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2017-09-14Merge branch 'work.set_fs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more set_fs removal from Al Viro: "Christoph's 'use kernel_read and friends rather than open-coding set_fs()' series" * 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: unexport vfs_readv and vfs_writev fs: unexport vfs_read and vfs_write fs: unexport __vfs_read/__vfs_write lustre: switch to kernel_write gadget/f_mass_storage: stop messing with the address limit mconsole: switch to kernel_read btrfs: switch write_buf to kernel_write net/9p: switch p9_fd_read to kernel_write mm/nommu: switch do_mmap_private to kernel_read serial2002: switch serial2002_tty_write to kernel_{read/write} fs: make the buf argument to __kernel_write a void pointer fs: fix kernel_write prototype fs: fix kernel_read prototype fs: move kernel_read to fs/read_write.c fs: move kernel_write to fs/read_write.c autofs4: switch autofs4_write to __kernel_write ashmem: switch to ->read_iter
2017-09-12Merge tag 'selinux-pr-20170831' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "A relatively quiet period for SELinux, 11 patches with only two/three having any substantive changes. These noteworthy changes include another tweak to the NNP/nosuid handling, per-file labeling for cgroups, and an object class fix for AF_UNIX/SOCK_RAW sockets; the rest of the changes are minor tweaks or administrative updates (Stephen's email update explains the file explosion in the diffstat). Everything passes the selinux-testsuite" [ Also a couple of small patches from the security tree from Tetsuo Handa for Tomoyo and LSM cleanup. The separation of security policy updates wasn't all that clean - Linus ] * tag 'selinux-pr-20170831' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: constify nf_hook_ops selinux: allow per-file labeling for cgroupfs lsm_audit: update my email address selinux: update my email address MAINTAINERS: update the NetLabel and Labeled Networking information selinux: use GFP_NOWAIT in the AVC kmem_caches selinux: Generalize support for NNP/nosuid SELinux domain transitions selinux: genheaders should fail if too many permissions are defined selinux: update the selinux info in MAINTAINERS credits: update Paul Moore's info selinux: Assign proper class to PF_UNIX/SOCK_RAW sockets tomoyo: Update URLs in Documentation/admin-guide/LSM/tomoyo.rst LSM: Remove security_task_create() hook.
2017-09-11Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull namespace updates from Eric Biederman: "Life has been busy and I have not gotten half as much done this round as I would have liked. I delayed it so that a minor conflict resolution with the mips tree could spend a little time in linux-next before I sent this pull request. This includes two long delayed user namespace changes from Kirill Tkhai. It also includes a very useful change from Serge Hallyn that allows the security capability attribute to be used inside of user namespaces. The practical effect of this is people can now untar tarballs and install rpms in user namespaces. It had been suggested to generalize this and encode some of the namespace information information in the xattr name. Upon close inspection that makes the things that should be hard easy and the things that should be easy more expensive. Then there is my bugfix/cleanup for signal injection that removes the magic encoding of the siginfo union member from the kernel internal si_code. The mips folks reported the case where I had used FPE_FIXME me is impossible so I have remove FPE_FIXME from mips, while at the same time including a return statement in that case to keep gcc from complaining about unitialized variables. I almost finished the work to get make copy_siginfo_to_user a trivial copy to user. The code is available at: git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git neuter-copy_siginfo_to_user-v3 But I did not have time/energy to get the code posted and reviewed before the merge window opened. I was able to see that the security excuse for just copying fields that we know are initialized doesn't work in practice there are buggy initializations that don't initialize the proper fields in siginfo. So we still sometimes copy unitialized data to userspace" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: Introduce v3 namespaced file capabilities mips/signal: In force_fcr31_sig return in the impossible case signal: Remove kernel interal si_code magic fcntl: Don't use ambiguous SIG_POLL si_codes prctl: Allow local CAP_SYS_ADMIN changing exe_file security: Use user_namespace::level to avoid redundant iterations in cap_capable() userns,pidns: Verify the userns for new pid namespaces signal/testing: Don't look for __SI_FAULT in userspace signal/mips: Document a conflict with SI_USER with SIGFPE signal/sparc: Document a conflict with SI_USER with SIGFPE signal/ia64: Document a conflict with SI_USER with SIGFPE signal/alpha: Document a conflict with SI_USER for SIGTRAP
