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* smack: use GFP_NOFS while holding inode_smack::smk_lockEric Biggers2019-10-071-1/+1
| | | | | | | | | | | | | | | | | commit e5bfad3d7acc5702f32aafeb388362994f4d7bd0 upstream. inode_smack::smk_lock is taken during smack_d_instantiate(), which is called during a filesystem transaction when creating a file on ext4. Therefore to avoid a deadlock, all code that takes this lock must use GFP_NOFS, to prevent memory reclaim from waiting for the filesystem transaction to complete. Reported-by: syzbot+0eefc1e06a77d327a056@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Smack: Don't ignore other bprm->unsafe flags if LSM_UNSAFE_PTRACE is setJann Horn2019-10-071-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3675f052b43ba51b99b85b073c7070e083f3e6fb upstream. There is a logic bug in the current smack_bprm_set_creds(): If LSM_UNSAFE_PTRACE is set, but the ptrace state is deemed to be acceptable (e.g. because the ptracer detached in the meantime), the other ->unsafe flags aren't checked. As far as I can tell, this means that something like the following could work (but I haven't tested it): - task A: create task B with fork() - task B: set NO_NEW_PRIVS - task B: install a seccomp filter that makes open() return 0 under some conditions - task B: replace fd 0 with a malicious library - task A: attach to task B with PTRACE_ATTACH - task B: execve() a file with an SMACK64EXEC extended attribute - task A: while task B is still in the middle of execve(), exit (which destroys the ptrace relationship) Make sure that if any flags other than LSM_UNSAFE_PTRACE are set in bprm->unsafe, we reject the execve(). Cc: stable@vger.kernel.org Fixes: 5663884caab1 ("Smack: unify all ptrace accesses in the smack") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* security: smack: Fix possible null-pointer dereferences in ↵Jia-Ju Bai2019-10-071-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | smack_socket_sock_rcv_skb() [ Upstream commit 3f4287e7d98a2954f20bf96c567fdffcd2b63eb9 ] In smack_socket_sock_rcv_skb(), there is an if statement on line 3920 to check whether skb is NULL: if (skb && skb->secmark != 0) This check indicates skb can be NULL in some cases. But on lines 3931 and 3932, skb is used: ad.a.u.net->netif = skb->skb_iif; ipv6_skb_to_auditdata(skb, &ad.a, NULL); Thus, possible null-pointer dereferences may occur when skb is NULL. To fix these possible bugs, an if statement is added to check skb. These bugs are found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* smack: fix access permissions for keyringZoran Markovic2019-02-121-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 5b841bfab695e3b8ae793172a9ff7990f99cc3e2 ] Function smack_key_permission() only issues smack requests for the following operations: - KEY_NEED_READ (issues MAY_READ) - KEY_NEED_WRITE (issues MAY_WRITE) - KEY_NEED_LINK (issues MAY_WRITE) - KEY_NEED_SETATTR (issues MAY_WRITE) A blank smack request is issued in all other cases, resulting in smack access being granted if there is any rule defined between subject and object, or denied with -EACCES otherwise. Request MAY_READ access for KEY_NEED_SEARCH and KEY_NEED_VIEW. Fix the logic in the unlikely case when both MAY_READ and MAY_WRITE are needed. Validate access permission field for valid contents. Signed-off-by: Zoran Markovic <zmarkovic@sierrawireless.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* Smack: Fix handling of IPv4 traffic received by PF_INET6 socketsPiotr Sawicki2018-09-261-5/+9
| | | | | | | | | | | | | | | | [ Upstream commit 129a99890936766f4b69b9da7ed88366313a9210 ] A socket which has sk_family set to PF_INET6 is able to receive not only IPv6 but also IPv4 traffic (IPv4-mapped IPv6 addresses). Prior to this patch, the smk_skb_to_addr_ipv6() could have been called for socket buffers containing IPv4 packets, in result such traffic was allowed. Signed-off-by: Piotr Sawicki <p.sawicki2@partner.samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Smack: Mark inode instant in smack_task_to_inodeCasey Schaufler2018-08-241-0/+1
| | | | | | | | | | | | | | | | [ Upstream commit 7b4e88434c4e7982fb053c49657e1c8bbb8692d9 ] Smack: Mark inode instant in smack_task_to_inode /proc clean-up in commit 1bbc55131e59bd099fdc568d3aa0b42634dbd188 resulted in smack_task_to_inode() being called before smack_d_instantiate. This resulted in the smk_inode value being ignored, even while present for files in /proc/self. Marking the inode as instant here fixes that. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: James Morris <james.morris@microsoft.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* lsm: fix smack_inode_removexattr and xattr_getsecurity memleakCasey Schaufler2017-10-041-30/+25
