From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= Date: Tue, 25 Jun 2019 23:52:30 +0200 Message-Id: <20190625215239.11136-2-mic@digikod.net> In-Reply-To: <20190625215239.11136-1-mic@digikod.net> References: <20190625215239.11136-1-mic@digikod.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-api-owner@vger.kernel.org Subject: [PATCH bpf-next v9 01/10] fs,security: Add a new file access type: MAY_CHROOT Content-Transfer-Encoding: 8bit To: linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= , Aleksa Sarai , Alexander Viro , Alexei Starovoitov , Andrew Morton , Andy Lutomirski , Arnaldo Carvalho de Melo , Casey Schaufler , Daniel Borkmann , David Drysdale , "David S . Miller" , "Eric W . Biederman" , James Morris , Jann Horn , John Johansen , Jonathan Corbet , Kees Cook , Michael Kerrisk , =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= , Paul Moore , Sargun Dhillon , "Serge E . Hallyn" , Shuah Khan , Stephen Smalley , Tejun Heo , Tetsuo Handa , Thomas Graf , Tycho Andersen , Will Drewry , kernel-hardening@lists.openwall.com, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, netdev@vger.kernel.org List-ID: For compatibility reason, MAY_CHROOT is always set with MAY_CHDIR. However, this new flag enable to differentiate a chdir form a chroot. This is needed for the Landlock LSM to be able to evaluate a new root directory. Signed-off-by: Mickaël Salaün Cc: Alexander Viro Cc: Casey Schaufler Cc: James Morris Cc: John Johansen Cc: Kees Cook Cc: Paul Moore Cc: "Serge E. Hallyn" Cc: Stephen Smalley Cc: Tetsuo Handa Cc: linux-fsdevel@vger.kernel.org --- fs/open.c | 3 ++- include/linux/fs.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/open.c b/fs/open.c index b5b80469b93d..e8767318fd03 100644 --- a/fs/open.c +++ b/fs/open.c @@ -494,7 +494,8 @@ int ksys_chroot(const char __user *filename) if (error) goto out; - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR); + error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR | + MAY_CHROOT); if (error) goto dput_and_out; diff --git a/include/linux/fs.h b/include/linux/fs.h index f7fdfe93e25d..fa6c9d0c152b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -99,6 +99,7 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset, #define MAY_CHDIR 0x00000040 /* called from RCU mode, don't block */ #define MAY_NOT_BLOCK 0x00000080 +#define MAY_CHROOT 0x00000100 /* * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond -- 2.20.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= Subject: [PATCH bpf-next v9 01/10] fs,security: Add a new file access type: MAY_CHROOT Date: Tue, 25 Jun 2019 23:52:30 +0200 Message-ID: <20190625215239.11136-2-mic@digikod.net> References: <20190625215239.11136-1-mic@digikod.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: List-Post: List-Help: List-Unsubscribe: List-Subscribe: In-Reply-To: <20190625215239.11136-1-mic@digikod.net> To: linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= , Aleksa Sarai , Alexander Viro , Alexei Starovoitov , Andrew Morton , Andy Lutomirski , Arnaldo Carvalho de Melo , Casey Schaufler , Daniel Borkmann , David Drysdale , "David S . Miller" , "Eric W . Biederman" , James Morris , Jann Horn , John Johansen , Jonathan Corbet , Kees Cook , Michael Kerrisk , =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= List-Id: linux-api@vger.kernel.org For compatibility reason, MAY_CHROOT is always set with MAY_CHDIR. However, this new flag enable to differentiate a chdir form a chroot. This is needed for the Landlock LSM to be able to evaluate a new root directory. Signed-off-by: Mickaël Salaün Cc: Alexander Viro Cc: Casey Schaufler Cc: James Morris Cc: John Johansen Cc: Kees Cook Cc: Paul Moore Cc: "Serge E. Hallyn" Cc: Stephen Smalley Cc: Tetsuo Handa Cc: linux-fsdevel@vger.kernel.org --- fs/open.c | 3 ++- include/linux/fs.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/open.c b/fs/open.c index b5b80469b93d..e8767318fd03 100644 --- a/fs/open.c +++ b/fs/open.c @@ -494,7 +494,8 @@ int ksys_chroot(const char __user *filename) if (error) goto out; - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR); + error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR | + MAY_CHROOT); if (error) goto dput_and_out; diff --git a/include/linux/fs.h b/include/linux/fs.h index f7fdfe93e25d..fa6c9d0c152b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -99,6 +99,7 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset, #define MAY_CHDIR 0x00000040 /* called from RCU mode, don't block */ #define MAY_NOT_BLOCK 0x00000080 +#define MAY_CHROOT 0x00000100 /* * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond -- 2.20.1