From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Cox Subject: [PATCH 4/4] intel, gma500, lvds: Fix use after free and mem leak in psb_intel_lvds_init() Date: Thu, 02 Feb 2012 15:19:13 +0000 Message-ID: <20120202151911.20683.22832.stgit@bob.linux.org.uk> References: <20120202151821.20683.87619.stgit@bob.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from lxorguk.ukuu.org.uk (lxorguk.ukuu.org.uk [81.2.110.251]) by gabe.freedesktop.org (Postfix) with ESMTP id 4EB18A10D1 for ; Thu, 2 Feb 2012 07:05:32 -0800 (PST) In-Reply-To: <20120202151821.20683.87619.stgit@bob.linux.org.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org Errors-To: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org To: airlied@linux.ie, dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org From: Jesper Juhl In psb_intel_lvds_init(), if we fail to allocate memory for 'psb_intel_connector' we free the memory we previously allocated for 'psb_intel_encoder', but we then proceed to use that free'd pointer when we do 'psb_intel_encoder->dev_priv = lvds_priv;'. We may also leak the memory we allocated for 'psb_intel_encoder' if we 'goto failed_connector;' and the variable goes out of scope. While I was there anyway, I also removed the pointless 'if (psb_intel_connector)' before freeing it at the 'failed_connector:' label - kfree() deals gracefully with NULL pointers, so it is not needed. Signed-off-by: Jesper Juhl Signed-off-by: Alan Cox --- drivers/gpu/drm/gma500/psb_intel_lvds.c | 9 ++++----- 1 files changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/gma500/psb_intel_lvds.c b/drivers/gpu/drm/gma500/psb_intel_lvds.c index 69a9651..c83f5b5 100644 --- a/drivers/gpu/drm/gma500/psb_intel_lvds.c +++ b/drivers/gpu/drm/gma500/psb_intel_lvds.c @@ -713,7 +713,6 @@ void psb_intel_lvds_init(struct drm_device *dev, psb_intel_encoder = kzalloc(sizeof(struct psb_intel_encoder), GFP_KERNEL); - if (!psb_intel_encoder) { dev_err(dev->dev, "psb_intel_encoder allocation error\n"); return; @@ -721,10 +720,9 @@ void psb_intel_lvds_init(struct drm_device *dev, psb_intel_connector = kzalloc(sizeof(struct psb_intel_connector), GFP_KERNEL); - if (!psb_intel_connector) { - kfree(psb_intel_encoder); dev_err(dev->dev, "psb_intel_connector allocation error\n"); + goto failed_encoder; } lvds_priv = kzalloc(sizeof(struct psb_intel_lvds_priv), GFP_KERNEL); @@ -862,7 +860,8 @@ failed_blc_i2c: drm_encoder_cleanup(encoder); drm_connector_cleanup(connector); failed_connector: - if (psb_intel_connector) - kfree(psb_intel_connector); + kfree(psb_intel_connector); +failed_encoder: + kfree(psb_intel_encoder); }