summaryrefslogtreecommitdiff
path: root/security/smack
AgeCommit message (Collapse)Author
2019-12-10smack: use GFP_NOFS while holding inode_smack::smk_lockEric Biggers
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 Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [bwh: Backported to 3.16: - Drop change to smk_netlbl_mls(), where GFP_ATOMIC is used - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-12-10Smack: Don't ignore other bprm->unsafe flags if LSM_UNSAFE_PTRACE is setJann Horn
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(). 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> [bwh: Backported to 3.16: Ignore LSM_UNSAFE_PTRACE_CAP, which is also handled by the preceding if-statement.] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-01security: let security modules use PTRACE_MODE_* with bitmasksJann Horn
commit 3dfb7d8cdbc7ea0c2970450e60818bb3eefbad69 upstream. It looks like smack and yama weren't aware that the ptrace mode can have flags ORed into it - PTRACE_MODE_NOAUDIT until now, but only for /proc/$pid/stat, and with the PTRACE_MODE_*CREDS patch, all modes have flags ORed into them. Signed-off-by: Jann Horn <jann@thejh.net> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: "Serge E. Hallyn" <serge.hallyn@ubuntu.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-01lsm: fix smack_inode_removexattr and xattr_getsecurity memleakCasey Schaufler
commit 57e7ba04d422c3d41c8426380303ec9b7533ded9 upstream. 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> Signed-off-by: James Morris <james.l.morris@oracle.com> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-01Smack: remove unneeded NULL-termination from securtity labelKonstantin Khlebnikov
commit da1b63566c469bf3e2b24182114422e16b1aa34c upstream. Values of extended attributes are stored as binary blobs. NULL-termination of them isn't required. It just wastes disk space and confuses command-line tools like getfattr because they have to print that zero byte at the end. This patch removes terminating zero byte from initial security label in smack_inode_init_security and cuts it out in function smack_inode_getsecurity which is used by syscall getxattr. This change seems completely safe, because function smk_parse_smack ignores everything after first zero byte. Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2015-08-20sysfs: Create mountpoints with sysfs_create_mount_pointEric W. Biederman
commit f9bb48825a6b5d02f4cabcc78967c75db903dcdc upstream. This allows for better documentation in the code and it allows for a simpler and fully correct version of fs_fully_visible to be written. The mount points converted and their filesystems are: /sys/hypervisor/s390/ s390_hypfs /sys/kernel/config/ configfs /sys/kernel/debug/ debugfs /sys/firmware/efi/efivars/ efivarfs /sys/fs/fuse/connections/ fusectl /sys/fs/pstore/ pstore /sys/kernel/tracing/ tracefs /sys/fs/cgroup/ cgroup /sys/kernel/security/ securityfs /sys/fs/selinux/ selinuxfs /sys/fs/smackfs/ smackfs Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2015-02-24smack: fix possible use after frees in task_security() callersAndrey Ryabinin
commit 6d1cff2a885850b78b40c34777b46cf5da5d1050 upstream. We hit use after free on dereferncing pointer to task_smack struct in smk_of_task() called from smack_task_to_inode(). task_security() macro uses task_cred_xxx() to get pointer to the task_smack. task_cred_xxx() could be used only for non-pointer members of task's credentials. It cannot be used for pointer members since what they point to may disapper after dropping RCU read lock. Mainly task_security() used this way: smk_of_task(task_security(p)) Intead of this introduce function smk_of_task_struct() which takes task_struct as argument and returns pointer to smk_known struct and do this under RCU read lock. Bogus task_security() macro is not used anymore, so remove it. KASan's report for this: AddressSanitizer: use after free in smack_task_to_inode+0x50/0x70 at addr c4635600 ============================================================================= BUG kmalloc-64 (Tainted: PO): kasan error ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Allocated