| | | | | | | | | | | | | | | | | | | | | | | | | security_inode_getsecurity() provides the text string value of a security attribute. It does not provide a "secctx". The code in xattr_getsecurity() that calls security_inode_getsecurity() and then calls security_release_secctx() happened to work because SElinux and Smack treat the attribute and the secctx the same way. It fails for cap_inode_getsecurity(), because that module has no secctx that ever needs releasing. It turns out that Smack is the one that's doing things wrong by not allocating memory when instructed to do so by the "alloc" parameter. The fix is simple enough. Change the security_release_secctx() to kfree() because it isn't a secctx being returned by security_inode_getsecurity(). Change Smack to allocate the string when told to do so. Note: this also fixes memory leaks for LSMs which implement inode_getsecurity but not release_secctx, such as capabilities. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: stable@vger.kernel.org Signed-off-by: James Morris <james.l.morris@oracle.com>
* smack: Remove redundant pdeath_signal clearingKees Cook2017-08-011-15/+0
| | | | | | | | | | | | | This removes the redundant pdeath_signal clearing in Smack: the check in smack_bprm_committing_creds() matches the check in smack_bprm_set_creds() (which used to be in the now-removed smack_bprm_securexec() hook) and since secureexec is now being checked for clearing pdeath_signal, this is redundant to the common exec code. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
* smack: Refactor to remove bprm_secureexec hookKees Cook2017-08-011-17/+4
| | | | | | | | | | | | | | | | The Smack bprm_secureexec hook can be merged with the bprm_set_creds hook since it's dealing with the same information, and all of the details are finalized during the first call to the bprm_set_creds hook via prepare_binprm() (subsequent calls due to binfmt_script, etc, are ignored via bprm->called_set_creds). Here, the test can just happen at the end of the bprm_set_creds hook, and the bprm_secureexec hook can be dropped. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
* exec: Rename bprm->cred_prepared to called_set_credsKees Cook2017-08-011-1/+1
| | | | | | | | | | | | | | | The cred_prepared bprm flag has a misleading name. It has nothing to do with the bprm_prepare_cred hook, and actually tracks if bprm_set_creds has been called. Rename this flag and improve its comment. Cc: David Howells <dhowells@redhat.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: John Johansen <john.johansen@canonical.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Serge Hallyn <serge@hallyn.com>
* Smack: Safer check for a socket in file_receiveCasey Schaufler2017-06-011-1/+1
| | | | | | | | The check of S_ISSOCK() in smack_file_receive() is not appropriate if the passed descriptor is a socket. Reported-by: Stephen Smalley <sds@tyco.nsa.gov> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
* smack: fix double free in smack_parse_opts_str()Tetsuo Handa2017-04-041-3/+1
| | | | | | | | | | | | | smack_parse_opts_str() calls kfree(opts->mnt_opts) when kcalloc() for opts->mnt_opts_flags failed. But it should not have called it because security_free_mnt_opts() will call kfree(opts->mnt_opts). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> fixes: 3bf2789cad9e6573 ("smack: allow mount opts setting over filesystems with binary mount data") Cc: Vivek Trivedi <t.vivek@samsung.com> Cc: Amit Sahrawat <a.sahrawat@samsung.com> Cc: Casey Schaufler <casey@schaufler-ca.com>
* security: mark LSM hooks as __ro_after_initJames Morris2017-03-061-1/+1
| | | | | | | | | Mark all of the registration hooks as __ro_after_init (via the __lsm_ro_after_init macro). Signed-off-by: James Morris <james.l.morris@oracle.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Kees Cook <keescook@chromium.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2017-02-231-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull namespace updates from Eric Biederman: "There is a lot here. A lot of these changes result in subtle user visible differences in kernel behavior. I don't expect anything will care but I will revert/fix things immediately if any regressions show up. From Seth Forshee there is a continuation of the work to make the vfs ready for unpriviled mounts. We had thought the previous changes prevented the creation of files outside of s_user_ns of a filesystem, but it turns we missed the O_CREAT path. Ooops. Pavel Tikhomirov and Oleg Nesterov worked together to fix a long standing bug in the implemenation of PR_SET_CHILD_SUBREAPER where only children that are forked after the prctl are considered and not children forked before the prctl. The only known user of this prctl systemd forks all children after the prctl. So no userspace regressions