2017-09-07Merge tag 'audit-pr-20170907' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit updates from Paul Moore: "A small pull request for audit this time, only four patches and only two with any real code changes. Those two changes are the removal of a pointless SELinux AVC initialization audit event and a fix to improve the audit timestamp overhead. The other two patches are comment cleanup and administrative updates, nothing very exciting. Everything passes our tests" * tag 'audit-pr-20170907' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: update the function comments selinux: remove AVC init audit log message audit: update the audit info in MAINTAINERS audit: Reduce overhead using a coarse clock
2017-09-07Merge tag 'secureexec-v4.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull secureexec update from Kees Cook: "This series has the ultimate goal of providing a sane stack rlimit when running set*id processes. To do this, the bprm_secureexec LSM hook is collapsed into the bprm_set_creds hook so the secureexec-ness of an exec can be determined early enough to make decisions about rlimits and the resulting memory layouts. Other logic acting on the secureexec-ness of an exec is similarly consolidated. Capabilities needed some special handling, but the refactoring removed other special handling, so that was a wash" * tag 'secureexec-v4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: exec: Consolidate pdeath_signal clearing exec: Use sane stack rlimit under secureexec exec: Consolidate dumpability logic smack: Remove redundant pdeath_signal clearing exec: Use secureexec for clearing pdeath_signal exec: Use secureexec for setting dumpability LSM: drop bprm_secureexec hook commoncap: Move cap_elevated calculation into bprm_set_creds commoncap: Refactor to remove bprm_secureexec hook smack: Refactor to remove bprm_secureexec hook selinux: Refactor to remove bprm_secureexec hook apparmor: Refactor to remove bprm_secureexec hook binfmt: Introduce secureexec flag exec: Correct comments about "point of no return" exec: Rename bprm->cred_prepared to called_set_creds
2017-09-05selinux: remove AVC init audit log messageRichard Guy Briggs
In the process of normalizing audit log messages, it was noticed that the AVC initialization code registered an audit log KERNEL record that didn't fit the standard format. In the process of attempting to normalize it it was determined that this record was not even necessary. Remove it. Ref: http://marc.info/?l=selinux&m=149614868525826&w=2 See: https://github.com/linux-audit/audit-kernel/issues/48 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-09-04fs: fix kernel_write prototypeChristoph Hellwig
Make the position an in/out argument like all the other read/write helpers and and make the buf argument a void pointer. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-04fs: fix kernel_read prototypeChristoph Hellwig
Use proper ssize_t and size_t types for the return value and count argument, move the offset last and make it an in/out argument like all other read/write helpers, and make the buf argument a void pointer to get rid of lots of casts in the callers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-01Introduce v3 namespaced file capabilitiesSerge E. Hallyn
Root in a non-initial user ns cannot be trusted to write a traditional security.capability xattr. If it were allowed to do so, then any unprivileged user on the host could map his own uid to root in a private namespace, write the xattr, and execute the file with privilege on the host. However supporting file capabilities in a user namespace is very desirable. Not doing so means that any programs designed to run with limited privilege must continue to support other methods of gaining and dropping privilege. For instance a program installer must detect whether file capabilities can be assigned, and assign them if so but set setuid-root otherwise. The program in turn must know how to drop partial capabilities, and do so only if setuid-root. This patch introduces v3 of the security.capability xattr. It builds a vfs_ns_cap_data struct by appending a uid_t rootid to struct vfs_cap_data. This is the absolute uid_t (that is, the uid_t in user namespace which mounted the filesystem, usually init_user_ns) of the root id in whose namespaces the file capabilities may take effect. When a task asks to write a v2 security.capability xattr, if it is privileged with respect to the userns which mounted the filesystem, then nothing should change. Otherwise, the kernel will transparently rewrite the xattr as a v3 with the appropriate rootid. This is done during the execution of setxattr() to catch user-space-initiated capability writes. Subsequently, any task executing the file which has the noted kuid as its root uid, or which is in a descendent user_ns of such a user_ns, will run