From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: sbrabec@suse.cz Subject: Re: [PATCH] Fix possible NULL dereference in get_btrfs_fs_root() To: Karel Zak References: <56FC3BE7.7040001@suse.cz> <20160331095433.kt6skftq5agqrxje@ws.net.home> Cc: util-linux@vger.kernel.org From: Stanislav Brabec Message-ID: <56FE7ECD.2040804@suse.cz> Date: Fri, 1 Apr 2016 15:59:41 +0200 MIME-Version: 1.0 In-Reply-To: <20160331095433.kt6skftq5agqrxje@ws.net.home> Content-Type: text/plain; charset=windows-1252; format=flowed List-ID: On Mar 31, 2016 at 11:54 Karel Zak wrote: > On Wed, Mar 30, 2016 at 10:49:43PM +0200, Stanislav Brabec wrote: >> set_fs_root() got it as upd->mountinfo being NULL from utab_new_entry(). That >> got it from mnt_update_set_fs(), that from mnt_context_prepare_update() (where >> it is cxt->update->mountinfo). >> >> At least the constructor mnt_new_update() can create context with cxt->update >> being not NULL and cxt->update->mountinfo being NULL. >> >> It is also possible to pass to mnt_context_prepare_update() with cxt->update not >> being NULL but cxt->update->mountinfo being NULL created by mnt_new_context(), >> e. g. from mnt_context_mount(). > > It's seems better to read mountinfo when really necessary than always. > I have applied something else: > > https://github.com/karelzak/util-linux/commit/e9cd2e2bd9ec91a0b1050c4aa79555d142985924 I just got a positive feedback. My original patch as well as your patch fix the crash. Thanks. -- Best Regards / S pozdravem, Stanislav Brabec software developer --------------------------------------------------------------------- SUSE LINUX, s. r. o. e-mail: sbrabec@suse.com Lihovarská 1060/12 tel: +49 911 7405384547 190 00 Praha 9 fax: +420 284 084 001 Czech Republic http://www.suse.cz/ PGP: 830B 40D5 9E05 35D8 5E27 6FA3 717C 209F A04F CD76