will occur. Holding earlier forked children to the same rules as later forked children creates a semantic that is sane enough to allow checkpoing of processes that use this feature. There is a long delayed change by Nikolay Borisov to limit inotify instances inside a user namespace. Michael Kerrisk extends the API for files used to maniuplate namespaces with two new trivial ioctls to allow discovery of the hierachy and properties of namespaces. Konstantin Khlebnikov with the help of Al Viro adds code that when a network namespace exits purges it's sysctl entries from the dcache. As in some circumstances this could use a lot of memory. Vivek Goyal fixed a bug with stacked filesystems where the permissions on the wrong inode were being checked. I continue previous work on ptracing across exec. Allowing a file to be setuid across exec while being ptraced if the tracer has enough credentials in the user namespace, and if the process has CAP_SETUID in it's own namespace. Proc files for setuid or otherwise undumpable executables are now owned by the root in the user namespace of their mm. Allowing debugging of setuid applications in containers to work better. A bug I introduced with permission checking and automount is now fixed. The big change is to mark the mounts that the kernel initiates as a result of an automount. This allows the permission checks in sget to be safely suppressed for this kind of mount. As the permission check happened when the original filesystem was mounted. Finally a special case in the mount namespace is removed preventing unbounded chains in the mount hash table, and making the semantics simpler which benefits CRIU. The vfs fix along with related work in ima and evm I believe makes us ready to finish developing and merge fully unprivileged mounts of the fuse filesystem. The cleanups of the mount namespace makes discussing how to fix the worst case complexity of umount. The stacked filesystem fixes pave the way for adding multiple mappings for the filesystem uids so that efficient and safer containers can be implemented" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: proc/sysctl: Don't grab i_lock under sysctl_lock. vfs: Use upper filesystem inode in bprm_fill_uid() proc/sysctl: prune stale dentries during unregistering mnt: Tuck mounts under others instead of creating shadow/side mounts. prctl: propagate has_child_subreaper flag to every descendant introduce the walk_process_tree() helper nsfs: Add an ioctl() to return owner UID of a userns fs: Better permission checking for submounts exit: fix the setns() && PR_SET_CHILD_SUBREAPER interaction vfs: open() with O_CREAT should not create inodes with unknown ids nsfs: Add an ioctl() to return the namespace type proc: Better ownership of files for non-dumpable tasks in user namespaces exec: Remove LSM_UNSAFE_PTRACE_CAP exec: Test the ptracer's saved cred to see if the tracee can gain caps exec: Don't reset euid and egid when the tracee has CAP_SETUID inotify: Convert to using per-namespace limits
| * exec: Remove LSM_UNSAFE_PTRACE_CAPEric W. Biederman2017-01-241-1/+1
| | | | | | | | | | | | | | | | 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>
* | Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/selinux ↵James Morris2017-02-101-30/+1
|\ \ | | | | | | | | | into next
| * | security,selinux,smack: kill security_task_wait hookStephen Smalley2017-01-121-20/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | proc,security: move restriction on writing /proc/pid/attr nodes to procStephen Smalley2017-01-091-10/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | Merge branch 'smack-for-4.11' of git://github.com/cschaufler/smack-next into ↵James Morris2017-01-271-27/+87
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| * | Smack: ignore private inode for file functionsSeung-Woo Kim2017-01-101-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The access to fd from anon_inode is always failed because there is no set xattr operations. So this patch fixes to ignore private inode including anon_inode for file functions. It was only ignored for smack_file_receive() to share dma-buf fd, but dma-buf has other functions like ioctl and mmap. Reference: https://lkml.org/lkml/2015/4/17/16 Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | Smack: fix d_instantiate logic for sockfs and pipefsRafal Krypa2017-01-101-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since 4b936885a (v2.6.32) all inodes on sockfs and pipefs are disconnected. It caused filesystem specific code in smack_d_instantiate to be skipped, because all inodes on those pseudo filesystems were treated as root inodes. As a result all sockfs inodes had the Smack label set to floor. In most cases access checks for sockets use socket_smack data so the inode label is not important. But there are special cases that were broken. One example would be calling fcntl with F_SETOWN command on a socket fd. Now smack_d_instantiate expects all pipefs and sockfs inodes to be disconnected and has the logic in appropriate place. Signed-off-by: Rafal Krypa <r.krypa@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | SMACK: Use smk_tskacc() instead of smk_access() for proper loggingHimanshu Shukla2017-01-101-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | smack_file_open() is first checking the capability of calling subject, this check will skip the SMACK logging for success case. Use smk_tskacc() for proper logging and SMACK access check. Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | Smack: Traverse the smack_known_list using list_for_each_entry_rcu macroVishal Goel2017-01-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In smack_from_secattr function,"smack_known_list" is being traversed using list_for_each_entry macro, although it is a rcu protected structure. So it should be traversed using "list_for_each_entry_rcu" macro to fetch the rcu protected entry. Signed-off-by: Vishal Goel <vishal.goel@samsung.com> Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | SMACK: Free the i_security blob in inode using RCUHimanshu Shukla2017-01-101-4/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is race condition issue while freeing the i_security blob in SMACK module. There is existing condition where i_security can be freed while inode_permission is called from path lookup on second CPU. There has been observed the page fault with such condition. VFS code and Selinux module takes care of this condition by freeing the inode and i_security field using RCU via call_rcu(). But in SMACK directly the i_secuirty blob is being freed. Use call_rcu() to fix this race condition issue. Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Signed-off-by: Vishal Goel <vishal.goel@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | SMACK: Delete list_head repeated initializationHimanshu Shukla2017-01-101-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | smk_copy_rules() and smk_copy_relabel() are initializing list_head though they have been initialized already in new_task_smack() function. Delete repeated initialization. Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | Smack: Fix the issue of wrong SMACK label update in socket bind fail caseVishal Goel2017-01-101-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the issue of wrong SMACK label (SMACK64IPIN) update when a second bind call is made to same IP address & port, but with different SMACK label (SMACK64IPIN) by second instance of server. In this case server returns with "Bind:Address already in use" error but before returning, SMACK label is updated in SMACK port-label mapping list inside smack_socket_bind() hook To fix this issue a new check has been added in smk_ipv6_port_label() function before updating the existing port entry. It checks whether the socket for matching port entry is closed or not. If it is closed then it means port is not bound and it is safe to update the existing port entry else return if port is still getting used. For checking whether socket is closed or not, one more field "smk_can_reuse" has been added in the "smk_port_label" structure. This field will be set to '1' in "smack_sk_free_security()" function which is called to free the socket security blob when the socket is being closed. In this function, port entry is searched in the SMACK port-label mapping list for the closing socket. If entry is found then "smk_can_reuse" field is set to '1'.Initially "smk_can_reuse" field is set to '0' in smk_ipv6_port_label() function after creating a new entry in the list which indicates that socket is in use. Signed-off-by: Vishal Goel <vishal.goel@samsung.com> Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | Smack: Fix the issue of permission denied error in ipv6 hookVishal Goel2017-01-101-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Permission denied error comes when 2 IPv6 servers are running and client tries to connect one of them. Scenario is that both servers are using same IP and port but different protocols(Udp and tcp). They are using different SMACK64IPIN labels.Tcp server is using "test" and udp server is using "test-in". When we try to run tcp client with SMACK64IPOUT label as "test", then connection denied error comes. It should not happen since both tcp server and client labels are same.This happens because there is no check for protocol in smk_ipv6_port_label() function while searching for the earlier port entry. It checks whether there is an existing port entry on the basis of port only. So it updates the earlier port entry in the list. Due to which smack label gets changed for earlier entry in the "smk_ipv6_port_list" list and permission denied error comes. Now a check is added for socket type also.Now if 2 processes use same port but different protocols (tcp or udp), then 2 different port entries will be added in the list. Similarly while checking smack access in smk_ipv6_port_check() function, port entry is searched on the basis of both port and protocol. Signed-off-by: Vishal Goel <vishal.goel@samsung.com> Signed-off-by: Himanshu Shukla <Himanshu.sh@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | SMACK: Add the rcu synchronization mechanism in ipv6 hooksVishal Goel2017-01-101-5/+15