the file with capabilities. Similarly when asking to read file capabilities, a v3 capability will be presented as v2 if it applies to the caller's namespace. If a task writes a v3 security.capability, then it can provide a uid for the xattr so long as the uid is valid in its own user namespace, and it is privileged with CAP_SETFCAP over its namespace. The kernel will translate that rootid to an absolute uid, and write that to disk. After this, a task in the writer's namespace will not be able to use those capabilities (unless rootid was 0), but a task in a namespace where the given uid is root will. Only a single security.capability xattr may exist at a time for a given file. A task may overwrite an existing xattr so long as it is privileged over the inode. Note this is a departure from previous semantics, which required privilege to remove a security.capability xattr. This check can be re-added if deemed useful. This allows a simple setxattr to work, allows tar/untar to work, and allows us to tar in one namespace and untar in another while preserving the capability, without risking leaking privilege into a parent namespace. Example using tar: $ cp /bin/sleep sleepx $ mkdir b1 b2 $ lxc-usernsexec -m b:0:100000:1 -m b:1:$(id -u):1 -- chown 0:0 b1 $ lxc-usernsexec -m b:0:100001:1 -m b:1:$(id -u):1 -- chown 0:0 b2 $ lxc-usernsexec -m b:0:100000:1000 -- tar --xattrs-include=security.capability --xattrs -cf b1/sleepx.tar sleepx $ lxc-usernsexec -m b:0:100001:1000 -- tar --xattrs-include=security.capability --xattrs -C b2 -xf b1/sleepx.tar $ lxc-usernsexec -m b:0:100001:1000 -- getcap b2/sleepx b2/sleepx = cap_sys_admin+ep # /opt/ltp/testcases/bin/getv3xattr b2/sleepx v3 xattr, rootid is 100001 A patch to linux-test-project adding a new set of tests for this functionality is in the nsfscaps branch at github.com/hallyn/ltp Changelog: Nov 02 2016: fix invalid check at refuse_fcap_overwrite() Nov 07 2016: convert rootid from and to fs user_ns (From ebiederm: mar 28 2017) commoncap.c: fix typos - s/v4/v3 get_vfs_caps_from_disk: clarify the fs_ns root access check nsfscaps: change the code split for cap_inode_setxattr() Apr 09 2017: don't return v3 cap for caps owned by current root. return a v2 cap for a true v2 cap in non-init ns Apr 18 2017: . Change the flow of fscap writing to support s_user_ns writing. . Remove refuse_fcap_overwrite(). The value of the previous xattr doesn't matter. Apr 24 2017: . incorporate Eric's incremental diff . move cap_convert_nscap to setxattr and simplify its usage May 8, 2017: . fix leaking dentry refcount in cap_inode_getsecurity Signed-off-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2017-08-28selinux: constify nf_hook_opsArvind Yadav
nf_hook_ops are not supposed to change at runtime. nf_register_net_hooks and nf_unregister_net_hooks are working with const nf_hook_ops. So mark the non-const nf_hook_ops structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-08-22selinux: allow per-file labeling for cgroupfsAntonio Murdaca
This patch allows genfscon per-file labeling for cgroupfs. For instance, this allows to label the "release_agent" file within each cgroup mount and limit writes to it. Signed-off-by: Antonio Murdaca <amurdaca@redhat.com> [PM: subject line and merge tweaks] Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-08-17lsm_audit: update my email addressStephen Smalley
Update my email address since epoch.ncsc.mil no longer exists. MAINTAINERS and CREDITS are already correct. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-08-17selinux: update my email addressStephen Smalley
Update my email address since epoch.ncsc.mil no longer exists. MAINTAINERS and CREDITS are already correct. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-08-08selinux: use GFP_NOWAIT in the AVC kmem_cachesMichal Hocko
There is a strange __GFP_NOMEMALLOC usage pattern in SELinux, specifically GFP_ATOMIC | __GFP_NOMEMALLOC which doesn't make much sense. GFP_ATOMIC on its own allows to access memory reserves while __GFP_NOMEMALLOC dictates we cannot use memory reserves. Replace this with the much more sane GFP_NOWAIT in the AVC code as we can tolerate memory allocation failures in that code. Signed-off-by: Michal Hocko <mhocko@kernel.org> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-08-02selinux: Generalize support for NNP/nosuid SELinux domain transitionsStephen Smalley
