| Message ID | dae0dbe1a78be2ce5506b90fc4ffd12c82fa1061.1725657728.git.fahimitahera@gmail.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | landlock: Signal scoping support | expand |
On Fri, Sep 06, 2024 at 03:30:08PM -0600, Tahera Fahimi wrote: > Improving Landlock ABI version 6 to support signal scoping with > LANDLOCK_SCOPED_SIGNAL. > > Signed-off-by: Tahera Fahimi <fahimitahera@gmail.com> > --- > v3: > - update date > --- > Documentation/userspace-api/landlock.rst | 22 +++++++++++++++------- > 1 file changed, 15 insertions(+), 7 deletions(-) > > diff --git a/Documentation/userspace-api/landlock.rst b/Documentation/userspace-api/landlock.rst > index c3b87755e98d..c694e9fe36fc 100644 > --- a/Documentation/userspace-api/landlock.rst > +++ b/Documentation/userspace-api/landlock.rst > @@ -82,7 +82,8 @@ to be explicit about the denied-by-default access rights. > LANDLOCK_ACCESS_NET_BIND_TCP | > LANDLOCK_ACCESS_NET_CONNECT_TCP, > .scoped = > - LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET, > + LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET | > + LANDLOCK_SCOPED_SIGNAL, > }; > > Because we may not know on which kernel version an application will be > @@ -123,7 +124,8 @@ version, and only use the available subset of access rights: > ruleset_attr.handled_access_fs &= ~LANDLOCK_ACCESS_FS_IOCTL_DEV; > case 5: > /* Removes LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET for ABI < 6 */ > - ruleset_attr.scoped &= ~LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET; > + ruleset_attr.scoped &= ~(LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET | > + LANDLOCK_SCOPED_SIGNAL); > } > > This enables to create an inclusive ruleset that will contain our rules. > @@ -320,11 +322,15 @@ explicitly scoped for a set of actions by specifying it on a ruleset. > For example, if a sandboxed process should not be able to > :manpage:`connect(2)` to a non-sandboxed process through abstract > :manpage:`unix(7)` sockets, we can specify such restriction with > -``LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET``. > +``LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET``. Moreover, if a sandboxed > +process should not be able to send a signal to a non-sandboxed process, > +we can specify this restriction with ``LANDLOCK_SCOPED_SIGNAL``. > > A sandboxed process can connect to a non-sandboxed process when its > domain is not scoped. If a process's domain is scoped, it can only > connect to sockets created by processes in the same scoped domain. > +Moreover, If a process is scoped to send signal to a non-scoped process, > +it can only send signals to processes in the same scoped domain. > > A connected datagram socket behaves like a stream socket when its domain > is scoped, meaning if the domain is scoped after the socket is connected > @@ -575,12 +581,14 @@ earlier ABI. > Starting with the Landlock ABI version 5, it is possible to restrict the use of > :manpage:`ioctl(2)` using the new ``LANDLOCK_ACCESS_FS_IOCTL_DEV`` right. > > -Abstract UNIX sockets Restriction (ABI < 6) > --------------------------------------------- > +Abstract Unix sockets and Signal Restriction (ABI < 6) > +------------------------------------------------------- I created a dedicated section instead of merging both. > > +<<<<<<< current I fixed that. > With ABI version 6, it is possible to restrict connection to an abstract > -Unix socket through ``LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET``, thanks to > -the ``scoped`` ruleset attribute. > +:manpage:`unix(7)` socket through > +``LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET`` and sending signal through > +``LANDLOCK_SCOPED_SIGNAL``, thanks to the ``scoped`` ruleset attribute. I cleaned up this fix that should be part of the other series. > > .. _kernel_support: > > -- > 2.34.1 > >
diff --git a/Documentation/userspace-api/landlock.rst b/Documentation/userspace-api/landlock.rst index c3b87755e98d..c694e9fe36fc 100644 --- a/Documentation/userspace-api/landlock.rst +++ b/Documentation/userspace-api/landlock.rst @@ -82,7 +82,8 @@ to be explicit about the denied-by-default access rights. LANDLOCK_ACCESS_NET_BIND_TCP | LANDLOCK_ACCESS_NET_CONNECT_TCP, .scoped = - LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET, + LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET | + LANDLOCK_SCOPED_SIGNAL, }; Because we may not know on which kernel version an application will be @@ -123,7 +124,8 @@ version, and only use the available subset of access rights: ruleset_attr.handled_access_fs &= ~LANDLOCK_ACCESS_FS_IOCTL_DEV; case 5: /* Removes LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET for ABI < 6 */ - ruleset_attr.scoped &= ~LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET; + ruleset_attr.scoped &= ~(LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET | + LANDLOCK_SCOPED_SIGNAL); } This enables to create an inclusive ruleset that will contain our rules. @@ -320,11 +322,15 @@ explicitly scoped for a set of actions by specifying it on a ruleset. For example, if a sandboxed process should not be able to :manpage:`connect(2)` to a non-sandboxed process through abstract :manpage:`unix(7)` sockets, we can specify such restriction with -``LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET``. +``LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET``. Moreover, if a sandboxed +process should not be able to send a signal to a non-sandboxed process, +we can specify this restriction with ``LANDLOCK_SCOPED_SIGNAL``. A sandboxed process can connect to a non-sandboxed process when its domain is not scoped. If a process's domain is scoped, it can only connect to sockets created by processes in the same scoped domain. +Moreover, If a process is scoped to send signal to a non-scoped process, +it can only send signals to processes in the same scoped domain. A connected datagram socket behaves like a stream socket when its domain is scoped, meaning if the domain is scoped after the socket is connected @@ -575,12 +581,14 @@ earlier ABI. Starting with the Landlock ABI version 5, it is possible to restrict the use of :manpage:`ioctl(2)` using the new ``LANDLOCK_ACCESS_FS_IOCTL_DEV`` right. -Abstract UNIX sockets Restriction (ABI < 6) --------------------------------------------- +Abstract Unix sockets and Signal Restriction (ABI < 6) +------------------------------------------------------- +<<<<<<< current With ABI version 6, it is possible to restrict connection to an abstract -Unix socket through ``LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET``, thanks to -the ``scoped`` ruleset attribute. +:manpage:`unix(7)` socket through +``LANDLOCK_SCOPED_ABSTRACT_UNIX_SOCKET`` and sending signal through +``LANDLOCK_SCOPED_SIGNAL``, thanks to the ``scoped`` ruleset attribute. .. _kernel_support:
Improving Landlock ABI version 6 to support signal scoping with LANDLOCK_SCOPED_SIGNAL. Signed-off-by: Tahera Fahimi <fahimitahera@gmail.com> --- v3: - update date --- Documentation/userspace-api/landlock.rst | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-)