in new_task_smack+0x44/0xd8 age=39 cpu=0 pid=1866 kmem_cache_alloc_trace+0x88/0x1bc new_task_smack+0x44/0xd8 smack_cred_prepare+0x48/0x21c security_prepare_creds+0x44/0x4c prepare_creds+0xdc/0x110 smack_setprocattr+0x104/0x150 security_setprocattr+0x4c/0x54 proc_pid_attr_write+0x12c/0x194 vfs_write+0x1b0/0x370 SyS_write+0x5c/0x94 ret_fast_syscall+0x0/0x48 INFO: Freed in smack_cred_free+0xc4/0xd0 age=27 cpu=0 pid=1564 kfree+0x270/0x290 smack_cred_free+0xc4/0xd0 security_cred_free+0x34/0x3c put_cred_rcu+0x58/0xcc rcu_process_callbacks+0x738/0x998 __do_softirq+0x264/0x4cc do_softirq+0x94/0xf4 irq_exit+0xbc/0x120 handle_IRQ+0x104/0x134 gic_handle_irq+0x70/0xac __irq_svc+0x44/0x78 _raw_spin_unlock+0x18/0x48 sync_inodes_sb+0x17c/0x1d8 sync_filesystem+0xac/0xfc vdfs_file_fsync+0x90/0xc0 vfs_fsync_range+0x74/0x7c INFO: Slab 0xd3b23f50 objects=32 used=31 fp=0xc4635600 flags=0x4080 INFO: Object 0xc4635600 @offset=5632 fp=0x (null) Bytes b4 c46355f0: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Object c4635600: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object c4635610: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object c4635620: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object c4635630: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk. Redzone c4635640: bb bb bb bb .... Padding c46356e8: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Padding c46356f8: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ CPU: 5 PID: 834 Comm: launchpad_prelo Tainted: PBO 3.10.30 #1 Backtrace: [<c00233a4>] (dump_backtrace+0x0/0x158) from [<c0023dec>] (show_stack+0x20/0x24) r7:c4634010 r6:d3b23f50 r5:c4635600 r4:d1002140 [<c0023dcc>] (show_stack+0x0/0x24) from [<c06d6d7c>] (dump_stack+0x20/0x28) [<c06d6d5c>] (dump_stack+0x0/0x28) from [<c01c1d50>] (print_trailer+0x124/0x144) [<c01c1c2c>] (print_trailer+0x0/0x144) from [<c01c1e88>] (object_err+0x3c/0x44) r7:c4635600 r6:d1002140 r5:d3b23f50 r4:c4635600 [<c01c1e4c>] (object_err+0x0/0x44) from [<c01cac18>] (kasan_report_error+0x2b8/0x538) r6:d1002140 r5:d3b23f50 r4:c6429cf8 r3:c09e1aa7 [<c01ca960>] (kasan_report_error+0x0/0x538) from [<c01c9430>] (__asan_load4+0xd4/0xf8) [<c01c935c>] (__asan_load4+0x0/0xf8) from [<c031e168>] (smack_task_to_inode+0x50/0x70) r5:c4635600 r4:ca9da000 [<c031e118>] (smack_task_to_inode+0x0/0x70) from [<c031af64>] (security_task_to_inode+0x3c/0x44) r5:cca25e80 r4:c0ba9780 [<c031af28>] (security_task_to_inode+0x0/0x44) from [<c023d614>] (pid_revalidate+0x124/0x178) r6:00000000 r5:cca25e80 r4:cbabe3c0 r3:00008124 [<c023d4f0>] (pid_revalidate+0x0/0x178) from [<c01db98c>] (lookup_fast+0x35c/0x43y4) r9:c6429efc r8:00000101 r7:c079d940 r6:c6429e90 r5:c6429ed8 r4:c83c4148 [<c01db630>] (lookup_fast+0x0/0x434) from [<c01deec8>] (do_last.isra.24+0x1c0/0x1108) [<c01ded08>] (do_last.isra.24+0x0/0x1108) from [<c01dff04>] (path_openat.isra.25+0xf4/0x648) [<c01dfe10>] (path_openat.isra.25+0x0/0x648) from [<c01e1458>] (do_filp_open+0x3c/0x88) [<c01e141c>] (do_filp_open+0x0/0x88) from [<c01ccb28>] (do_sys_open+0xf0/0x198) r7:00000001 r6:c0ea2180 r5:0000000b r4:00000000 [<c01cca38>] (do_sys_open+0x0/0x198) from [<c01ccc00>] (SyS_open+0x30/0x34) [<c01ccbd0>] (SyS_open+0x0/0x34) from [<c001db80>] (ret_fast_syscall+0x0/0x48) Read of size 4 by thread T834: Memory state around the buggy address: c4635380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc c4635400: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc c4635480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc c4635500: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc c4635580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >c4635600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ c4635680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb c4635700: 00 00 00 00 04 fc fc fc fc fc fc fc fc fc fc fc c4635780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc c4635800: 00 00 00 00 00 00 04 fc fc fc fc fc fc fc fc fc c4635880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> [ luis: backported to 3.16: - dropped changes to smk_bu_task() - adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-05-20Merge branch 'smack-for-3.16' of git://git.gitorious.org/smack-next/kernel ↵James Morris