As systemd ramps up enabling NNP (NoNewPrivileges) for system services, it is increasingly breaking SELinux domain transitions for those services and their descendants. systemd enables NNP not only for services whose unit files explicitly specify NoNewPrivileges=yes but also for services whose unit files specify any of the following options in combination with running without CAP_SYS_ADMIN (e.g. specifying User= or a CapabilityBoundingSet= without CAP_SYS_ADMIN): SystemCallFilter=, SystemCallArchitectures=, RestrictAddressFamilies=, RestrictNamespaces=, PrivateDevices=, ProtectKernelTunables=, ProtectKernelModules=, MemoryDenyWriteExecute=, or RestrictRealtime= as per the systemd.exec(5) man page. The end result is bad for the security of both SELinux-disabled and SELinux-enabled systems. Packagers have to turn off these options in the unit files to preserve SELinux domain transitions. For users who choose to disable SELinux, this means that they miss out on at least having the systemd-supported protections. For users who keep SELinux enabled, they may still be missing out on some protections because it isn't necessarily guaranteed that the SELinux policy for that service provides the same protections in all cases. commit 7b0d0b40cd78 ("selinux: Permit bounded transitions under NO_NEW_PRIVS or NOSUID.") allowed bounded transitions under NNP in order to support limited usage for sandboxing programs. However, defining typebounds for all of the affected service domains is impractical to implement in policy, since typebounds requires us to ensure that each domain is allowed everything all of its descendant domains are allowed, and this has to be repeated for the entire chain of domain transitions. There is no way to clone all allow rules from descendants to their ancestors in policy currently, and doing so would be undesirable even if it were practical, as it requires leaking permissions to objects and operations into ancestor domains that could weaken their own security in order to allow them to the descendants (e.g. if a descendant requires execmem permission, then so do all of its ancestors; if a descendant requires execute permission to a file, then so do all of its ancestors; if a descendant requires read to a symbolic link or temporary file, then so do all of its ancestors...). SELinux domains are intentionally not hierarchical / bounded in this manner normally, and making them so would undermine their protections and least privilege. We have long had a similar tension with SELinux transitions and nosuid mounts, albeit not as severe. Users often have had to choose between retaining nosuid on a mount and allowing SELinux domain transitions on files within those mounts. This likewise leads to unfortunate tradeoffs in security. Decouple NNP/nosuid from SELinux transitions, so that we don't have to make a choice between them. Introduce a nnp_nosuid_transition policy capability that enables transitions under NNP/nosuid to be based on a permission (nnp_transition for NNP; nosuid_transition for nosuid) between the old and new contexts in addition to the current support for bounded transitions. Domain transitions can then be allowed in policy without requiring the parent to be a strict superset of all of its children. With this change, systemd unit files can be left unmodified from upstream. SELinux-disabled and SELinux-enabled users will benefit from retaining any of the systemd-provided protections. SELinux policy will only need to be adapted to enable the new policy capability and to allow the new permissions between domain pairs as appropriate. NB: Allowing nnp_transition between two contexts opens up the potential for the old context to subvert the new context by installing seccomp filters before the execve. Allowing nosuid_transition between two contexts opens up the potential for a context transition to occur on a file from an untrusted filesystem (e.g. removable media or remote filesystem). Use with care. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-08-01smack: Remove redundant pdeath_signal clearingKees Cook
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>
2017-08-01LSM: drop bprm_secureexec hookKees Cook
This removes the bprm_secureexec hook since the logic has been folded into the bprm_set_creds hook for all LSMs now. Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: John Johansen <john.johansen@canonical.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Serge Hallyn <serge@hallyn.com>
2017-08-01commoncap: Move cap_elevated calculation into bprm_set_credsKees Cook
Instead of a separate function, open-code the cap_elevated test, which lets us entirely remove bprm->cap_effective (to use the local "effective" variable instead), and more accurately examine euid/egid changes via the existing local "is_setid". The following LTP tests were run to validate the changes: # ./runltp -f syscalls -s cap # ./runltp -f securebits # ./runltp -f cap_bounds # ./runltp -f filecaps All kernel selftests for capabilities and exec continue to pass as well. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: James Morris <james.l.morris@oracle.com> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Andy Lutomirski <luto@kernel.org>
2017-08-01commoncap: Refactor to remove bprm_secureexec hookKees Cook
