talos-op-linux/security/smack, branch v4.8.6

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2016-07-30T00:38:46+00:00

Pull security subsystem updates from James Morris: "Highlights: - TPM core and driver updates/fixes - IPv6 security labeling (CALIPSO) - Lots of Apparmor fixes - Seccomp: remove 2-phase API, close hole where ptrace can change syscall #" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (156 commits) apparmor: fix SECURITY_APPARMOR_HASH_DEFAULT parameter handling tpm: Add TPM 2.0 support to the Nuvoton i2c driver (NPCT6xx family) tpm: Factor out common startup code tpm: use devm_add_action_or_reset tpm2_i2c_nuvoton: add irq validity check tpm: read burstcount from TPM_STS in one 32-bit transaction tpm: fix byte-order for the value read by tpm2_get_tpm_pt tpm_tis_core: convert max timeouts from msec to jiffies apparmor: fix arg_size computation for when setprocattr is null terminated apparmor: fix oops, validate buffer size in apparmor_setprocattr() apparmor: do not expose kernel stack apparmor: fix module parameters can be changed after policy is locked apparmor: fix oops in profile_unpack() when policy_db is not present apparmor: don't check for vmalloc_addr if kvzalloc() failed apparmor: add missing id bounds check on dfa verification apparmor: allow SYS_CAP_RESOURCE to be sufficient to prlimit another task apparmor: use list_next_entry instead of list_entry_next apparmor: fix refcount race when finding a child profile apparmor: fix ref count leak when profile sha1 hash is read apparmor: check that xindex is in trans_table bounds ...

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

2016-07-29T22:54:19+00:00

Pull userns vfs updates from Eric Biederman: "This tree contains some very long awaited work on generalizing the user namespace support for mounting filesystems to include filesystems with a backing store. The real world target is fuse but the goal is to update the vfs to allow any filesystem to be supported. This patchset is based on a lot of code review and testing to approach that goal. While looking at what is needed to support the fuse filesystem it became clear that there were things like xattrs for security modules that needed special treatment. That the resolution of those concerns would not be fuse specific. That sorting out these general issues made most sense at the generic level, where the right people could be drawn into the conversation, and the issues could be solved for everyone. At a high level what this patchset does a couple of simple things: - Add a user namespace owner (s_user_ns) to struct super_block. - Teach the vfs to handle filesystem uids and gids not mapping into to kuids and kgids and being reported as INVALID_UID and INVALID_GID in vfs data structures. By assigning a user namespace owner filesystems that are mounted with only user namespace privilege can be detected. This allows security modules and the like to know which mounts may not be trusted. This also allows the set of uids and gids that are communicated to the filesystem to be capped at the set of kuids and kgids that are in the owning user namespace of the filesystem. One of the crazier corner casees this handles is the case of inodes whose i_uid or i_gid are not mapped into the vfs. Most of the code simply doesn't care but it is easy to confuse the inode writeback path so no operation that could cause an inode write-back is permitted for such inodes (aka only reads are allowed). This set of changes starts out by cleaning up the code paths involved in user namespace permirted mounts. Then when things are clean enough adds code that cleanly sets s_user_ns. Then additional restrictions are added that are possible now that the filesystem superblock contains owner information. These changes should not affect anyone in practice, but there are some parts of these restrictions that are changes in behavior. - Andy's restriction on suid executables that does not honor the suid bit when the path is from another mount namespace (think /proc/[pid]/fd/) or when the filesystem was mounted by a less privileged user. - The replacement of the user namespace implicit setting of MNT_NODEV with implicitly setting SB_I_NODEV on the filesystem superblock instead. Using SB_I_NODEV is a stronger form that happens to make this state user invisible. The user visibility can be managed but it caused problems when it was introduced from applications reasonably expecting mount flags to be what they were set to. There is a little bit of work remaining before it is safe to support mounting filesystems with backing store in user namespaces, beyond what is in this set of changes. - Verifying the mounter has permission to read/write the block device during mount. - Teaching the integrity modules IMA and EVM to handle filesystems mounted with only user namespace root and to reduce trust in their security xattrs accordingly. - Capturing the mounters credentials and using that for permission checks in d_automount and the like. (Given that overlayfs already does this, and we need the work in d_automount it make sense to generalize this case). Furthermore there are a few changes that are on the wishlist: - Get all filesystems supporting posix acls using the generic posix acls so that posix_acl_fix_xattr_from_user and posix_acl_fix_xattr_to_user may be removed. [Maintainability] - Reducing the permission checks in places such as remount to allow the superblock owner to perform them. - Allowing the superblock owner to chown files with unmapped uids and gids to something that is mapped so the files may be treated normally. I am not considering even obvious relaxations of permission checks until it is clear there are no more corner cases that need to be locked down and handled generically. Many thanks to Seth Forshee who kept this code alive, and putting up with me rewriting substantial portions of what he did to handle more corner cases, and for his diligent testing and reviewing of my changes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (30 commits) fs: Call d_automount with the filesystems creds fs: Update i_[ug]id_(read|write) to translate relative to s_user_ns evm: Translate user/group ids relative to s_user_ns when computing HMAC dquot: For now explicitly don't support filesystems outside of init_user_ns quota: Handle quota data stored in s_user_ns in quota_setxquota quota: Ensure qids map to the filesystem vfs: Don't create inodes with a uid or gid unknown to the vfs vfs: Don't modify inodes with a uid or gid unknown to the vfs cred: Reject inodes with invalid ids in set_create_file_as() fs: Check for invalid i_uid in may_follow_link() vfs: Verify acls are valid within superblock's s_user_ns. userns: Handle -1 in k[ug]id_has_mapping when !CONFIG_USER_NS fs: Refuse uid/gid changes which don't map into s_user_ns selinux: Add support for unprivileged mounts from user namespaces Smack: Handle labels consistently in untrusted mounts Smack: Add support for unprivileged mounts from user namespaces fs: Treat foreign mounts as nosuid fs: Limit file caps to the user namespace of the super block userns: Remove the now unnecessary FS_USERNS_DEV_MOUNT flag userns: Remove implicit MNT_NODEV fragility. ...