into next
2014-05-06Warning in scanf string typingToralf Förster
This fixes a warning about the mismatch of types between the declared unsigned and integer. Signed-off-by: Toralf Förster <toralf.foerster@gmx.de>
2014-04-30Smack: Label cgroup files for systemdCasey Schaufler
The cgroup filesystem isn't ready for an LSM to properly use extented attributes. This patch makes files created in the cgroup filesystem usable by a system running Smack and systemd. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2014-04-23Smack: Verify read access on file open - v3Casey Schaufler
Smack believes that many of the operatons that can be performed on an open file descriptor are read operations. The fstat and lseek system calls are examples. An implication of this is that files shouldn't be open if the task doesn't have read access even if it has write access and the file is being opened write only. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2014-04-11Smack: bidirectional UDS connect checkCasey Schaufler
Smack IPC policy requires that the sender have write access to the receiver. UDS streams don't do per-packet checks. The only check is done at connect time. The existing code checks if the connecting process can write to the other, but not the other way around. This change adds a check that the other end can write to the connecting process. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schuafler <casey@schaufler-ca.com>
2014-04-11Smack: Correctly remove SMACK64TRANSMUTE attributeCasey Schaufler
Sam Henderson points out that removing the SMACK64TRANSMUTE attribute from a directory does not result in the directory transmuting. This is because the inode flag indicating that the directory is transmuting isn't cleared. The fix is a tad less than trivial because smk_task and smk_mmap should have been broken out, too. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2014-04-11SMACK: Fix handling value==NULL in post setxattrJosé Bollo
The function `smack_inode_post_setxattr` is called each time that a setxattr is done, for any value of name. The kernel allow to put value==NULL when size==0 to set an empty attribute value. The systematic call to smk_import_entry was causing the dereference of a NULL pointer hence a KERNEL PANIC! The problem can be produced easily by issuing the command `setfattr -n user.data file` under bash prompt when SMACK is active. Moving the call to smk_import_entry as proposed by this patch is correcting the behaviour because the function smack_inode_post_setxattr is called for the SMACK's attributes only if the function smack_inode_setxattr validated the value and its size (what will not be the case when size==0). It also has a benefical effect to not fill the smack hash with garbage values coming from any extended attribute write. Change-Id: Iaf0039c2be9bccb6cee11c24a3b44d209101fe47 Signed-off-by: José Bollo <jose.bollo@open.eurogiciel.org>
2014-04-11bugfix patch for SMACKPankaj Kumar
1. In order to remove any SMACK extended attribute from a file, a user should have CAP_MAC_ADMIN capability. But user without having this capability is able to remove SMACK64MMAP security attribute. 2. While validating size and value of smack extended attribute in smack_inode_setsecurity hook, wrong error code is returned. Signed-off-by: Pankaj Kumar <pamkaj.k2@samsung.com> Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com>
2014-04-11Smack: adds smackfs/ptrace interfaceLukasz Pawelczyk
This allows to limit ptrace beyond the regular smack access rules. It adds a smackfs/ptrace interface that allows smack to be configured to require equal smack labels for PTRACE_MODE_ATTACH access. See the changes in Documentation/security/Smack.txt below for details. Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com> Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2014-04-11Smack: unify all ptrace accesses in the smackLukasz Pawelczyk