The commoncap implementation of the bprm_secureexec hook is the only LSM that depends on the final call to its bprm_set_creds hook (since it may be called for multiple files, it ignores bprm->called_set_creds). As a result, it cannot safely _clear_ bprm->secureexec since other LSMs may have set it. Instead, remove the bprm_secureexec hook by introducing a new flag to bprm specific to commoncap: cap_elevated. This is similar to cap_effective, but that is used for a specific subset of elevated privileges, and exists solely to track state from bprm_set_creds to bprm_secureexec. As such, it will be removed in the next patch. Here, set the new bprm->cap_elevated flag when setuid/setgid has happened from bprm_fill_uid() or fscapabilities have been prepared. This temporarily moves the bprm_secureexec hook to a static inline. The helper will be removed in the next patch; this makes the step easier to review and bisect, since this does not introduce any changes to inputs nor outputs to the "elevated privileges" calculation. The new flag is merged with the bprm->secureexec flag in setup_new_exec() since this marks the end of any further prepare_binprm() calls. Cc: Andy Lutomirski <luto@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Andy Lutomirski <luto@kernel.org> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Serge Hallyn <serge@hallyn.com>
2017-08-01smack: Refactor to remove bprm_secureexec hookKees Cook
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>
2017-08-01selinux: Refactor to remove bprm_secureexec hookKees Cook
The SELinux 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. Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Paul Moore <paul@paul-moore.com> Tested-by: Paul Moore <paul@paul-moore.com> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Reviewed-by: Andy Lutomirski <luto@kernel.org>
2017-08-01apparmor: Refactor to remove bprm_secureexec hookKees Cook
The AppArmor 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, all the comments describe how secureexec is actually calculated during bprm_set_creds, so this actually does it, drops the bprm flag that was being used internally by AppArmor, and drops the bprm_secureexec hook. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: John Johansen <john.johansen@canonical.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Acked-by: Serge Hallyn <serge@hallyn.com>
2017-08-01exec: Rename bprm->cred_prepared to called_set_credsKees Cook
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>
2017-07-31netfilter: nf_hook_ops structs can be constFlorian Westphal
We no longer place these on a list so they can be const. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-25selinux: Assign proper class to PF_UNIX/SOCK_RAW socketsLuis Ressel
For PF_UNIX, SOCK_RAW is synonymous with SOCK_DGRAM (cf. net/unix/af_unix.c). This is a tad obscure, but libpcap uses it. Signed-off-by: Luis Ressel <aranea@aixah.de> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-07-25sync to Linus v4.13-rc2 for subsystem developers to work againstJames Morris
2017-07-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2017-07-20security: Use user_namespace::level to avoid redundant iterations in ↵Kirill Tkhai
cap_capable() When ns->level is not larger then cred->user_ns->level, then ns can't be cred->user_ns's descendant, and there is no a sense to search in parents. So, break the cycle earlier and skip needless iterations. v2: Change comment on suggested by Andy Lutomirski. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2017-07-19Merge tag 'gcc-plugins-v4.13-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull structure randomization updates from Kees Cook: "Now that IPC and other changes have landed, enable manual markings for randstruct plugin, including the task_struct. This is the rest of what was staged in -next for the gcc-plugins, and comes in three patches, largest first: - mark "easy" structs with __randomize_layout - mark task_struct with an optional anonymous struct to isolate the __randomize_layout section - mark structs to opt _out_ of automated marking (which will come later) And, FWIW, this continues to pass allmodconfig (normal and patched to enable gcc-plugins) builds of x86_64, i386, arm64, arm, powerpc, and s390 for me" * tag 'gcc-plugins-v4.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: randstruct: opt-out externally exposed function pointer structs task_struct: Allow randomized layout randstruct: Mark various structs for randomization
2017-07-18xfrm: remove flow cacheFlorian Westphal
After rcu conversions performance degradation in forward tests isn't that noticeable anymore. See next patch for some numbers. A followup patcg could then also remove genid from the policies as we do not cache bundles anymore. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-18LSM: Remove security_task_create() hook.Tetsuo Handa
Since commit a79be238600d1a03 ("selinux: Use task_alloc hook rather than task_create hook") changed to use task_alloc hook, task_create hook is no longer used. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-07-14KEYS: DH: validate __spare fieldEric Biggers
