[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <e3198416-4d90-4984-88ee-d2fccf96c783@t-8ch.de>
Date: Sun, 10 Mar 2024 10:18:07 +0100
From: Thomas Weißschuh <linux@...ssschuh.net>
To: Joel Granados <j.granados@...sung.com>
Cc: Luis Chamberlain <mcgrof@...nel.org>,
Kees Cook <keescook@...omium.org>, "David S. Miller" <davem@...emloft.net>,
Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>,
Paolo Abeni <pabeni@...hat.com>, linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
netdev@...r.kernel.org
Subject: Re: [PATCH v2] sysctl: treewide: constify ctl_table_root::permissions
Hi!
On 2024-03-03 15:34:08+0100, Joel Granados wrote:
> Just to be sure I'm following. This is V2 of "[PATCH] sysctl: treewide:
> constify ctl_table_root::set_ownership". Right? I ask, because the
> subject changes slightly.
No, the v1 of this patch is linked in the patch log below.
The patches for ::set_ownership and ::permissions are changing two
different callbacks and both of them are needed.
The v2 for set_ownership is here:
https://lore.kernel.org/lkml/20240223-sysctl-const-ownership-v2-1-f9ba1795aaf2@weissschuh.net/
Regards
>
> Best
>
> On Fri, Feb 23, 2024 at 04:52:16PM +0100, Thomas Weißschuh wrote:
> > The permissions callback is not supposed to modify the ctl_table.
> > Enforce this expectation via the typesystem.
> >
> > The patch was created with the following coccinelle script:
> >
> > @@
> > identifier func, head, ctl;
> > @@
> >
> > int func(
> > struct ctl_table_header *head,
> > - struct ctl_table *ctl)
> > + const struct ctl_table *ctl)
> > { ... }
> >
> > (insert_entry() from fs/proc/proc_sysctl.c is a false-positive)
> >
> > The three changed locations were validated through manually inspection
> > and compilation.
> >
> > In addition a search for '.permissions =' was done over the full tree to
> > look for places that were missed by coccinelle.
> > None were found.
> >
> > This change also is a step to put "struct ctl_table" into .rodata
> > throughout the kernel.
> >
> > Signed-off-by: Thomas Weißschuh <linux@...ssschuh.net>
> > ---
> > To: Luis Chamberlain <mcgrof@...nel.org>
> > To: Kees Cook <keescook@...omium.org>
> > To: Joel Granados <j.granados@...sung.com>
> > To: David S. Miller <davem@...emloft.net>
> > Signed-off-by: Thomas Weißschuh <linux@...ssschuh.net>
> >
> > Changes in v2:
> > - flesh out commit messages
> > - Integrate changes to set_ownership and ctl_table_args into a single
> > series
> > - Link to v1: https://lore.kernel.org/r/20231226-sysctl-const-permissions-v1-1-5cd3c91f6299@weissschuh.net
> > ---
> > The patch is meant to be merged via the sysctl tree.
> >
> > There is an upcoming series that will introduce a new implementation of
> > .permission which would need to be adapted [0].
> > The adaption would be trivial as the 'table' parameter also not modified
> > there.
> >
> > This change was originally part of the sysctl-const series [1].
> > To slim down that series and reduce the message load on other
> > maintainers to a minimumble, submit this patch on its own.
> >
> > [0] https://lore.kernel.org/lkml/20240222160915.315255-1-aleksandr.mikhalitsyn@canonical.com/
> > [1] https://lore.kernel.org/lkml/20231204-const-sysctl-v2-2-7a5060b11447@weissschuh.net/
> > ---
> > include/linux/sysctl.h | 2 +-
> > ipc/ipc_sysctl.c | 2 +-
> > kernel/ucount.c | 2 +-
> > net/sysctl_net.c | 2 +-
> > 4 files changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
> > index ee7d33b89e9e..0a55b5aade16 100644
> > --- a/include/linux/sysctl.h
> > +++ b/include/linux/sysctl.h
> > @@ -207,7 +207,7 @@ struct ctl_table_root {
> > void (*set_ownership)(struct ctl_table_header *head,
> > struct ctl_table *table,
> > kuid_t *uid, kgid_t *gid);
> > - int (*permissions)(struct ctl_table_header *head, struct ctl_table *table);
> > + int (*permissions)(struct ctl_table_header *head, const struct ctl_table *table);
> > };
> >
> > #define register_sysctl(path, table) \
> > diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c
> > index 8c62e443f78b..b087787f608f 100644
> > --- a/ipc/ipc_sysctl.c
> > +++ b/ipc/ipc_sysctl.c
> > @@ -190,7 +190,7 @@ static int set_is_seen(struct ctl_table_set *set)
> > return ¤t->nsproxy->ipc_ns->ipc_set == set;
> > }
> >
> > -static int ipc_permissions(struct ctl_table_header *head, struct ctl_table *table)
> > +static int ipc_permissions(struct ctl_table_header *head, const struct ctl_table *table)
> > {
> > int mode = table->mode;
> >
> > diff --git a/kernel/ucount.c b/kernel/ucount.c
> > index 4aa6166cb856..90300840256b 100644
> > --- a/kernel/ucount.c
> > +++ b/kernel/ucount.c
> > @@ -38,7 +38,7 @@ static int set_is_seen(struct ctl_table_set *set)
> > }
> >
> > static int set_permissions(struct ctl_table_header *head,
> > - struct ctl_table *table)
> > + const struct ctl_table *table)
> > {
> > struct user_namespace *user_ns =
> > container_of(head->set, struct user_namespace, set);
> > diff --git a/net/sysctl_net.c b/net/sysctl_net.c
> > index 051ed5f6fc93..ba9a49de9600 100644
> > --- a/net/sysctl_net.c
> > +++ b/net/sysctl_net.c
> > @@ -40,7 +40,7 @@ static int is_seen(struct ctl_table_set *set)
> >
> > /* Return standard mode bits for table entry. */
> > static int net_ctl_permissions(struct ctl_table_header *head,
> > - struct ctl_table *table)
> > + const struct ctl_table *table)
> > {
> > struct net *net = container_of(head->set, struct net, sysctls);
> >
> >
> > ---
> > base-commit: ffd2cb6b718e189e7e2d5d0c19c25611f92e061a
> > change-id: 20231226-sysctl-const-permissions-d7cfd02a7637
> >
> > Best regards,
> > --
> > Thomas Weißschuh <linux@...ssschuh.net>
> >
>
> --
>
> Joel Granados
Powered by blists - more mailing lists