The decision whether we can trace a process is made in the following functions: smack_ptrace_traceme() smack_ptrace_access_check() smack_bprm_set_creds() (in case the proces is traced) This patch unifies all those decisions by introducing one function that checks whether ptrace is allowed: smk_ptrace_rule_check(). This makes possible to actually trace with TRACEME where first the TRACEME itself must be allowed and then exec() on a traced process. Additional bugs fixed: - The decision is made according to the mode parameter that is now correctly translated from PTRACE_MODE_* to MAY_* instead of being treated 1:1. PTRACE_MODE_READ requires MAY_READ. PTRACE_MODE_ATTACH requires MAY_READWRITE. - Add a smack audit log in case of exec() refused by bprm_set_creds(). - Honor the PTRACE_MODE_NOAUDIT flag and don't put smack audit info in case this flag is set. Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com> Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2014-04-11Smack: fix the subject/object order in smack_ptrace_traceme()Lukasz Pawelczyk
The order of subject/object is currently reversed in smack_ptrace_traceme(). It is currently checked if the tracee has a capability to trace tracer and according to this rule a decision is made whether the tracer will be allowed to trace tracee. Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com> Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2014-04-11Minor improvement of 'smack_sb_kern_mount'José Bollo
Fix a possible memory access fault when transmute is true and isp is NULL. Signed-off-by: José Bollo <jose.bollo@open.eurogiciel.org>
2014-03-14smack: fix key permission verificationDmitry Kasatkin
For any keyring access type SMACK always used MAY_READWRITE access check. It prevents reading the key with label "_", which should be allowed for anyone. This patch changes default access check to MAY_READ and use MAY_READWRITE in only appropriate cases. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2014-03-14KEYS: Move the flags representing required permission to linux/key.hDavid Howells
Move the flags representing required permission to linux/key.h as the perm parameter of security_key_permission() is in terms of them - and not the permissions mask flags used in key->perm. Whilst we're at it: (1) Rename them to be KEY_NEED_xxx rather than KEY_xxx to avoid collisions with symbols in uapi/linux/input.h. (2) Don't use key_perm_t for a mask of required permissions, but rather limit it to the permissions mask attached to the key and arguments related directly to that. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
2014-01-23Merge git://git.infradead.org/users/eparis/auditLinus Torvalds
Pull audit update from Eric Paris: "Again we stayed pretty well contained inside the audit system. Venturing out was fixing a couple of function prototypes which were inconsistent (didn't hurt anything, but we used the same value as an int, uint, u32, and I think even a long in a couple of places). We also made a couple of minor changes to when a couple of LSMs called the audit system. We hoped to add aarch64 audit support this go round, but it wasn't ready. I'm disappearing on vacation on Thursday. I should have internet access, but it'll be spotty. If anything goes wrong please be sure to cc rgb@redhat.com. He'll make fixing things his top priority" * git://git.infradead.org/users/eparis/audit: (50 commits) audit: whitespace fix in kernel-parameters.txt audit: fix location of __net_initdata for audit_net_ops audit: remove pr_info for every network namespace audit: Modify a set of system calls in audit class definitions audit: Convert int limit uses to u32 audit: Use more current logging style audit: Use hex_byte_pack_upper audit: correct a type mismatch in audit_syscall_exit() audit: reorder AUDIT_TTY_SET arguments audit: rework AUDIT_TTY_SET to only grab spin_lock once audit: remove needless switch in AUDIT_SET audit: use define's for audit version audit: documentation of audit= kernel parameter audit: wait_for_auditd rework for readability audit: update MAINTAINERS audit: log task info on feature change audit: fix incorrect set of audit_sock audit: print error message when fail to create audit socket audit: fix dangling keywords in audit_log_set_loginuid() output audit: log on errors from filter user rules ...