Syscalls must validate that their reserved arguments are zero and return EINVAL otherwise. Otherwise, it will be impossible to actually use them for anything in the future because existing programs may be passing garbage in. This is standard practice when adding new APIs. Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-07-12include/linux/string.h: add the option of fortified string.h functionsDaniel Micay
This adds support for compiling with a rough equivalent to the glibc _FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer overflow checks for string.h functions when the compiler determines the size of the source or destination buffer at compile-time. Unlike glibc, it covers buffer reads in addition to writes. GNU C __builtin_*_chk intrinsics are avoided because they would force a much more complex implementation. They aren't designed to detect read overflows and offer no real benefit when using an implementation based on inline checks. Inline checks don't add up to much code size and allow full use of the regular string intrinsics while avoiding the need for a bunch of _chk functions and per-arch assembly to avoid wrapper overhead. This detects various overflows at compile-time in various drivers and some non-x86 core kernel code. There will likely be issues caught in regular use at runtime too. Future improvements left out of initial implementation for simplicity, as it's all quite optional and can be done incrementally: * Some of the fortified string functions (strncpy, strcat), don't yet place a limit on reads from the source based on __builtin_object_size of the source buffer. * Extending coverage to more string functions like strlcat. * It should be possible to optionally use __builtin_object_size(x, 1) for some functions (C strings) to detect intra-object overflows (like glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative approach to avoid likely compatibility issues. * The compile-time checks should be made available via a separate config option which can be enabled by default (or always enabled) once enough time has passed to get the issues it catches fixed. Kees said: "This is great to have. While it was out-of-tree code, it would have blocked at least CVE-2016-3858 from being exploitable (improper size argument to strlcpy()). I've sent a number of fixes for out-of-bounds-reads that this detected upstream already" [arnd@arndb.de: x86: fix fortified memcpy] Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de [keescook@chromium.org: avoid panic() in favor of BUG()] Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast [keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help] Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org Signed-off-by: Daniel Micay <danielmicay@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Daniel Axtens <dja@axtens.net> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-05Merge branch 'work.memdup_user' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull memdup_user() conversions from Al Viro: "A fairly self-contained series - hunting down open-coded memdup_user() and memdup_user_nul() instances" * 'work.memdup_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: bpf: don't open-code memdup_user() kimage_file_prepare_segments(): don't open-code memdup_user() ethtool: don't open-code memdup_user() do_ip_setsockopt(): don't open-code memdup_user() do_ipv6_setsockopt(): don't open-code memdup_user() irda: don't open-code memdup_user() xfrm_user_policy(): don't open-code memdup_user() ima_write_policy(): don't open-code memdup_user_nul() sel_write_validatetrans(): don't open-code memdup_user_nul()
2017-07-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: "Reasonably busy this cycle, but perhaps not as busy as in the 4.12 merge window: 1) Several optimizations for UDP processing under high load from Paolo Abeni. 2) Support pacing internally in TCP when using the sch_fq packet scheduler for this is not practical. From Eric Dumazet. 3) Support mutliple filter chains per qdisc, from Jiri Pirko. 4) Move to 1ms TCP timestamp clock, from Eric Dumazet. 5) Add batch dequeueing to vhost_net, from Jason Wang. 6) Flesh out more completely SCTP checksum offload support, from Davide Caratti. 7) More plumbing of extended netlink ACKs, from David Ahern, Pablo Neira Ayuso, and Matthias Schiffer. 8) Add devlink support to nfp driver, from Simon Horman. 9) Add RTM_F_FIB_MATCH flag to RTM_GETROUTE queries, from Roopa Prabhu. 10) Add stack depth tracking to BPF verifier and use this information in the various eBPF JITs. From Alexei Starovoitov. 11) Support XDP on qed device VFs, from Yuval Mintz. 12) Introduce BPF PROG ID for better introspection of installed BPF programs. From Martin KaFai Lau. 13) Add bpf_set_hash helper for TC bpf programs, from Daniel Borkmann. 