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2017-02-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2017-02-10Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/selinux ↵James Morris
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2017-02-08selinux: fix off-by-one in setprocattrStephen Smalley
SELinux tries to support setting/clearing of /proc/pid/attr attributes from the shell by ignoring terminating newlines and treating an attribute value that begins with a NUL or newline as an attempt to clear the attribute. However, the test for clearing attributes has always been wrong; it has an off-by-one error, and this could further lead to reading past the end of the allocated buffer since commit bb646cdb12e75d82258c2f2e7746d5952d3e321a ("proc_pid_attr_write(): switch to memdup_user()"). Fix the off-by-one error. Even with this fix, setting and clearing /proc/pid/attr attributes from the shell is not straightforward since the interface does not support multiple write() calls (so shells that write the value and newline separately will set and then immediately clear the attribute, requiring use of echo -n to set the attribute), whereas trying to use echo -n "" to clear the attribute causes the shell to skip the write() call altogether since POSIX says that a zero-length write causes no side effects. Thus, one must use echo -n to set and echo without -n to clear, as in the following example: $ echo -n unconfined_u:object_r:user_home_t:s0 > /proc/$$/attr/fscreate $ cat /proc/$$/attr/fscreate unconfined_u:object_r:user_home_t:s0 $ echo "" > /proc/$$/attr/fscreate $ cat /proc/$$/attr/fscreate Note the use of /proc/$$ rather than /proc/self, as otherwise the cat command will read its own attribute value, not that of the shell. There are no users of this facility to my knowledge; possibly we should just get rid of it. UPDATE: Upon further investigation it appears that a local process with the process:setfscreate permission can cause a kernel panic as a result of this bug. This patch fixes CVE-2017-2618. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> [PM: added the update about CVE-2017-2618 to the commit description] Cc: stable@vger.kernel.org # 3.5: d6ea83ec6864e Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-02-08Merge branch 'stable-4.10' of git://git.infradead.org/users/pcmoore/selinux ↵James Morris
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2017-02-07selinux: allow changing labels for cgroupfsAntonio Murdaca
This patch allows changing labels for cgroup mounts. Previously, running chcon on cgroupfs would throw an "Operation not supported". This patch specifically whitelist cgroupfs. The patch could also allow containers to write only to the systemd cgroup for instance, while the other cgroups are kept with cgroup_t label. Signed-off-by: Antonio Murdaca <runcom@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-02-07selinux: fix off-by-one in setprocattrStephen Smalley
SELinux tries to support setting/clearing of /proc/pid/attr attributes from the shell by ignoring terminating newlines and treating an attribute value that begins with a NUL or newline as an attempt to clear the attribute. However, the test for clearing attributes has always been wrong; it has an off-by-one error, and this could further lead to reading past the end of the allocated buffer since commit bb646cdb12e75d82258c2f2e7746d5952d3e321a ("proc_pid_attr_write(): switch to memdup_user()"). Fix the off-by-one error. Even with this fix, setting and clearing /proc/pid/attr attributes from the shell is not straightforward since the interface does not support multiple write() calls (so shells that write the value and newline separately will set and then immediately clear the attribute, requiring use of echo -n to set the attribute), whereas trying to use echo -n "" to clear the attribute causes the shell to skip the write() call altogether since POSIX says that a zero-length write causes no side effects. Thus, one must use echo -n to set and echo without -n to clear, as in the following example: $ echo -n unconfined_u:object_r:user_home_t:s0 > /proc/$$/attr/fscreate $ cat /proc/$$/attr/fscreate unconfined_u:object_r:user_home_t:s0 $ echo "" > /proc/$$/attr/fscreate $ cat /proc/$$/attr/fscreate Note the use of /proc/$$ rather than /proc/self, as otherwise the cat command will read its own attribute value, not that of the shell. There are no users of this facility to my knowledge; possibly we should just get rid of it. UPDATE: Upon further investigation it appears that a local process with the process:setfscreate permission can cause a kernel panic as a result of this bug. This patch fixes CVE-2017-2618. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> [PM: added the update about CVE-2017-2618 to the commit description] Cc: stable@vger.kernel.org # 3.5: d6ea83ec6864e Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-24Introduce a sysctl that modifies the value of PROT_SOCK.Krister Johansen