2014-01-13smack: call WARN_ONCE() instead of calling audit_log_start()Richard Guy Briggs
Remove the call to audit_log() (which call audit_log_start()) and deal with the errors in the caller, logging only once if the condition is met. Calling audit_log_start() in this location makes buffer allocation and locking more complicated in the calling tree (audit_filter_user()). Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
2013-12-31Smack: File receive audit correctionCasey Schaufler
Eric Paris politely points out: Inside smack_file_receive() it seems like you are initting the audit field with LSM_AUDIT_DATA_TASK. And then use smk_ad_setfield_u_fs_path(). Seems like LSM_AUDIT_DATA_PATH would make more sense. (and depending on how it's used fix a crash...) He is correct. This puts things in order. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-31Smack: Rationalize mount restrictionsCasey Schaufler
The mount restrictions imposed by Smack rely heavily on the use of the filesystem "floor", which is the label that all processes writing to the filesystem must have access to. It turns out that while the "floor" notion is sound, it has yet to be fully implemented and has never been used. The sb_mount and sb_umount hooks only make sense if the filesystem floor is used actively, and it isn't. They can be reintroduced if a rational restriction comes up. Until then, they get removed. The sb_kern_mount hook is required for the option processing. It is too permissive in the case of unprivileged mounts, effectively bypassing the CAP_MAC_ADMIN restrictions if any of the smack options are specified. Unprivileged mounts are no longer allowed to set Smack filesystem options. Additionally, the root and default values are set to the label of the caller, in keeping with the policy that objects get the label of their creator. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-23Smack: change rule cap checkCasey Schaufler
smk_write_change_rule() is calling capable rather than the more correct smack_privileged(). This allows for setting rules in violation of the onlycap facility. This is the simple repair. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-23Smack: Make the syslog control configurableCasey Schaufler
The syslog control requires that the calling proccess have the floor ("_") Smack label. Tizen does not run any processes except for kernel helpers with the floor label. This changes allows the admin to configure a specific label for syslog. The default value is the star ("*") label, effectively removing the restriction. The value can be set using smackfs/syslog for anyone who wants a more restrictive behavior. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-19Smack: Prevent the * and @ labels from being used in SMACK64EXECCasey Schaufler
Smack prohibits processes from using the star ("*") and web ("@") labels because we don't want files with those labels getting created implicitly. All setting of those labels should be done explicitly. The trouble is that there is no check for these labels in the processing of SMACK64EXEC. That is repaired. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-11smack: fix: allow either entry be missing on access/access2 check (v2)Jarkko Sakkinen
This is a regression caused by f7112e6c. When either subject or object is not found the answer for access should be no. This patch fixes the situation. '0' is written back instead of failing with -EINVAL. v2: cosmetic style fixes Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2013-10-28Smack: Ptrace access check modeCasey Schaufler
When the ptrace security hooks were split the addition of a mode parameter was not taken advantage of in the Smack ptrace access check. This changes the access check from always looking for read and write access to using the passed mode. This will make use of /proc much happier. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-10-18Smack: Implement lock security modeCasey Schaufler
Linux file locking does not follow the same rules as other mechanisms. Even though it is a write operation a process can set a read lock on files which it has open only for read access. Two programs with read access to a file can use read locks to communicate. This is not acceptable in a Mandatory Access Control environment. Smack treats setting a read lock as the write operation that it is. Unfortunately, many programs assume that setting a read lock is a read operation. These programs are unhappy in the Smack environment. This patch introduces a new access mode (lock) to address this problem. A process with lock access to a file can set a read lock. A process with write access to a file can set a read lock or a write lock. This prevents a situation where processes are granted write access just so they can set read locks. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-09-07Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "Nothing major for this kernel, just maintenance updates" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (21 commits) apparmor: add the ability to report a sha1 hash of loaded policy apparmor: export set of capabilities supported by the apparmor module apparmor: add the profile introspection file to interface apparmor: add an optional profile attachment string for profiles apparmor: add interface files for profiles and namespaces apparmor: allow setting any profile into the unconfined state apparmor: make free_profile available outside of policy.c apparmor: rework namespace free path apparmor: update how unconfined is handled apparmor: change how profile replacement update is done apparmor: convert profile lists to RCU based locking apparmor: provide base for multiple profiles to be replaced at once apparmor: add a features/policy dir to interface apparmor: enable users to query whether apparmor is enabled apparmor: remove minimum size check for vmalloc() Smack: parse multiple rules per write to load2, up to PAGE_SIZE-1 bytes Smack: network label match fix security: smack: add a hash table to quicken smk_find_entry() security: smack: fix memleak in smk_write_rules_list() xattr: Constify ->name member of "struct xattr". ...