14) For loads, allow narrower accesses in bpf verifier checking, from Yonghong Song. 15) Support MIPS in the BPF selftests and samples infrastructure, the MIPS eBPF JIT will be merged in via the MIPS GIT tree. From David Daney. 16) Support kernel based TLS, from Dave Watson and others. 17) Remove completely DST garbage collection, from Wei Wang. 18) Allow installing TCP MD5 rules using prefixes, from Ivan Delalande. 19) Add XDP support to Intel i40e driver, from Björn Töpel 20) Add support for TC flower offload in nfp driver, from Simon Horman, Pieter Jansen van Vuuren, Benjamin LaHaise, Jakub Kicinski, and Bert van Leeuwen. 21) IPSEC offloading support in mlx5, from Ilan Tayari. 22) Add HW PTP support to macb driver, from Rafal Ozieblo. 23) Networking refcount_t conversions, From Elena Reshetova. 24) Add sock_ops support to BPF, from Lawrence Brako. This is useful for tuning the TCP sockopt settings of a group of applications, currently via CGROUPs" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1899 commits) net: phy: dp83867: add workaround for incorrect RX_CTRL pin strap dt-bindings: phy: dp83867: provide a workaround for incorrect RX_CTRL pin strap cxgb4: Support for get_ts_info ethtool method cxgb4: Add PTP Hardware Clock (PHC) support cxgb4: time stamping interface for PTP nfp: default to chained metadata prepend format nfp: remove legacy MAC address lookup nfp: improve order of interfaces in breakout mode net: macb: remove extraneous return when MACB_EXT_DESC is defined bpf: add missing break in for the TCP_BPF_SNDCWND_CLAMP case bpf: fix return in load_bpf_file mpls: fix rtm policy in mpls_getroute net, ax25: convert ax25_cb.refcount from atomic_t to refcount_t net, ax25: convert ax25_route.refcount from atomic_t to refcount_t net, ax25: convert ax25_uid_assoc.refcount from atomic_t to refcount_t net, sctp: convert sctp_ep_common.refcnt from atomic_t to refcount_t net, sctp: convert sctp_transport.refcnt from atomic_t to refcount_t net, sctp: convert sctp_chunk.refcnt from atomic_t to refcount_t net, sctp: convert sctp_datamsg.refcnt from atomic_t to refcount_t net, sctp: convert sctp_auth_bytes.refcnt from atomic_t to refcount_t ...
2017-07-05Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security layer updates from James Morris: - a major update for AppArmor. From JJ: * several bug fixes and cleanups * the patch to add symlink support to securityfs that was floated on the list earlier and the apparmorfs changes that make use of securityfs symlinks * it introduces the domain labeling base code that Ubuntu has been carrying for several years, with several cleanups applied. And it converts the current mediation over to using the domain labeling base, which brings domain stacking support with it. This finally will bring the base upstream code in line with Ubuntu and provide a base to upstream the new feature work that Ubuntu carries. * This does _not_ contain any of the newer apparmor mediation features/controls (mount, signals, network, keys, ...) that Ubuntu is currently carrying, all of which will be RFC'd on top of this. - Notable also is the Infiniband work in SELinux, and the new file:map permission. From Paul: "While we're down to 21 patches for v4.13 (it was 31 for v4.12), the diffstat jumps up tremendously with over 2k of line changes. Almost all of these changes are the SELinux/IB work done by Daniel Jurgens; some other noteworthy changes include a NFS v4.2 labeling fix, a new file:map permission, and reporting of policy capabilities on policy load" There's also now genfscon labeling support for tracefs, which was lost in v4.1 with the separation from debugfs. - Smack incorporates a safer socket check in file_receive, and adds a cap_capable call in privilege check. - TPM as usual has a bunch of fixes and enhancements. - Multiple calls to security_add_hooks() can now be made for the same LSM, to allow LSMs to have hook declarations across multiple files. - IMA now supports different "ima_appraise=" modes (eg. log, fix) from the boot command line. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (126 commits) apparmor: put back designators in struct initialisers seccomp: Switch from atomic_t to recount_t seccomp: Adjust selftests to avoid double-join seccomp: Clean up core dump logic IMA: update IMA policy documentation to include pcr= option ima: Log the same audit cause whenever a file has no signature ima: Simplify policy_func_show. integrity: Small code improvements ima: fix get_binary_runtime_size() ima: use ima_parse_buf() to parse template data ima: use ima_parse_buf() to parse measurements headers ima: introduce ima_parse_buf() ima: Add cgroups2 to the defaults list ima: use memdup_user_nul ima: fix up #endif comments IMA: Correct Kconfig dependencies for hash selection ima: define is_ima_appraise_enabled() ima: define Kconfig IMA_APPRAISE_BOOTPARAM option ima: define a set of appraisal rules requiring file signatures ima: extend the "ima_policy" boot command line to support multiple policies ...
