linux/security/smack, branch v4.3

Smack - Fix build error with bringup unconfigured

2015-08-13T01:10:01Z

The changes for mounting binary filesystems was allied improperly, with the list of tokens being in an ifdef that it shouldn't have been. Fix that, and a couple style issues that were bothering me. Reported-by: Jim Davis Signed-off-by: Casey Schaufler

Kernel threads excluded from smack checks

2015-08-10T22:15:50Z

Adds an ignore case for kernel tasks, so that they can access all resources. Since kernel worker threads are spawned with floor label, they are severely restricted by Smack policy. It is not an issue without onlycap, as these processes also run with root, so CAP_MAC_OVERRIDE kicks in. But with onlycap turned on, there is no way to change the label for these processes. Signed-off-by: Roman Kubiak Acked-by: Casey Schaufler

Smack: Three symbols that should be static

2015-07-31T19:12:17Z

The kbuild test robot reported a couple of these, and the third showed up by inspection. Making the symbols static is proper. Reported-by: Fengguang Wu Signed-off-by: Casey Schaufler

Smack: IPv6 host labeling

2015-07-28T13:35:21Z

IPv6 appears to be (finally) coming of age with the influx of autonomous devices. In support of this, add the ability to associate a Smack label with IPv6 addresses. This patch also cleans up some of the conditional compilation associated with the introduction of secmark processing. It's now more obvious which bit of code goes with which feature. Signed-off-by: Casey Schaufler

sysfs: fix simple_return.cocci warnings

2015-07-22T19:31:40Z

security/smack/smackfs.c:2251:1-4: WARNING: end returns can be simpified and declaration on line 2250 can be dropped Simplify a trivial if-return sequence. Possibly combine with a preceding function call. Generated by: scripts/coccinelle/misc/simple_return.cocci Signed-off-by: Fengguang Wu Acked-by: Serge Hallyn Acked-by: Casey Schaufler

smack: allow mount opts setting over filesystems with binary mount data

2015-07-22T19:31:28Z

Add support for setting smack mount labels(using smackfsdef, smackfsroot, smackfshat, smackfsfloor, smackfstransmute) for filesystems with binary mount data like NFS. To achieve this, implement sb_parse_opts_str and sb_set_mnt_opts security operations in smack LSM similar to SELinux. Signed-off-by: Vivek Trivedi Signed-off-by: Amit Sahrawat Acked-by: Casey Schaufler

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2015-07-03T22:20:57Z

Pull user namespace updates from Eric Biederman: "Long ago and far away when user namespaces where young it was realized that allowing fresh mounts of proc and sysfs with only user namespace permissions could violate the basic rule that only root gets to decide if proc or sysfs should be mounted at all. Some hacks were put in place to reduce the worst of the damage could be done, and the common sense rule was adopted that fresh mounts of proc and sysfs should allow no more than bind mounts of proc and sysfs. Unfortunately that rule has not been fully enforced. There are two kinds of gaps in that enforcement. Only filesystems mounted on empty directories of proc and sysfs should be ignored but the test for empty directories was insufficient. So in my tree directories on proc, sysctl and sysfs that will always be empty are created specially. Every other technique is imperfect as an ordinary directory can have entries added even after a readdir returns and shows that the directory is empty. Special creation of directories for mount points makes the code in the kernel a smidge clearer about it's purpose. I asked container developers from the various container projects to help test this and no holes were found in the set of mount points on proc and sysfs that are created specially. This set of changes also starts enforcing the mount flags of fresh mounts of proc and sysfs are consistent with the existing mount of proc and sysfs. I expected this to be the boring part of the work but unfortunately unprivileged userspace winds up mounting fresh copies of proc and sysfs with noexec and nosuid clear when root set those flags on the previous mount of proc and sysfs. So for now only the atime, read-only and nodev attributes which userspace happens to keep consistent are enforced. Dealing with the noexec and nosuid attributes remains for another time. This set of changes also addresses an issue with how open file descriptors from /proc//ns/* are displayed. Recently readlink of /proc//fd has been triggering a WARN_ON that has not been meaningful since it was added (as all of the code in the kernel was converted) and is not now actively wrong. There is also a short list of issues that have not been fixed yet that I will mention briefly. It is possible to rename a directory from below to above a bind mount. At which point any directory pointers below the renamed directory can be walked up to the root directory of the filesystem. With user namespaces enabled a bind mount of the bind mount can be created allowing the user to pick a directory whose children they can rename to outside of the bind mount. This is challenging to fix and doubly so because all obvious solutions must touch code that is in the performance part of pathname resolution. As mentioned above there is also a question of how to ensure that developers by accident or with purpose do not introduce exectuable files on sysfs and proc and in doing so introduce security regressions in the current userspace that will not be immediately obvious and as such are likely to require breaking userspace in painful ways once they are recognized" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: vfs: Remove incorrect debugging WARN in prepend_path mnt: Update fs_fully_visible to test for permanently empty directories sysfs: Create mountpoints with sysfs_create_mount_point sysfs: Add support for permanently empty directories to serve as mount points. kernfs: Add support for always empty directories. proc: Allow creating permanently empty directories that serve as mount points sysctl: Allow creating permanently empty directories that serve as mountpoints. fs: Add helper functions for permanently empty directories. vfs: Ignore unlocked mounts in fs_fully_visible mnt: Modify fs_fully_visible to deal with locked ro nodev and atime mnt: Refactor the logic for mounting sysfs and proc in a user namespace

sysfs: Create mountpoints with sysfs_create_mount_point

2015-07-01T15:36:47Z

This allows for better documentation in the code and it allows for a simpler and fully correct version of fs_fully_visible to be written. The mount points converted and their filesystems are: /sys/hypervisor/s390/ s390_hypfs /sys/kernel/config/ configfs /sys/kernel/debug/ debugfs /sys/firmware/efi/efivars/ efivarfs /sys/fs/fuse/connections/ fusectl /sys/fs/pstore/ pstore /sys/kernel/tracing/ tracefs /sys/fs/cgroup/ cgroup /sys/kernel/security/ securityfs /sys/fs/selinux/ selinuxfs /sys/fs/smackfs/ smackfs Cc: stable@vger.kernel.org Acked-by: Greg Kroah-Hartman Signed-off-by: "Eric W. Biederman"

Smack: freeing an error pointer in smk_write_revoke_subj()

2015-06-12T18:59:11Z

This code used to rely on the fact that kfree(NULL) was a no-op, but then we changed smk_parse_smack() to return error pointers on failure instead of NULL. Calling kfree() on an error pointer will oops. I have re-arranged things a bit so that we only free things if they have been allocated. Fixes: e774ad683f42 ('smack: pass error code through pointers') Signed-off-by: Dan Carpenter

Smack: allow multiple labels in onlycap

2015-06-02T18:53:42Z

Smack onlycap allows limiting of CAP_MAC_ADMIN and CAP_MAC_OVERRIDE to processes running with the configured label. But having single privileged label is not enough in some real use cases. On a complex system like Tizen, there maybe few programs that need to configure Smack policy in run-time and running them all with a single label is not always practical. This patch extends onlycap feature for multiple labels. They are configured in the same smackfs "onlycap" interface, separated by spaces. Signed-off-by: Rafal Krypa