Add net.ipv4.ip_unprivileged_port_start, which is a per namespace sysctl that denotes the first unprivileged inet port in the namespace. To disable all privileged ports set this to zero. It also checks for overlap with the local port range. The privileged and local range may not overlap. The use case for this change is to allow containerized processes to bind to priviliged ports, but prevent them from ever being allowed to modify their container's network configuration. The latter is accomplished by ensuring that the network namespace is not a child of the user namespace. This modification was needed to allow the container manager to disable a namespace's priviliged port restrictions without exposing control of the network namespace to processes in the user namespace. Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-24exec: Remove LSM_UNSAFE_PTRACE_CAPEric W. Biederman
With previous changes every location that tests for LSM_UNSAFE_PTRACE_CAP also tests for LSM_UNSAFE_PTRACE making the LSM_UNSAFE_PTRACE_CAP redundant, so remove it. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-01-19LSM: Add /sys/kernel/security/lsmCasey Schaufler
I am still tired of having to find indirect ways to determine what security modules are active on a system. I have added /sys/kernel/security/lsm, which contains a comma separated list of the active security modules. No more groping around in /proc/filesystems or other clever hacks. Unchanged from previous versions except for being updated to the latest security next branch. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: John Johansen <john.johansen@canonical.com> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-01-12security,selinux,smack: kill security_task_wait hookStephen Smalley
As reported by yangshukui, a permission denial from security_task_wait() can lead to a soft lockup in zap_pid_ns_processes() since it only expects sys_wait4() to return 0 or -ECHILD. Further, security_task_wait() can in general lead to zombies; in the absence of some way to automatically reparent a child process upon a denial, the hook is not useful. Remove the security hook and its implementations in SELinux and Smack. Smack already removed its check from its hook. Reported-by: yangshukui <yangshukui@huawei.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-12selinux: drop unused socket security classesStephen Smalley
Several of the extended socket classes introduced by commit da69a5306ab92e07 ("selinux: support distinctions among all network address families") are never used because sockets can never be created with the associated address family. Remove these unused socket security classes. The removed classes are bridge_socket for PF_BRIDGE, ib_socket for PF_IB, and mpls_socket for PF_MPLS. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-09proc,security: move restriction on writing /proc/pid/attr nodes to procStephen Smalley
Processes can only alter their own security attributes via /proc/pid/attr nodes. This is presently enforced by each individual security module and is also imposed by the Linux credentials implementation, which only allows a task to alter its own credentials. Move the check enforcing this restriction from the individual security modules to proc_pid_attr_write() before calling the security hook, and drop the unnecessary task argument to the security hook since it can only ever be the current task. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-09selinux: clean up cred usage and simplifyStephen Smalley
SELinux was sometimes using the task "objective" credentials when it could/should use the "subjective" credentials. This was sometimes hidden by the fact that we were unnecessarily passing around pointers to the current task, making it appear as if the task could be something other than current, so eliminate all such passing of current. Inline various permission checking helper functions that can be reduced to a single avc_has_perm() call. Since the credentials infrastructure only allows a task to alter its own credentials, we can always assume that current must be the same as the target task in selinux_setprocattr after the check. We likely should move this check from selinux_setprocattr() to proc_pid_attr_write() and drop the task argument to the security hook altogether; it can only serve to confuse things. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-09selinux: allow context mounts on tmpfs, ramfs, devpts within user namespacesStephen Smalley