2013-08-23Merge branch 'smack-for-3.12' of git://git.gitorious.org/smack-next/kernel ↵James Morris
into ra-next
2013-08-12Smack: parse multiple rules per write to load2, up to PAGE_SIZE-1 bytesRafal Krypa
Smack interface for loading rules has always parsed only single rule from data written to it. This requires user program to call one write() per each rule it wants to load. This change makes it possible to write multiple rules, separated by new line character. Smack will load at most PAGE_SIZE-1 characters and properly return number of processed bytes. In case when user buffer is larger, it will be additionally truncated. All characters after last \n will not get parsed to avoid partial rule near input buffer boundary. Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2013-08-06Smack: IPv6 casting error fix for 3.11Casey Schaufler
The original implementation of the Smack IPv6 port based local controls works most of the time using a sockaddr as a temporary variable, but not always as it overflows in some circumstances. The correct data is a sockaddr_in6. A struct sockaddr isn't as large as a struct sockaddr_in6. There would need to be casting one way or the other. This patch gets it the right way. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-08-01Smack: network label match fixCasey Schaufler
The Smack code that matches incoming CIPSO tags with Smack labels reaches through the NetLabel interfaces and compares the network data with the CIPSO header associated with a Smack label. This was done in a ill advised attempt to optimize performance. It works so long as the categories fit in a single capset, but this isn't always the case. This patch changes the Smack code to use the appropriate NetLabel interfaces to compare the incoming CIPSO header with the CIPSO header associated with a label. It will always match the CIPSO headers correctly. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-08-01security: smack: add a hash table to quicken smk_find_entry()Tomasz Stanislawski
Accepted for the smack-next tree after changing the number of slots from 128 to 16. This patch adds a hash table to quicken searching of a smack label by its name. Basically, the patch improves performance of SMACK initialization. Parsing of rules involves translation from a string to a smack_known (aka label) entity which is done in smk_find_entry(). The current implementation of the function iterates over a global list of smack_known resulting in O(N) complexity for smk_find_entry(). The total complexity of SMACK initialization becomes O(rules * labels). Therefore it scales quadratically with a complexity of a system. Applying the patch reduced the complexity of smk_find_entry() to O(1) as long as number of label is in hundreds. If the number of labels is increased please update SMACK_HASH_SLOTS constant defined in security/smack/smack.h. Introducing the configuration of this constant with Kconfig or cmdline might be a good idea. The size of the hash table was adjusted experimentally. The rule set used by TIZEN contains circa 17K rules for 500 labels. The table above contains results of SMACK initialization using 'time smackctl apply' bash command. The 'Ref' is a kernel without this patch applied. The consecutive values refers to value of SMACK_HASH_SLOTS. Every measurement was repeated three times to reduce noise. | Ref | 1 | 2 | 4 | 8 | 16 | 32 | 64 | 128 | 256 | 512 -------------------------------------------------------------------------------------------- Run1 | 1.156 | 1.096 | 0.883 | 