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the rcu synchronization mechanism for accessing smk_ipv6_port_list in smack IPv6 hooks. Access to the port list is vulnerable to a race condition issue,it does not apply proper synchronization methods while working on critical section. It is possible that when one thread is reading the list, at the same time another thread is modifying the same port list, which can cause the major problems. To ensure proper synchronization between two threads, rcu mechanism has been applied while accessing and modifying the port list. RCU will also not affect the performance, as there are more accesses than modification where RCU is most effective synchronization mechanism. Signed-off-by: Vishal Goel <vishal.goel@samsung.com> Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
* / LSM: Add /sys/kernel/security/lsmCasey Schaufler2017-01-191-1/+1
|/ | | | | | | | | | | | | | | | | 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>
* Merge branch 'for-linus' of ↵Linus Torvalds2016-12-161-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: - more ->d_init() stuff (work.dcache) - pathname resolution cleanups (work.namei) - a few missing iov_iter primitives - copy_from_iter_full() and friends. Either copy the full requested amount, advance the iterator and return true, or fail, return false and do _not_ advance the iterator. Quite a few open-coded callers converted (and became more readable and harder to fuck up that way) (work.iov_iter) - several assorted patches, the big one being logfs removal * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: logfs: remove from tree vfs: fix put_compat_statfs64() does not handle errors namei: fold should_follow_link() with the step into not-followed link namei: pass both WALK_GET and WALK_MORE to should_follow_link() namei: invert WALK_PUT logics namei: shift interpretation of LOOKUP_FOLLOW inside should_follow_link() namei: saner calling conventions for mountpoint_last() namei.c: get rid of user_path_parent() switch getfrag callbacks to ..._full() primitives make skb_add_data,{_nocache}() and skb_copy_to_page_nocache() advance only on success [iov_iter] new primitives - copy_from_iter_full() and friends don't open-code file_inode() ceph: switch to use of ->d_init() ceph: unify dentry_operations instances lustre: switch to use of ->d_init()
| * don't open-code file_inode()Al Viro2016-12-041-1/+1
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Smack: Remove unnecessary smack_known_invalidCasey Schaufler2016-11-151-26/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The invalid Smack label ("") and the Huh ("?") Smack label serve the same purpose and having both is unnecessary. While pulling out the invalid label it became clear that the use of smack_from_secid() was inconsistent, so that is repaired. The setting of inode labels to the invalid label could never happen in a functional system, has never been observed in the wild and is not what you'd really want for a failure behavior in any case. That is removed. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
* | Smack: Use GFP_KERNEL for smack_parse_opts_str().Tetsuo Handa2016-11-141-2/+2
| | | | | | | | | | | | | | | | | | Since smack_parse_opts_str() is calling match_strdup() which uses GFP_KERNEL, it is safe to use GFP_KERNEL from kcalloc() which is called by smack_parse_opts_str(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Casey Schaufler <casey@schaufler-ca.com>
* | Smack: ipv6 label match fixCasey Schaufler2016-11-101-6/+6
| | | | | | | | | | | | | | | | | | The check for a deleted entry in the list of IPv6 host addresses was being performed in the wrong place, leading to most peculiar results in some cases. This puts the check into the right place. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
