From: Al Viro <viro@ZenIV.linux.org.uk>
To: David Howells <dhowells@redhat.com>
Cc: mszeredi@redhat.com, linux-nfs@vger.kernel.org,
jlayton@redhat.com, linux-kernel@vger.kernel.org,
linux-security-module@vger.kernel.org,
linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 07/27] VFS: Differentiate mount flags (MS_*) from internal superblock flags [ver #5]
Date: Thu, 15 Jun 2017 10:39:27 +0100 [thread overview]
Message-ID: <20170615093927.GG31671@ZenIV.linux.org.uk> (raw)
In-Reply-To: <149745338248.10897.17175227466711674034.stgit@warthog.procyon.org.uk>
On Wed, Jun 14, 2017 at 04:16:22PM +0100, David Howells wrote:
> diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
> index d2fb9c8ed205..e831c115daf9 100644
> --- a/drivers/base/devtmpfs.c
> +++ b/drivers/base/devtmpfs.c
> @@ -355,7 +355,7 @@ int devtmpfs_mount(const char *mntdir)
> if (!thread)
> return 0;
>
> - err = sys_mount("devtmpfs", (char *)mntdir, "devtmpfs", MS_SILENT, NULL);
> + err = sys_mount("devtmpfs", (char *)mntdir, "devtmpfs", SB_SILENT, NULL);
> if (err)
> printk(KERN_INFO "devtmpfs: error mounting %i\n", err);
> else
> @@ -381,7 +381,7 @@ static int devtmpfsd(void *p)
> *err = sys_unshare(CLONE_NEWNS);
> if (*err)
> goto out;
> - *err = sys_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, options);
> + *err = sys_mount("devtmpfs", "/", "devtmpfs", SB_SILENT, options);
Er... These really should be MS_SILENT.
> @@ -311,14 +311,14 @@ static void get_dpms_capabilities(unsigned char flags,
> struct fb_monspecs *specs)
> {
> specs->dpms = 0;
> - if (flags & DPMS_ACTIVE_OFF)
> - specs->dpms |= FB_DPMS_ACTIVE_OFF;
> + if (flags & DPSB_ACTIVE_OFF)
> + specs->dpms |= FB_DPSB_ACTIVE_OFF;
... the hell?
> - if (sb->s_flags & MS_RDONLY)
> + if (sb->s_flags & SB_RDONLY)
TBH, it looks like something along the lines of sb_rdonly(sb) for the above would
make more sense.
> static int flags_to_propagation_type(int flags)
> {
> - int type = flags & ~(MS_REC | MS_SILENT);
> + int type = flags & ~(MS_REC | SB_SILENT);
Huh?
> - flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE | MS_BORN |
> - MS_NOATIME | MS_NODIRATIME | MS_RELATIME| MS_KERNMOUNT |
> - MS_STRICTATIME | MS_NOREMOTELOCK | MS_SUBMOUNT);
> + flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | SB_ACTIVE | SB_BORN |
> + MS_NOATIME | MS_NODIRATIME | MS_RELATIME| SB_KERNMOUNT |
> + MS_STRICTATIME | SB_NOREMOTELOCK | SB_SUBMOUNT);
This is complete bullshit. _IF_ you want to separate these sets, do that
consistently. Mixing MS_... with SB_... in a mask is obviously wrong.
Sure, you can use the fact that such-and-such SB_ flag is the same value
as MS_... one; worth a BUILD_BUG_ON() somewhere to enforce that. However,
please separate the places where you have mount(2) flags argument from
those where you have a set of SB_... bits.
In this case you certainly have MS_... bunch. What's more, I would rather
do it as "we look only at..." instead of "we ignore the following..." - and
probably do it in do_...() functions instead. Note that they already
have parsing and validation of their own...
> diff --git a/tools/testing/selftests/mount/unprivileged-remount-test.c b/tools/testing/selftests/mount/unprivileged-remount-test.c
> index 517785052f1c..65489157f8d7 100644
> --- a/tools/testing/selftests/mount/unprivileged-remount-test.c
> +++ b/tools/testing/selftests/mount/unprivileged-remount-test.c
> @@ -129,7 +129,7 @@ static int read_mnt_flags(const char *path)
> }
> mnt_flags = 0;
> if (stat.f_flag & ST_RDONLY)
> - mnt_flags |= MS_RDONLY;
> + mnt_flags |= SB_RDONLY;
> if (stat.f_flag & ST_NOSUID)
> mnt_flags |= MS_NOSUID;
> if (stat.f_flag & ST_NODEV)
> @@ -143,7 +143,7 @@ static int read_mnt_flags(const char *path)
> if (stat.f_flag & ST_RELATIME)
> mnt_flags |= MS_RELATIME;
> if (stat.f_flag & ST_SYNCHRONOUS)
> - mnt_flags |= MS_SYNCHRONOUS;
> + mnt_flags |= SB_SYNCHRONOUS;
> if (stat.f_flag & ST_MANDLOCK)
> mnt_flags |= ST_MANDLOCK;
Really? That's userland code, isn't it?