commit aad82892af261b9903cc11c55be3ecf5f0b0b4f8 ("selinux: Add support for unprivileged mounts from user namespaces") prohibited any use of context mount options within non-init user namespaces. However, this breaks use of context mount options for tmpfs mounts within user namespaces, which are being used by Docker/runc. There is no reason to block such usage for tmpfs, ramfs or devpts. Exempt these filesystem types from this restriction. Before: sh$ userns_child_exec -p -m -U -M '0 1000 1' -G '0 1000 1' bash sh# mount -t tmpfs -o context=system_u:object_r:user_tmp_t:s0:c13 none /tmp mount: tmpfs is write-protected, mounting read-only mount: cannot mount tmpfs read-only After: sh$ userns_child_exec -p -m -U -M '0 1000 1' -G '0 1000 1' bash sh# mount -t tmpfs -o context=system_u:object_r:user_tmp_t:s0:c13 none /tmp sh# ls -Zd /tmp unconfined_u:object_r:user_tmp_t:s0:c13 /tmp Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-09selinux: handle ICMPv6 consistently with ICMPStephen Smalley
commit 79c8b348f215 ("selinux: support distinctions among all network address families") mapped datagram ICMP sockets to the new icmp_socket security class, but left ICMPv6 sockets unchanged. This change fixes that oversight to handle both kinds of sockets consistently. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-09selinux: add security in-core xattr support for tracefsYongqin Liu
Since kernel 4.1 ftrace is supported as a new separate filesystem. It gets automatically mounted by the kernel under the old path /sys/kernel/debug/tracing. Because it lives now on a separate filesystem SELinux needs to be updated to also support setting SELinux labels on tracefs inodes. This is required for compatibility in Android when moving to Linux 4.1 or newer. Signed-off-by: Yongqin Liu <yongqin.liu@linaro.org> Signed-off-by: William Roberts <william.c.roberts@intel.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-09selinux: support distinctions among all network address familiesStephen Smalley
Extend SELinux to support distinctions among all network address families implemented by the kernel by defining new socket security classes and mapping to them. Otherwise, many sockets are mapped to the generic socket class and are indistinguishable in policy. This has come up previously with regard to selectively allowing access to bluetooth sockets, and more recently with regard to selectively allowing access to AF_ALG sockets. Guido Trentalancia submitted a patch that took a similar approach to add only support for distinguishing AF_ALG sockets, but this generalizes his approach to handle all address families implemented by the kernel. Socket security classes are also added for ICMP and SCTP sockets. Socket security classes were not defined for AF_* values that are reserved but unimplemented in the kernel, e.g. AF_NETBEUI, AF_SECURITY, AF_ASH, AF_ECONET, AF_SNA, AF_WANPIPE. Backward compatibility is provided by only enabling the finer-grained socket classes if a new policy capability is set in the policy; older policies will behave as before. The legacy redhat1 policy capability that was only ever used in testing within Fedora for ptrace_child is reclaimed for this purpose; as far as I can tell, this policy capability is not enabled in any supported distro policy. Add a pair of conditional compilation guards to detect when new AF_* values are added so that we can update SELinux accordingly rather than having to belatedly update it long after new address families are introduced. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-12-14Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "Generally pretty quiet for this release. Highlights: Yama: - allow ptrace access for original parent after re-parenting TPM: - add documentation - many bugfixes & cleanups - define a generic open() method for ascii & bios measurements Integrity: - Harden against malformed xattrs SELinux: - bugfixes & cleanups Smack: - Remove unnecessary smack_known_invalid label - Do not apply star label in smack_setprocattr hook - parse mnt opts after privileges check (fixes unpriv DoS vuln)" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (56 commits) Yama: allow access for the current ptrace parent tpm: adjust return value of tpm_read_log tpm: vtpm_proxy: conditionally call tpm_chip_unregister tpm: Fix handling of missing event log tpm: Check the bios_dir entry for NULL before accessing it tpm: return -ENODEV if np is not set tpm: cleanup of printk error messages tpm: replace of_find_node_by_name() with dev of_node property tpm: redefine read_log() to handle ACPI/OF at runtime tpm: fix the missing .owner in tpm_bios_measurements_ops tpm: have event log use the tpm_chip tpm: drop tpm1_chip_register(/unregister) tpm: replace dynamically allocated bios_dir with a static array tpm: replace symbolic permission with octal for securityfs files char: tpm: fix kerneldoc tpm2_unseal_trusted name typo tpm_tis: Allow tpm_tis to be bound using DT tpm, tpm_vtpm_proxy: add kdoc comments for VTPM_PROXY_IOC_NEW_DEV tpm: Only call pm_runtime_get_sync if device has a parent tpm: define a generic open() method for ascii & bios measurements Documentation: tpm: add the Physical TPM device tree binding documentation ...
