| Message ID | 20241004155320.16629-1-stephen.smalley.work@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Paul Moore |
| Headers | show |
| Series | selinux: Deprecate /sys/fs/selinux/user | expand |
On Fri, Oct 4, 2024 at 11:53 AM Stephen Smalley <stephen.smalley.work@gmail.com> wrote: > > The only known user of this interface was libselinux and its > internal usage of this interface for get_ordered_context_list(3) > was removed in Feb 2020, with a deprecation warning added to > security_compute_user(3) at the same time. Add a deprecation > warning to the kernel and schedule it for final removal in 2025. > > Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> > --- > Documentation/ABI/obsolete/sysfs-selinux-user | 12 ++++++++++++ > security/selinux/selinuxfs.c | 4 ++++ > 2 files changed, 16 insertions(+) > create mode 100644 Documentation/ABI/obsolete/sysfs-selinux-user > > diff --git a/Documentation/ABI/obsolete/sysfs-selinux-user b/Documentation/ABI/obsolete/sysfs-selinux-user > new file mode 100644 > index 000000000000..8ab7557f283f > --- /dev/null > +++ b/Documentation/ABI/obsolete/sysfs-selinux-user > @@ -0,0 +1,12 @@ > +What: /sys/fs/selinux/user > +Date: April 2005 (predates git) > +KernelVersion: 2.6.12-rc2 (predates git) > +Contact: selinux@vger.kernel.org > +Description: > + > + The selinuxfs "user" node allows userspace to request a list > + of security contexts that can be reached for a given SELinux > + user from a given starting context. This was used by libselinux > + when various login-style programs requested contexts for > + users, but libselinux stopped using it in 2020. > + Kernel support will be removed no sooner than Dec 2025. > diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c > index e172f182b65c..8117d8f6ac2d 100644 > --- a/security/selinux/selinuxfs.c > +++ b/security/selinux/selinuxfs.c > @@ -1069,6 +1069,10 @@ static ssize_t sel_write_user(struct file *file, char *buf, size_t size) > int rc; > u32 i, len, nsids; > > + pr_warn_once("SELinux: %s (%d) wrote to /sys/fs/selinux/user! This " > + "will not be supported in the future; please update your " > + "userspace.\n", current->comm, current->pid); Since this could be triggered by multiple different applications, it is worth using pr_warn() so users have a better list of what applications are causing this notice? I understand that there is a risk of log spam, but considering the limited use of this API it seems like this is a reasonable risk? > length = avc_has_perm(current_sid(), SECINITSID_SECURITY, > SECCLASS_SECURITY, SECURITY__COMPUTE_USER, > NULL); > -- > 2.40.1
On Fri, Oct 4, 2024 at 12:57 PM Paul Moore <paul@paul-moore.com> wrote: > > On Fri, Oct 4, 2024 at 11:53 AM Stephen Smalley > <stephen.smalley.work@gmail.com> wrote: > > > > The only known user of this interface was libselinux and its > > internal usage of this interface for get_ordered_context_list(3) > > was removed in Feb 2020, with a deprecation warning added to > > security_compute_user(3) at the same time. Add a deprecation > > warning to the kernel and schedule it for final removal in 2025. > > > > Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> > > --- > > Documentation/ABI/obsolete/sysfs-selinux-user | 12 ++++++++++++ > > security/selinux/selinuxfs.c | 4 ++++ > > 2 files changed, 16 insertions(+) > > create mode 100644 Documentation/ABI/obsolete/sysfs-selinux-user > > > > diff --git a/Documentation/ABI/obsolete/sysfs-selinux-user b/Documentation/ABI/obsolete/sysfs-selinux-user > > new file mode 100644 > > index 000000000000..8ab7557f283f > > --- /dev/null > > +++ b/Documentation/ABI/obsolete/sysfs-selinux-user > > @@ -0,0 +1,12 @@ > > +What: /sys/fs/selinux/user > > +Date: April 2005 (predates git) > > +KernelVersion: 2.6.12-rc2 (predates git) > > +Contact: selinux@vger.kernel.org > > +Description: > > + > > + The selinuxfs "user" node allows userspace to request a list > > + of security contexts that can be reached for a given SELinux > > + user from a given starting context. This was used by libselinux > > + when various login-style programs requested contexts for > > + users, but libselinux stopped using it in 2020. > > + Kernel support will be removed no sooner than Dec 2025. > > diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c > > index e172f182b65c..8117d8f6ac2d 100644 > > --- a/security/selinux/selinuxfs.c > > +++ b/security/selinux/selinuxfs.c > > @@ -1069,6 +1069,10 @@ static ssize_t sel_write_user(struct file *file, char *buf, size_t size) > > int rc; > > u32 i, len, nsids; > > > > + pr_warn_once("SELinux: %s (%d) wrote to /sys/fs/selinux/user! This " > > + "will not be supported in the future; please update your " > > + "userspace.\n", current->comm, current->pid); > > Since this could be triggered by multiple different applications, it > is worth using pr_warn() so users have a better list of what > applications are causing this notice? I understand that there is a > risk of log spam, but considering the limited use of this API it seems > like this is a reasonable risk? I'd be fine switching it to pr_warn(), but in reality, I think the only direct user was libselinux, so that's the component that actually needs to be updated if it triggers.
diff --git a/Documentation/ABI/obsolete/sysfs-selinux-user b/Documentation/ABI/obsolete/sysfs-selinux-user new file mode 100644 index 000000000000..8ab7557f283f --- /dev/null +++ b/Documentation/ABI/obsolete/sysfs-selinux-user @@ -0,0 +1,12 @@ +What: /sys/fs/selinux/user +Date: April 2005 (predates git) +KernelVersion: 2.6.12-rc2 (predates git) +Contact: selinux@vger.kernel.org +Description: + + The selinuxfs "user" node allows userspace to request a list + of security contexts that can be reached for a given SELinux + user from a given starting context. This was used by libselinux + when various login-style programs requested contexts for + users, but libselinux stopped using it in 2020. + Kernel support will be removed no sooner than Dec 2025. diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index e172f182b65c..8117d8f6ac2d 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -1069,6 +1069,10 @@ static ssize_t sel_write_user(struct file *file, char *buf, size_t size) int rc; u32 i, len, nsids; + pr_warn_once("SELinux: %s (%d) wrote to /sys/fs/selinux/user! This " + "will not be supported in the future; please update your " + "userspace.\n", current->comm, current->pid); + length = avc_has_perm(current_sid(), SECINITSID_SECURITY, SECCLASS_SECURITY, SECURITY__COMPUTE_USER, NULL);
The only known user of this interface was libselinux and its internal usage of this interface for get_ordered_context_list(3) was removed in Feb 2020, with a deprecation warning added to security_compute_user(3) at the same time. Add a deprecation warning to the kernel and schedule it for final removal in 2025. Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> --- Documentation/ABI/obsolete/sysfs-selinux-user | 12 ++++++++++++ security/selinux/selinuxfs.c | 4 ++++ 2 files changed, 16 insertions(+) create mode 100644 Documentation/ABI/obsolete/sysfs-selinux-user