0.764 | 0.692 | 0.667 | 0.649 | 0.633 | 0.634 | 0.629 | 0.620 Run2 | 1.156 | 1.111 | 0.885 | 0.764 | 0.694 | 0.661 | 0.649 | 0.651 | 0.634 | 0.638 | 0.623 Run3 | 1.160 | 1.107 | 0.886 | 0.764 | 0.694 | 0.671 | 0.661 | 0.638 | 0.631 | 0.624 | 0.638 AVG | 1.157 | 1.105 | 0.885 | 0.764 | 0.693 | 0.666 | 0.653 | 0.641 | 0.633 | 0.630 | 0.627 Surprisingly, a single hlist is slightly faster than a double-linked list. The speed-up saturates near 64 slots. Therefore I chose value 128 to provide some margin if more labels were used. It looks that IO becomes a new bottleneck. Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
2013-08-01security: smack: fix memleak in smk_write_rules_list()Tomasz Stanislawski
The smack_parsed_rule structure is allocated. If a rule is successfully installed then the last reference to the object is lost. This patch fixes this leak. Moreover smack_parsed_rule is allocated on stack because it no longer needed ofter smk_write_rules_list() is finished. Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
2013-07-25xattr: Constify ->name member of "struct xattr".Tetsuo Handa
Since everybody sets kstrdup()ed constant string to "struct xattr"->name but nobody modifies "struct xattr"->name , we can omit kstrdup() and its failure checking by constifying ->name member of "struct xattr". Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Joel Becker <jlbec@evilplan.org> [ocfs2] Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Paul Moore <paul@paul-moore.com> Tested-by: Paul Moore <paul@paul-moore.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-07-09Merge tag 'nfs-for-3.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client updates from Trond Myklebust: "Feature highlights include: - Add basic client support for NFSv4.2 - Add basic client support for Labeled NFS (selinux for NFSv4.2) - Fix the use of credentials in NFSv4.1 stateful operations, and add support for NFSv4.1 state protection. Bugfix highlights: - Fix another NFSv4 open state recovery race - Fix an NFSv4.1 back channel session regression - Various rpc_pipefs races - Fix another issue with NFSv3 auth negotiation Please note that Labeled NFS does require some additional support from the security subsystem. The relevant changesets have all been reviewed and acked by James Morris." * tag 'nfs-for-3.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (54 commits) NFS: Set NFS_CS_MIGRATION for NFSv4 mounts NFSv4.1 Refactor nfs4_init_session and nfs4_init_channel_attrs nfs: have NFSv3 try server-specified auth flavors in turn nfs: have nfs_mount fake up a auth_flavs list when the server didn't provide it nfs: move server_authlist into nfs_try_mount_request nfs: refactor "need_mount" code out of nfs_try_mount SUNRPC: PipeFS MOUNT notification optimization for dying clients SUNRPC: split client creation routine into setup and registration SUNRPC: fix races on PipeFS UMOUNT notifications SUNRPC: fix races on PipeFS MOUNT notifications NFSv4.1 use pnfs_device maxcount for the objectlayout gdia_maxcount NFSv4.1 use pnfs_device maxcount for the blocklayout gdia_maxcount NFSv4.1 Fix gdia_maxcount calculation to fit in ca_maxresponsesize NFS: Improve legacy idmapping fallback NFSv4.1 end back channel session draining NFS: Apply v4.1 capabilities to v4.2 NFSv4.1: Clean up layout segment comparison helper names NFSv4.1: layout segment comparison helpers should take 'const' parameters NFSv4: Move the DNS resolver into the NFSv4 module rpc_pipefs: only set rpc_dentry_ops if d_op isn't already set ...
