Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753295Ab0FWNVg (ORCPT ); Wed, 23 Jun 2010 09:21:36 -0400 Received: from hapkido.dreamhost.com ([66.33.216.122]:55115 "EHLO hapkido.dreamhost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752748Ab0FWNVf (ORCPT ); Wed, 23 Jun 2010 09:21:35 -0400 Subject: Re: [PATCH fs/ramfs] inode.c: Fix incorrect variable freeing. From: Davidlohr Bueso Reply-To: dave.bueso@gmail.com To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org In-Reply-To: <20100622124101.0dbb2b3c.akpm@linux-foundation.org> References: <1277062057.14428.0.camel@cowboy> <20100622124101.0dbb2b3c.akpm@linux-foundation.org> Content-Type: text/plain; charset="UTF-8" Date: Wed, 23 Jun 2010 09:20:46 -0400 Message-ID: <1277299246.17913.0.camel@cowboy> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1785 Lines: 58 On Tue, 2010-06-22 at 12:41 -0700, Andrew Morton wrote: > On Sun, 20 Jun 2010 15:27:37 -0400 > Davidlohr Bueso wrote: > > > Hi, > > > > In ramfs_fill_super(), if fsi's memory allocation fails, it will go to 'fail', > > which immediately tries to free the variable, potentially producing an Oops. > > This patch addresses this issue. > > > > Thanks. > > > > Signed-off-by: Davidlohr Bueso > > --- > > fs/ramfs/inode.c | 8 +++++--- > > 1 files changed, 5 insertions(+), 3 deletions(-) > > > > diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c > > index a5ebae7..40af7a2 100644 > > --- a/fs/ramfs/inode.c > > +++ b/fs/ramfs/inode.c > > @@ -219,7 +219,7 @@ int ramfs_fill_super(struct super_block *sb, void *data, int silent) > > sb->s_fs_info = fsi; > > if (!fsi) { > > err = -ENOMEM; > > - goto fail; > > + goto fail2; > > } > > > > err = ramfs_parse_options(data, &fsi->mount_opts); > > @@ -247,11 +247,13 @@ int ramfs_fill_super(struct super_block *sb, void *data, int silent) > > } > > > > return 0; > > -fail: > > - kfree(fsi); > > +fail2: > > sb->s_fs_info = NULL; > > iput(inode); > > return err; > > +fail: > > + kfree(fsi); > > + goto fail2; > > } > > > > int ramfs_get_sb(struct file_system_type *fs_type, > > notabug. kfree(NULL) is an OK thing to do. The kernel does this > pretty regularly in recovery paths - it usually results in slightly > simpler and slightly smaller code. Yeah I kind of knew that but slipped my mind. Sorry for the noise. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/