2016-11-22selinux: Convert isec->lock into a spinlockAndreas Gruenbacher
Convert isec->lock from a mutex into a spinlock. Instead of holding the lock while sleeping in inode_doinit_with_dentry, set isec->initialized to LABEL_PENDING and release the lock. Then, when the sid has been determined, re-acquire the lock. If isec->initialized is still set to LABEL_PENDING, set isec->sid; otherwise, the sid has been set by another task (LABEL_INITIALIZED) or invalidated (LABEL_INVALID) in the meantime. This fixes a deadlock on gfs2 where * one task is in inode_doinit_with_dentry -> gfs2_getxattr, holds isec->lock, and tries to acquire the inode's glock, and * another task is in do_xmote -> inode_go_inval -> selinux_inode_invalidate_secctx, holds the inode's glock, and tries to acquire isec->lock. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> [PM: minor tweaks to keep checkpatch.pl happy] Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-16posix-timers: Make them configurableNicolas Pitre
Some embedded systems have no use for them. This removes about 25KB from the kernel binary size when configured out. Corresponding syscalls are routed to a stub logging the attempt to use those syscalls which should be enough of a clue if they were disabled without proper consideration. They are: timer_create, timer_gettime: timer_getoverrun, timer_settime, timer_delete, clock_adjtime, setitimer, getitimer, alarm. The clock_settime, clock_gettime, clock_getres and clock_nanosleep syscalls are replaced by simple wrappers compatible with CLOCK_REALTIME, CLOCK_MONOTONIC and CLOCK_BOOTTIME only which should cover the vast majority of use cases with very little code. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Richard Cochran <richardcochran@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: Paul Bolle <pebolle@tiscali.nl> Cc: linux-kbuild@vger.kernel.org Cc: netdev@vger.kernel.org Cc: Michal Marek <mmarek@suse.com> Cc: Edward Cree <ecree@solarflare.com> Link: http://lkml.kernel.org/r/1478841010-28605-7-git-send-email-nicolas.pitre@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-14selinux: Clean up initialization of isec->sclassAndreas Gruenbacher
Now that isec->initialized == LABEL_INITIALIZED implies that isec->sclass is valid, skip such inodes immediately in inode_doinit_with_dentry. For the remaining inodes, initialize isec->sclass at the beginning of inode_doinit_with_dentry to simplify the code. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-14proc: Pass file mode to proc_pid_make_inodeAndreas Gruenbacher
Pass the file mode of the proc inode to be created to proc_pid_make_inode. In proc_pid_make_inode, initialize inode->i_mode before calling security_task_to_inode. This allows selinux to set isec->sclass right away without introducing "half-initialized" inode security structs. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-14selinux: Minor cleanupsAndreas Gruenbacher
Fix the comment for function __inode_security_revalidate, which returns an integer. Use the LABEL_* constants consistently for isec->initialized. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-14SELinux: Use GFP_KERNEL for selinux_parse_opts_str().Tetsuo Handa
Since selinux_parse_opts_str() is calling match_strdup() which uses GFP_KERNEL, it is safe to use GFP_KERNEL from kcalloc() which is called by selinux_parse_opts_str(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-10-20mm: Change vm_is_stack_for_task() to vm_is_stack_for_current()Andy Lutomirski
Asking for a non-current task's stack can't be done without races unless the task is frozen in kernel mode. As far as I know, vm_is_stack_for_task() never had a safe non-current use case. The __unused annotation is because some KSTK_ESP implementations ignore their parameter, which IMO is further justification for this patch. Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Jann Horn <jann@thejh.net> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linux API <linux-api@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tycho Andersen <tycho.andersen@canonical.com> Link: http://lkml.kernel.org/r/4c3f68f426e6c061ca98b4fc7ef85ffbb0a25b0c.1475257877.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-10Merge branch 'work.xattr' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs xattr updates from Al Viro: "xattr stuff from Andreas This completes the switch to xattr_handler ->get()/->set() from ->getxattr/->setxattr/->removexattr" * 'work.xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: Remove {get,set,remove}xattr inode operations xattr: Stop calling {get,set,remove}xattr inode operations vfs: Check for the IOP_XATTR flag in listxattr xattr: Add __vfs_{get,set,remove}xattr helpers libfs: Use IOP_XATTR flag for empty directory handling vfs: Use IOP_XATTR flag for bad-inode handling vfs: Add IOP_XATTR inode operations flag vfs: Move xattr_resolve_name to the front of fs/xattr.c ecryptfs: Switch to generic xattr handlers sockfs: Get rid of getxattr iop sockfs: getxattr: Fail with -EOPNOTSUPP for invalid attribute names kernfs: Switch to generic xattr handlers hfs: Switch to generic xattr handlers jffs2: Remove jffs2_{get,set,remove}xattr macros xattr: Remove unnecessary NULL attribute name check
