From patchwork Sun Feb 6 15:50:24 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrea Righi X-Patchwork-Id: 535201 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p16FwFWb027833 for ; Sun, 6 Feb 2011 15:58:16 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752841Ab1BFP6O (ORCPT ); Sun, 6 Feb 2011 10:58:14 -0500 Received: from trinity.develer.com ([83.149.158.210]:48377 "EHLO trinity.develer.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752839Ab1BFP6O (ORCPT ); Sun, 6 Feb 2011 10:58:14 -0500 X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Sun, 06 Feb 2011 15:58:17 +0000 (UTC) X-Greylist: delayed 462 seconds by postgrey-1.27 at vger.kernel.org; Sun, 06 Feb 2011 10:58:14 EST Received: from linux.localdomain6 (host93-4-dynamic.9-79-r.retail.telecomitalia.it [79.9.4.93]) (Authenticated sender: arighi) by trinity.develer.com (Postfix) with ESMTPSA id CA37B621FF1; Sun, 6 Feb 2011 16:50:30 +0100 (CET) From: Andrea Righi To: Andrew Morton Cc: Greg KH , =?UTF-8?q?Peter=20Nordstr=C3=B6m=20=28Palm=20GBU=29?= , linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@kernel.org Subject: [PATCH] fb: fix potential deadlock between lock_fb_info and console_lock Date: Sun, 6 Feb 2011 16:50:24 +0100 Message-Id: <1297007424-14656-1-git-send-email-arighi@develer.com> X-Mailer: git-send-email 1.7.1 MIME-Version: 1.0 Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index e2bf953..def59f0 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1034,14 +1034,16 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, case FBIOPUT_VSCREENINFO: if (copy_from_user(&var, argp, sizeof(var))) return -EFAULT; - if (!lock_fb_info(info)) - return -ENODEV; console_lock(); + if (!lock_fb_info(info)) { + console_unlock(); + return -ENODEV; + } info->flags |= FBINFO_MISC_USEREVENT; ret = fb_set_var(info, &var); info->flags &= ~FBINFO_MISC_USEREVENT; - console_unlock(); unlock_fb_info(info); + console_unlock(); if (!ret && copy_to_user(argp, &var, sizeof(var))) ret = -EFAULT; break; @@ -1070,12 +1072,14 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, case FBIOPAN_DISPLAY: if (copy_from_user(&var, argp, sizeof(var))) return -EFAULT; - if (!lock_fb_info(info)) - return -ENODEV; console_lock(); + if (!lock_fb_info(info)) { + console_unlock(); + return -ENODEV; + } ret = fb_pan_display(info, &var); - console_unlock(); unlock_fb_info(info); + console_unlock(); if (ret == 0 && copy_to_user(argp, &var, sizeof(var))) return -EFAULT; break; @@ -1117,14 +1121,16 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, unlock_fb_info(info); break; case FBIOBLANK: - if (!lock_fb_info(info)) - return -ENODEV; console_lock(); + if (!lock_fb_info(info)) { + console_unlock(); + return -ENODEV; + } info->flags |= FBINFO_MISC_USEREVENT; ret = fb_blank(info, arg); info->flags &= ~FBINFO_MISC_USEREVENT; - console_unlock(); unlock_fb_info(info); + console_unlock(); break; default: if (!lock_fb_info(info))