Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752742AbdGSAIQ (ORCPT ); Tue, 18 Jul 2017 20:08:16 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:41835 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752070AbdGSAIO (ORCPT ); Tue, 18 Jul 2017 20:08:14 -0400 Subject: Re: [PATCH v3 02/15] exec: Rename bprm->cred_prepared to called_set_creds To: Kees Cook , Andrew Morton Cc: David Howells , Paul Moore , Stephen Smalley , Casey Schaufler , James Morris , "Eric W. Biederman" , "Serge E. Hallyn" , Tetsuo Handa , Andy Lutomirski , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org References: <1500416736-49829-1-git-send-email-keescook@chromium.org> <1500416736-49829-3-git-send-email-keescook@chromium.org> From: John Johansen Organization: Canonical Message-ID: Date: Tue, 18 Jul 2017 17:08:08 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <1500416736-49829-3-git-send-email-keescook@chromium.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4449 Lines: 125 On 07/18/2017 03:25 PM, Kees Cook wrote: > The cred_prepared bprm flag has a misleading name. It has nothing to do > with the bprm_prepare_cred hook, and actually tracks if bprm_set_creds has > been called. Rename this flag and improve its comment. > > Cc: David Howells > Cc: John Johansen > Cc: Paul Moore > Cc: Stephen Smalley > Cc: Casey Schaufler > Cc: James Morris > Signed-off-by: Kees Cook looks good Acked-by: John Johansen > --- > fs/binfmt_flat.c | 2 +- > fs/exec.c | 2 +- > include/linux/binfmts.h | 8 ++++++-- > security/apparmor/domain.c | 2 +- > security/selinux/hooks.c | 2 +- > security/smack/smack_lsm.c | 2 +- > security/tomoyo/tomoyo.c | 2 +- > 7 files changed, 12 insertions(+), 8 deletions(-) > > diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c > index 2edcefc0a294..a722530cc468 100644 > --- a/fs/binfmt_flat.c > +++ b/fs/binfmt_flat.c > @@ -885,7 +885,7 @@ static int load_flat_shared_library(int id, struct lib_info *libs) > * as we're past the point of no return and are dealing with shared > * libraries. > */ > - bprm.cred_prepared = 1; > + bprm.called_set_creds = 1; > > res = prepare_binprm(&bprm); > > diff --git a/fs/exec.c b/fs/exec.c > index 904199086490..925c85a45d97 100644 > --- a/fs/exec.c > +++ b/fs/exec.c > @@ -1547,7 +1547,7 @@ int prepare_binprm(struct linux_binprm *bprm) > retval = security_bprm_set_creds(bprm); > if (retval) > return retval; > - bprm->cred_prepared = 1; > + bprm->called_set_creds = 1; > > memset(bprm->buf, 0, BINPRM_BUF_SIZE); > return kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE); > diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h > index 9508b5f83c7e..36be5a67517a 100644 > --- a/include/linux/binfmts.h > +++ b/include/linux/binfmts.h > @@ -25,8 +25,12 @@ struct linux_binprm { > struct mm_struct *mm; > unsigned long p; /* current top of mem */ > unsigned int > - cred_prepared:1,/* true if creds already prepared (multiple > - * preps happen for interpreters) */ > + /* > + * True after the bprm_set_creds hook has been called once > + * (multiple calls can be made via prepare_binprm() for > + * binfmt_script/misc). > + */ > + called_set_creds:1, > cap_effective:1,/* true if has elevated effective capabilities, > * false if not; except for init which inherits > * its parent's caps anyway */ > diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c > index 001e133a3c8c..878407e023e3 100644 > --- a/security/apparmor/domain.c > +++ b/security/apparmor/domain.c > @@ -350,7 +350,7 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm) > const char *name = NULL, *info = NULL; > int error = 0; > > - if (bprm->cred_prepared) > + if (bprm->called_set_creds) > return 0; > > ctx = cred_ctx(bprm->cred); > diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c > index 819fd6858b49..0f1450a06b02 100644 > --- a/security/selinux/hooks.c > +++ b/security/selinux/hooks.c > @@ -2327,7 +2327,7 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm) > > /* SELinux context only depends on initial program or script and not > * the script interpreter */ > - if (bprm->cred_prepared) > + if (bprm->called_set_creds) > return 0; > > old_tsec = current_security(); > diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c > index 658f5d8c7e76..7d4b2e221124 100644 > --- a/security/smack/smack_lsm.c > +++ b/security/smack/smack_lsm.c > @@ -917,7 +917,7 @@ static int smack_bprm_set_creds(struct linux_binprm *bprm) > struct superblock_smack *sbsp; > int rc; > > - if (bprm->cred_prepared) > + if (bprm->called_set_creds) > return 0; > > isp = inode->i_security; > diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c > index 130b4fa4f65f..d25b705360e0 100644 > --- a/security/tomoyo/tomoyo.c > +++ b/security/tomoyo/tomoyo.c > @@ -76,7 +76,7 @@ static int tomoyo_bprm_set_creds(struct linux_binprm *bprm) > * Do only if this function is called for the first time of an execve > * operation. > */ > - if (bprm->cred_prepared) > + if (bprm->called_set_creds) > return 0; > #ifndef CONFIG_SECURITY_TOMOYO_OMIT_USERSPACE_LOADER > /* >