next prev parent reply other threads:[~2017-06-15 9:39 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-06-14 15:15 [RFC][PATCH 00/27] VFS: Introduce filesystem context [ver #5] David Howells
2017-06-14 15:15 ` [PATCH 01/27] Provide a function to create a NUL-terminated string from unterminated data " David Howells
2017-06-14 15:15 ` [PATCH 02/27] VFS: Clean up whitespace in fs/namespace.c and fs/super.c " David Howells
2017-06-14 15:15 ` [PATCH 03/27] VFS: Make get_mnt_ns() return the namespace " David Howells
2017-06-15 9:09 ` Al Viro
2017-06-14 15:15 ` [PATCH 04/27] VFS: Make get_filesystem() return the affected filesystem " David Howells
2017-06-14 15:16 ` [PATCH 05/27] VFS: Provide empty name qstr " David Howells
2017-06-14 15:16 ` [PATCH 06/27] Provide supplementary error message facility " David Howells
2017-08-18 3:09 ` Kim Phillips
2017-06-14 15:16 ` [PATCH 07/27] VFS: Differentiate mount flags (MS_*) from internal superblock flags " David Howells
2017-06-15 9:39 ` Al Viro [this message]
2017-06-16 9:06 ` Christoph Hellwig
2017-06-16 14:53 ` David Howells
2017-06-16 15:49 ` Christoph Hellwig
2017-06-16 15:54 ` David Howells
2017-06-14 15:16 ` [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context " David Howells
2017-06-14 18:02 ` Randy Dunlap
2017-06-14 20:03 ` Casey Schaufler
2017-06-14 20:42 ` David Howells
2017-06-14 20:53 ` Casey Schaufler
2017-06-17 9:57 ` Theodore Ts'o
2017-06-17 14:18 ` David Howells
2017-06-17 14:56 ` Jeff Layton
2017-06-17 15:11 ` Randy Dunlap
2017-06-19 7:47 ` David Howells
2017-06-14 22:58 ` Updated docs David Howells
2017-06-15 1:53 ` Randy Dunlap
2017-06-14 15:16 ` [PATCH 09/27] VFS: Add LSM hooks for filesystem context [ver #5] David Howells
2017-06-14 15:16 ` [PATCH 10/27] VFS: Implement a filesystem superblock creation/configuration " David Howells
2017-06-14 15:17 ` [PATCH 11/27] VFS: Remove unused code after filesystem context changes " David Howells
2017-06-14 15:17 ` [PATCH 12/27] VFS: Implement fsopen() to prepare for a mount " David Howells
2017-06-14 15:17 ` [PATCH 13/27] VFS: Implement fsmount() to effect a pre-configured " David Howells
2017-06-14 15:17 ` [PATCH 14/27] VFS: Add a sample program for fsopen/fsmount " David Howells
2017-06-14 15:17 ` [PATCH 15/27] procfs: Move proc_fill_super() to fs/proc/root.c " David Howells
2017-06-14 15:17 ` [PATCH 16/27] proc: Add fs_context support to procfs " David Howells
2017-06-15 10:14 ` Al Viro
2017-06-14 15:17 ` [PATCH 17/27] NFS: Move mount parameterisation bits into their own file " David Howells
2017-06-14 15:18 ` [PATCH 18/27] NFS: Constify mount argument match tables " David Howells
2017-06-14 15:18 ` [PATCH 19/27] NFS: Rename struct nfs_parsed_mount_data to struct nfs_fs_context " David Howells
2017-06-14 15:18 ` [PATCH 20/27] NFS: Split nfs_parse_mount_options() " David Howells
2017-06-14 15:18 ` [PATCH 21/27] NFS: Deindent nfs_fs_context_parse_option() " David Howells
2017-06-14 15:18 ` [PATCH 22/27] NFS: Add a small buffer in nfs_fs_context to avoid string dup " David Howells
2017-06-14 15:18 ` [PATCH 23/27] NFS: Do some tidying of the parsing code " David Howells
2017-06-14 15:18 ` [PATCH 24/27] NFS: Add fs_context support. " David Howells
2017-06-15 15:28 ` Anna Schumaker
2017-06-14 15:19 ` [PATCH 25/27] ipc: Convert mqueue fs to fs_context " David Howells
2017-06-15 10:07 ` Al Viro
2017-06-15 14:47 ` David Howells
2017-06-14 15:19 ` [PATCH 26/27] cpuset: Use " David Howells
2017-06-14 15:19 ` [PATCH 27/27] kernfs, sysfs, cgroup: Support " David Howells
2017-06-14 17:54 ` Tejun Heo
2017-06-23 15:29 ` David Howells
2017-06-14 22:31 ` [PATCH 27/27] ... and the intel_rdt driver David Howells
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