From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Ts'o Subject: Re: [PATCH] ext4: fixed ext4_calculate_overhead() bug. Date: Wed, 28 Nov 2012 12:45:15 -0500 Message-ID: <20121128174515.GC24431@thunk.org> References: <1353544101-5154-1-git-send-email-vmartirosyan@linuxtesting.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Vahram Martirosyan , Andreas Dilger , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org To: Vahram Martirosyan Return-path: Content-Disposition: inline In-Reply-To: <1353544101-5154-1-git-send-email-vmartirosyan@linuxtesting.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Wed, Nov 21, 2012 at 04:28:21PM -0800, Vahram Martirosyan wrote: > The memset operation before check brings to a BUG. > No need to memset the page with zeroes. > > The patch removes the memset call in ext4_calculate_overhead() function. > > Found by the Spruce system in cooperation with the KEDR Framework. > > Signed-off-by: Vahram Martirosyan Applied, with a slightly rewritten commit description: ext4: fixed potential NULL dereference in ext4_calculate_overhead() The memset operation before check can cause a BUG if the memory allocation failed. Since we are using get_zeroed_age, there is no need to use memset anyway. Found by the Spruce system in cooperation with the KEDR Framework. Signed-off-by: Vahram Martirosyan Signed-off-by: "Theodore Ts'o" - Ted