab2xuaWVya2lld2ljehtTUlBPTC1LZXJu?= =?UTF-8?B?ZWwgKFRQKRtTYW1zdW5nIEVsZWN0cm9uaWNzG1NlbmlvciBTb2Z0d2FyZSBF?= =?UTF-8?B?bmdpbmVlcg==?= X-Sender-Code: =?UTF-8?B?QzEwG0VIURtDMTBDRDAyQ0QwMjczOTI=?= CMS-TYPE: 105P X-HopCount: 7 X-CMS-RootMailID: 20170118102229epcas1p21c74a99299ee919a3f2d28ad435b7ca7 X-RootMTR: 20170118102229epcas1p21c74a99299ee919a3f2d28ad435b7ca7 References: <1484734911-5299-1-git-send-email-arvind.yadav.cs@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wednesday, January 18, 2017 03:51:51 PM Arvind Yadav wrote: > Here, If ioremap_nocache will fail. It will return NULL. > Kernel can run into a NULL-pointer dereference. > This error check will avoid NULL pointer dereference. > > Signed-off-by: Arvind Yadav Thanks, I queued your patch with some minor changes for 4.11 (you can see the final version of the patch below). Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics From: Arvind Yadav Subject: [PATCH v1] video: fbdev: stifb: handle NULL return value from ioremap_nocache Add missing error check for ioremap_nocache() failure (prevents NULL pointer dereference on error). Cc: "James E.J. Bottomley" Cc: Helge Deller Signed-off-by: Arvind Yadav [b.zolnierkie: minor fixes] Signed-off-by: Bartlomiej Zolnierkiewicz --- drivers/video/fbdev/stifb.c | 4 ++++ 1 file changed, 4 insertions(+) Index: b/drivers/video/fbdev/stifb.c =================================================================== --- a/drivers/video/fbdev/stifb.c 2017-01-30 16:55:15.766435453 +0100 +++ b/drivers/video/fbdev/stifb.c 2017-01-30 16:55:15.750435453 +0100 @@ -1294,6 +1294,10 @@ static int __init stifb_init_fb(struct s strcpy(fix->id, "stifb"); info->fbops = &stifb_ops; info->screen_base = ioremap_nocache(REGION_BASE(fb,1), fix->smem_len); + if (!info->screen_base) { + printk(KERN_ERR "stifb: failed to map memory\n"); + goto out_err0; + } info->screen_size = fix->smem_len; info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_COPYAREA; info->pseudo_palette = &fb->pseudo_palette;