2013-06-08Security: Add Hook to test if the particular xattr is part of a MAC model.David Quigley
The interface to request security labels from user space is the xattr interface. When requesting the security label from an NFS server it is important to make sure the requested xattr actually is a MAC label. This allows us to make sure that we get the desired semantics from the attribute instead of something else such as capabilities or a time based LSM. Acked-by: Eric Paris <eparis@redhat.com> Acked-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Matthew N. Dodd <Matthew.Dodd@sparta.com> Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg> Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg> Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-03Smack: Fix the bug smackcipso can't set CIPSO correctlyPassion,Zhao
Bug report: https://tizendev.org/bugs/browse/TDIS-3891 The reason is userspace libsmack only use "smackfs/cipso2" long-label interface, but the code's logical is still for orginal fixed length label. Now update smack_cipso_apply() to support flexible label (<=256 including tailing '\0') There is also a bug in kernel/security/smack/smackfs.c: When smk_set_cipso() parsing the CIPSO setting from userspace, the offset of CIPSO level should be "strlen(label)+1" instead of "strlen(label)" Signed-off-by: Passion,Zhao <passion.zhao@intel.com>
2013-05-28Smack: Fix possible NULL pointer dereference at smk_netlbl_mls()Tetsuo Handa
netlbl_secattr_catmap_alloc(GFP_ATOMIC) can return NULL. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2013-05-28Smack: Add smkfstransmute mount optionCasey Schaufler
Suppliment the smkfsroot mount option with another, smkfstransmute, that does the same thing but also marks the root inode as transmutting. This allows a freshly created filesystem to be mounted with a transmutting heirarchy. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-05-28Smack: Improve access check performanceCasey Schaufler
Each Smack label that the kernel has seen is added to a list of labels. The list of access rules for a given subject label hangs off of the label list entry for the label. This patch changes the structures that contain subject labels to point at the label list entry rather that the label itself. Doing so removes a label list lookup in smk_access() that was accounting for the largest single chunk of Smack overhead. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-05-28Smack: Local IPv6 port based controlsCasey Schaufler
Smack does not provide access controls on IPv6 communications. This patch introduces a mechanism for maintaining Smack lables for local IPv6 communications. It is based on labeling local ports. The behavior should be compatible with any future "real" IPv6 support as it provides no interfaces for users to manipulate the labeling. Remote IPv6 connections use the ambient label the same way that unlabeled IPv4 packets are treated. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-04-03Smack: include magic.h in smackfs.cCasey Schaufler
As reported for linux-next: Tree for Apr 2 (smack) Add the required include for smackfs.c Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reported-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-03-19Fix NULL pointer dereference in smack_inode_unlink() and smack_inode_rmdir()Igor Zhbanov
This patch fixes kernel Oops because of wrong common_audit_data type in smack_inode_unlink() and smack_inode_rmdir(). When SMACK security module is enabled and SMACK logging is on (/smack/logging is not zero) and you try to delete the file which 1) you cannot delete due to SMACK rules and logging of failures is on or 2) you can delete and logging of success is on, you will see following: Unable to handle kernel NULL pointer dereference at virtual address 000002d7 [<...>] (strlen+0x0/0x28) [<...>] (audit_log_untrustedstring+0x14/0x28) [<...>] (common_lsm_audit+0x108/0x6ac) [<...>] (smack_log+0xc4/0xe4) [<...>] (smk_curacc+0x80/0x10c) [<...>] (smack_inode_unlink+0x74/0x80) [<...>] (security_inode_unlink+0x2c/0x30) [<...>] (vfs_unlink+0x7c/0x100) [<...>] (do_unlinkat+0x144/0x16c) The function smack_inode_unlink() (and smack_inode_rmdir()) need to log two structures of different types. First of all it does: smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, dentry); This will set common audit data type to LSM_AUDIT_DATA_DENTRY and store dentry for auditing (by function smk_curacc(), which in turn calls dump_common_audit_data(), which is actually uses provided data and logs it). /* * You need write access to the thing you're unlinking */ rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad); if (rc == 0) { /* * You also need write access to the containing directory */ Then this function wants to log anoter data: smk_ad_setfield_u_fs_path_dentry(&ad, NULL); smk_ad_setfield_u_fs_inode(&ad, dir); The function sets inode field, but don't change common_audit_data type. rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); } So the dump_common_audit() function incorrectly interprets inode structure as dentry, and Oops will happen. This patch reinitializes common_audit_data structures with correct type. Also I removed unneeded smk_ad_setfield_u_fs_path_dentry(&ad, NULL); initialization, because both dentry and inode pointers are stored in the same union. Signed-off-by: Igor Zhbanov <i.zhbanov@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
2013-03-19Smack: add support for modification of existing rulesRafal Krypa
Rule modifications are enabled via /smack/change-rule. Format is as follows: "Subject Object rwaxt rwaxt" First two strings are subject and object labels up to 255 characters. Third string contains permissions to enable. Fourth string contains permissions to disable. All unmentioned permissions will be left unchanged. If no rule previously existed, it will be created. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2013-03-19smack: SMACK_MAGIC to include/uapi/linux/magic.hJarkko Sakkinen
SMACK_MAGIC moved to a proper place for easy user space access (i.e. libsmack). Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@iki.fi>