2016-10-07xattr: Add __vfs_{get,set,remove}xattr helpersAndreas Gruenbacher
Right now, various places in the kernel check for the existence of getxattr, setxattr, and removexattr inode operations and directly call those operations. Switch to helper functions and test for the IOP_XATTR flag instead. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Acked-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-19lsm,audit,selinux: Introduce a new audit data type LSM_AUDIT_DATA_FILEVivek Goyal
Right now LSM_AUDIT_DATA_PATH type contains "struct path" in union "u" of common_audit_data. This information is used to print path of file at the same time it is also used to get to dentry and inode. And this inode information is used to get to superblock and device and print device information. This does not work well for layered filesystems like overlay where dentry contained in path is overlay dentry and not the real dentry of underlying file system. That means inode retrieved from dentry is also overlay inode and not the real inode. SELinux helpers like file_path_has_perm() are doing checks on inode retrieved from file_inode(). This returns the real inode and not the overlay inode. That means we are doing check on real inode but for audit purposes we are printing details of overlay inode and that can be confusing while debugging. Hence, introduce a new type LSM_AUDIT_DATA_FILE which carries file information and inode retrieved is real inode using file_inode(). That way right avc denied information is given to user. For example, following is one example avc before the patch. type=AVC msg=audit(1473360868.399:214): avc: denied { read open } for pid=1765 comm="cat" path="/root/.../overlay/container1/merged/readfile" dev="overlay" ino=21443 scontext=unconfined_u:unconfined_r:test_overlay_client_t:s0:c10,c20 tcontext=unconfined_u:object_r:test_overlay_files_ro_t:s0 tclass=file permissive=0 It looks as follows after the patch. type=AVC msg=audit(1473360017.388:282): avc: denied { read open } for pid=2530 comm="cat" path="/root/.../overlay/container1/merged/readfile" dev="dm-0" ino=2377915 scontext=unconfined_u:unconfined_r:test_overlay_client_t:s0:c10,c20 tcontext=unconfined_u:object_r:test_overlay_files_ro_t:s0 tclass=file permissive=0 Notice that now dev information points to "dm-0" device instead of "overlay" device. This makes it clear that check failed on underlying inode and not on the overlay inode. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> [PM: slight tweaks to the description to make checkpatch.pl happy] Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-10selinux: Implement dentry_create_files_as() hookVivek Goyal
Calculate what would be the label of newly created file and set that secid in the passed creds. Context of the task which is actually creating file is retrieved from set of creds passed in. (old->security). Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-08selinux: Pass security pointer to determine_inode_label()Vivek Goyal
Right now selinux_determine_inode_label() works on security pointer of current task. Soon I need this to work on a security pointer retrieved from a set of creds. So start passing in a pointer and caller can decide where to fetch security pointer from. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-08selinux: Implementation for inode_copy_up_xattr() hookVivek Goyal
When a file is copied up in overlay, we have already created file on upper/ with right label and there is no need to copy up selinux label/xattr from lower file to upper file. In fact in case of context mount, we don't want to copy up label as newly created file got its label from context= option. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-08selinux: Implementation for inode_copy_up() hookVivek Goyal
A file is being copied up for overlay file system. Prepare a new set of creds and set create_sid appropriately so that new file is created with appropriate label. Overlay inode has right label for both context and non-context mount cases. In case of non-context mount, overlay inode will have the label of lower file and in case of context mount, overlay inode will have the label from context= mount option. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-08security: Use IS_ENABLED() instead of checking for built-in or moduleJavier Martinez Canillas