Merge branch 'smack-for-4.8' of https://github.com/cschaufler/smack-next into next

2016-07-08T00:41:15+00:00

Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux into next

2016-07-07T00:15:34+00:00

netlabel: Pass a family parameter to netlbl_skbuff_err().

2016-06-27T19:06:16+00:00

This makes it possible to route the error to the appropriate labelling engine. CALIPSO is far less verbose than CIPSO when encountering a bogus packet, so there is no need for a CALIPSO error handler. Signed-off-by: Huw Davies Signed-off-by: Paul Moore

Smack: Handle labels consistently in untrusted mounts

2016-06-24T16:02:22+00:00

The SMACK64, SMACK64EXEC, and SMACK64MMAP labels are all handled differently in untrusted mounts. This is confusing and potentically problematic. Change this to handle them all the same way that SMACK64 is currently handled; that is, read the label from disk and check it at use time. For SMACK64 and SMACK64MMAP access is denied if the label does not match smk_root. To be consistent with suid, a SMACK64EXEC label which does not match smk_root will still allow execution of the file but will not run with the label supplied in the xattr. Signed-off-by: Seth Forshee Acked-by: Casey Schaufler Signed-off-by: Eric W. Biederman

Smack: Add support for unprivileged mounts from user namespaces

2016-06-24T15:40:42+00:00

Security labels from unprivileged mounts cannot be trusted. Ideally for these mounts we would assign the objects in the filesystem the same label as the inode for the backing device passed to mount. Unfortunately it's currently impossible to determine which inode this is from the LSM mount hooks, so we settle for the label of the process doing the mount. This label is assigned to s_root, and also to smk_default to ensure that new inodes receive this label. The transmute property is also set on s_root to make this behavior more explicit, even though it is technically not necessary. If a filesystem has existing security labels, access to inodes is permitted if the label is the same as smk_root, otherwise access is denied. The SMACK64EXEC xattr is completely ignored. Explicit setting of security labels continues to require CAP_MAC_ADMIN in init_user_ns. Altogether, this ensures that filesystem objects are not accessible to subjects which cannot already access the backing store, that MAC is not violated for any objects in the fileystem which are already labeled, and that a user cannot use an unprivileged mount to gain elevated MAC privileges. sysfs, tmpfs, and ramfs are already mountable from user namespaces and support security labels. We can't rule out the possibility that these filesystems may already be used in mounts from user namespaces with security lables set from the init namespace, so failing to trust lables in these filesystems may introduce regressions. It is safe to trust labels from these filesystems, since the unprivileged user does not control the backing store and thus cannot supply security labels, so an explicit exception is made to trust labels from these filesystems. Signed-off-by: Seth Forshee Acked-by: Casey Schaufler Signed-off-by: Eric W. Biederman

vfs: make the string hashes salt the hash

2016-06-11T03:21:46+00:00

We always mixed in the parent pointer into the dentry name hash, but we did it late at lookup time. It turns out that we can simplify that lookup-time action by salting the hash with the parent pointer early instead of late. A few other users of our string hashes also wanted to mix in their own pointers into the hash, and those are updated to use the same mechanism. Hash users that don't have any particular initial salt can just use the NULL pointer as a no-salt. Cc: Vegard Nossum Cc: George Spelvin Cc: Al Viro Signed-off-by: Linus Torvalds

Smack: ignore null signal in smack_task_kill

2016-06-08T20:52:31+00:00

Kill with signal number 0 is commonly used for checking PID existence. Smack treated such cases like any other kills, although no signal is actually delivered when sig == 0. Checking permissions when sig == 0 didn't prevent an unprivileged caller from learning whether PID exists or not. When it existed, kernel returned EPERM, when it didn't - ESRCH. The only effect of policy check in such case is noise in audit logs. This change lets Smack silently ignore kill() invocations with sig == 0. Signed-off-by: Rafal Krypa Acked-by: Casey Schaufler

switch ->setxattr() to passing dentry and inode separately

2016-05-28T00:09:16+00:00

smack ->d_instantiate() uses ->setxattr(), so to be able to call it before we'd hashed the new dentry and attached it to inode, we need ->setxattr() instances getting the inode as an explicit argument rather than obtaining it from dentry. Similar change for ->getxattr() had been done in commit ce23e64. Unlike ->getxattr() (which is used by both selinux and smack instances of ->d_instantiate()) ->setxattr() is used only by smack one and unfortunately it got missed back then. Reported-by: Seung-Woo Kim Tested-by: Casey Schaufler Signed-off-by: Al Viro