* | SMACK: Fix the memory leak in smack_cred_prepare() hookHimanshu Shukla2016-11-101-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Memory leak in smack_cred_prepare()function. smack_cred_prepare() hook returns error if there is error in allocating memory in smk_copy_rules() or smk_copy_relabel() function. If smack_cred_prepare() function returns error then the calling function should call smack_cred_free() function for cleanup. In smack_cred_free() function first credential is extracted and then all rules are deleted. In smack_cred_prepare() function security field is assigned in the end when all function return success. But this function may return before and memory will not be freed. Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com>
* | SMACK: Do not apply star label in smack_setprocattr hookHimanshu Shukla2016-11-101-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Smack prohibits processes from using the star ("*") and web ("@") labels. Checks have been added in other functions. In smack_setprocattr() hook, only check for web ("@") label has been added and restricted from applying web ("@") label. Check for star ("*") label should also be added in smack_setprocattr() hook. Return error should be "-EINVAL" not "-EPERM" as permission is there for setting label but not the label value as star ("*") or web ("@"). Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com>
* | smack: parse mnt opts after privileges checkHimanshu Shukla2016-11-101-25/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In smack_set_mnt_opts()first the SMACK mount options are being parsed and later it is being checked whether the user calling mount has CAP_MAC_ADMIN capability. This sequence of operationis will allow unauthorized user to add SMACK labels in label list and may cause denial of security attack by adding many labels by allocating kernel memory by unauthorized user. Superblock smack flag is also being set as initialized though function may return with EPERM error. First check the capability of calling user then set the SMACK attributes and smk_flags. Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com>
* | Smack: Assign smack_known_web label for kernel thread'sjooseong lee2016-11-041-2/+10
|/ | | | | | | | | | | Assign smack_known_web label for kernel thread's socket Creating struct sock by sk_alloc function in various kernel subsystems like bluetooth doesn't call smack_socket_post_create(). In such case, received sock label is the floor('_') label and makes access deny. Signed-off-by: jooseong lee <jooseong.lee@samsung.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com>
* Merge branch 'work.xattr' of ↵Linus Torvalds2016-10-101-6/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * xattr: Add __vfs_{get,set,remove}xattr helpersAndreas Gruenbacher2016-10-071-6/+6
| | | | | | | | | | | | | | | | | | | | | | 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>
* | Smack: Signal delivery as an append operationCasey Schaufler2016-09-081-7/+7
|/ | | | | | | | | | | | | Under a strict subject/object security policy delivering a signal or delivering network IPC could be considered either a write or an append operation. The original choice to make both write operations leads to an issue where IPC delivery is desired under policy, but delivery of signals is not. This patch provides the option of making signal delivery an append operation, allowing Smack rules that deny signal delivery while allowing IPC. This was requested for Tizen. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
* Merge branch 'next' of ↵Linus Torvalds2016-07-291-1/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * Merge branch 'smack-for-4.8' of https://github.com/cschaufler/smack-next ↵James Morris2016-07-081-0/+3
| |\ | | | | | | | | | into next
| | * Smack: ignore null signal in smack_task_killRafal Krypa2016-06-081-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <r.krypa@samsung.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com>
| * | Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux ↵James Morris2016-07-071-1/+1
| |\ \ | | |/ | |/| | | | into next
| | * netlabel: Pass a family parameter to netlbl_skbuff_err().Huw Davies2016-06-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | Smack: Handle labels consistently in untrusted mountsSeth Forshee2016-06-241-10/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <seth.forshee@canonical.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* | | Smack: Add support for unprivileged mounts from user namespacesSeth Forshee2016-06-241-11/+30
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <seth.forshee@canonical.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* | switch ->setxattr() to passing dentry and inode separatelyAl Viro2016-05-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <sw0312.kim@samsung.com> Tested-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | ->getxattr(): pass dentry and inode as separate argumentsAl Viro2016-04-111-2/+2
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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