The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either built-in or as a module, use that macro instead of open coding the same. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-06Merge branch 'work.const-qstr' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull qstr constification updates from Al Viro: "Fairly self-contained bunch - surprising lot of places passes struct qstr * as an argument when const struct qstr * would suffice; it complicates analysis for no good reason. I'd prefer to feed that separately from the assorted fixes (those are in #for-linus and with somewhat trickier topology)" * 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: qstr: constify instances in adfs qstr: constify instances in lustre qstr: constify instances in f2fs qstr: constify instances in ext2 qstr: constify instances in vfat qstr: constify instances in procfs qstr: constify instances in fuse qstr constify instances in fs/dcache.c qstr: constify instances in nfs qstr: constify instances in ocfs2 qstr: constify instances in autofs4 qstr: constify instances in hfs qstr: constify instances in hfsplus qstr: constify instances in logfs qstr: constify dentry_init_security
2016-07-29Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 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 ...
2016-07-20qstr: constify dentry_init_securityAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-07Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux ↵James Morris
into next
2016-06-27netlabel: Pass a family parameter to netlbl_skbuff_err().Huw Davies
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 <huw@codeweavers.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-06-27calipso: Allow the lsm to label the skbuff directly.Huw Davies
In some cases, the lsm needs to add the label to the skbuff directly. A NF_INET_LOCAL_OUT IPv6 hook is added to selinux to match the IPv4 behaviour. This allows selinux to label the skbuffs that it requires. Signed-off-by: Huw Davies <huw@codeweavers.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-06-24selinux: Add support for unprivileged mounts from user namespacesSeth Forshee
Security labels from unprivileged mounts in user namespaces must be ignored. Force superblocks from user namespaces whose labeling behavior is to use xattrs to use mountpoint labeling instead. For the mountpoint label, default to converting the current task context into a form suitable for file objects, but also allow the policy writer to specify a different label through policy transition rules. Pieced together from code snippets provided by Stephen Smalley. Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2016-06-24fs: Treat foreign mounts as nosuidAndy Lutomirski
If a process gets access to a mount from a different user namespace, that process should not be able to take advantage of setuid files or selinux entrypoints from that filesystem. Prevent this by treating mounts from other mount namespaces and those not owned by current_user_ns() or an ancestor as nosuid. This will make it safer to allow more complex filesystems to be mounted in non-root user namespaces. This does not remove the need for MNT_LOCK_NOSUID. The setuid, setgid, and file capability bits can no longer be abused if code in a user namespace were to clear nosuid on an untrusted filesystem, but this patch, by itself, is insufficient to protect the system from abuse of files that, when execed, would increase MAC privilege. As a more concrete explanation, any task that can manipulate a vfsmount associated with a given user namespace already has capabilities in that namespace and all of its descendents. If they can cause a malicious setuid, setgid, or file-caps executable to appear in that mount, then that executable will only allow them to elevate privileges in exactly the set of namespaces in which they are already privileges. On the other hand, if they can cause a malicious executable to appear with a dangerous MAC label, running it could change the caller's security context in a way that should not have been possible, even inside the namespace in which the task is confined. As a hardening measure, this would have made CVE-2014-5207 much more difficult to exploit. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2016-05-19Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "Highlights: - A new LSM, "LoadPin", from Kees Cook is added, which allows forcing of modules and firmware to be loaded from a specific device (this is from ChromeOS, where the device as a whole is verified cryptographically via dm-verity). This is disabled by default but can be configured to be enabled by default (don't do this if you don't know what you're doing). - Keys: allow authentication data to be stored in an asymmetric key. Lots of general fixes and updates. - SELinux: add restrictions for loading of kernel modules via finit_module(). Distinguish non-init user namespace capability checks. Apply execstack check on thread stacks" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (48 commits) LSM: LoadPin: provide enablement CONFIG Yama: use atomic allocations when reporting seccomp: Fix comment typo ima: add support for creating files using the mknodat syscall ima: fix ima_inode_post_setattr vfs: forbid write access when reading a file into memory fs: fix over-zealous use of "const" selinux: apply execstack check on thread stacks selinux: distinguish non-init user namespace capability checks LSM: LoadPin for kernel file loading restrictions fs: define a string representation of the kernel_read_file_id enumeration Yama: consolidate error reporting string_helpers: add kstrdup_quotable_file string_helpers: add kstrdup_quotable_cmdline string_helpers: add kstrdup_quotable selinux: check ss_initialized before revalidating an inode label selinux: delay inode label lookup as long as possible selinux: don't revalidate an inode's label when explicitly setting it selinux: Change bool variable name to index. KEYS: Add KEYCTL_DH_COMPUTE command ...
2016-05-17Merge branch 'work.const-path' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull 'struct path' constification update from Al Viro: "'struct path' is passed by reference to a bunch of Linux security methods; in theory, there's nothing to stop them from modifying the damn thing and LSM community being what it is, sooner or later some enterprising soul is going to decide that it's a good idea. Let's remove the temptation and constify all of those..." * 'work.const-path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: constify ima_d_path() constify security_sb_pivotroot() constify security_path_chroot() constify security_path_{link,rename} apparmor: remove useless checks for NULL ->mnt constify security_path_{mkdir,mknod,symlink} constify security_path_{unlink,rmdir} apparmor: constify common_perm_...() apparmor: constify aa_path_link() apparmor: new helper - common_path_perm() constify chmod_common/security_path_chmod constify security_sb_mount() constify chown_common/security_path_chown tomoyo: constify assorted struct path * apparmor_path_truncate(): path->mnt is never NULL constify vfs_truncate() constify security_path_truncate() [apparmor] constify struct path * in a bunch of helpers
2016-04-26selinux: apply execstack check on thread stacksStephen Smalley
The execstack check was only being applied on the main process stack. Thread stacks allocated via mmap were only subject to the execmem permission check. Augment the check to apply to the current thread stack as well. Note that this does NOT prevent making a different thread's stack executable. Suggested-by: Nick Kralevich <nnk@google.com> Acked-by: Nick Kralevich <nnk@google.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-04-26selinux: distinguish non-init user namespace capability checksStephen Smalley
Distinguish capability checks against a target associated with the init user namespace versus capability checks against a target associated with a non-init user namespace by defining and using separate security classes for the latter. This is needed to support e.g. Chrome usage of user namespaces for the Chrome sandbox without needing to allow Chrome to also exercise capabilities on targets in the init user namespace. Suggested-by: Dan Walsh <dwalsh@redhat.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-04-19selinux: check ss_initialized before revalidating an inode labelPaul Moore
There is no point in trying to revalidate an inode's security label if the security server is not yet initialized. Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-04-19selinux: delay inode label lookup as long as possiblePaul Moore
Since looking up an inode's label can result in revalidation, delay the lookup as long as possible to limit the performance impact. Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-04-19selinux: don't revalidate an inode's label when explicitly setting itPaul Moore
There is no point in attempting to revalidate an inode's security label when we are in the process of setting it. Reported-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-04-11->getxattr(): pass dentry and inode as separate argumentsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-10don't bother with ->d_inode->i_sb - it's always equal to ->d_sbAl Viro
... and neither can ever be NULL Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>