2017-07-03Merge tag 'docs-4.13' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "There has been a fair amount of activity in the docs tree this time around. Highlights include: - Conversion of a bunch of security documentation into RST - The conversion of the remaining DocBook templates by The Amazing Mauro Machine. We can now drop the entire DocBook build chain. - The usual collection of fixes and minor updates" * tag 'docs-4.13' of git://git.lwn.net/linux: (90 commits) scripts/kernel-doc: handle DECLARE_HASHTABLE Documentation: atomic_ops.txt is core-api/atomic_ops.rst Docs: clean up some DocBook loose ends Make the main documentation title less Geocities Docs: Use kernel-figure in vidioc-g-selection.rst Docs: fix table problems in ras.rst Docs: Fix breakage with Sphinx 1.5 and upper Docs: Include the Latex "ifthen" package doc/kokr/howto: Only send regression fixes after -rc1 docs-rst: fix broken links to dynamic-debug-howto in kernel-parameters doc: Document suitability of IBM Verse for kernel development Doc: fix a markup error in coding-style.rst docs: driver-api: i2c: remove some outdated information Documentation: DMA API: fix a typo in a function name Docs: Insert missing space to separate link from text doc/ko_KR/memory-barriers: Update control-dependencies example Documentation, kbuild: fix typo "minimun" -> "minimum" docs: Fix some formatting issues in request-key.rst doc: ReSTify keys-trusted-encrypted.txt doc: ReSTify keys-request-key.txt ...
2017-07-03Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle were: - Add the SYSTEM_SCHEDULING bootup state to move various scheduler debug checks earlier into the bootup. This turns silent and sporadically deadly bugs into nice, deterministic splats. Fix some of the splats that triggered. (Thomas Gleixner) - A round of restructuring and refactoring of the load-balancing and topology code (Peter Zijlstra) - Another round of consolidating ~20 of incremental scheduler code history: this time in terms of wait-queue nomenclature. (I didn't get much feedback on these renaming patches, and we can still easily change any names I might have misplaced, so if anyone hates a new name, please holler and I'll fix it.) (Ingo Molnar) - sched/numa improvements, fixes and updates (Rik van Riel) - Another round of x86/tsc scheduler clock code improvements, in hope of making it more robust (Peter Zijlstra) - Improve NOHZ behavior (Frederic Weisbecker) - Deadline scheduler improvements and fixes (Luca Abeni, Daniel Bristot de Oliveira) - Simplify and optimize the topology setup code (Lauro Ramos Venancio) - Debloat and decouple scheduler code some more (Nicolas Pitre) - Simplify code by making better use of llist primitives (Byungchul Park) - ... plus other fixes and improvements" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits) sched/cputime: Refactor the cputime_adjust() code sched/debug: Expose the number of RT/DL tasks that can migrate sched/numa: Hide numa_wake_affine() from UP build sched/fair: Remove effective_load() sched/numa: Implement NUMA node level wake_affine() sched/fair: Simplify wake_affine() for the single socket case sched/numa: Override part of migrate_degrades_locality() when idle balancing sched/rt: Move RT related code from sched/core.c to sched/rt.c sched/deadline: Move DL related code from sched/core.c to sched/deadline.c sched/cpuset: Only offer CONFIG_CPUSETS if SMP is enabled sched/fair: Spare idle load balancing on nohz_full CPUs nohz: Move idle balancer registration to the idle path sched/loadavg: Generalize "_idle" naming to "_nohz" sched/core: Drop the unused try_get_task_struct() helper function sched/fair: WARN() and refuse to set buddy when !se->on_rq sched/debug: Fix SCHED_WARN_ON() to return a value on !CONFIG_SCHED_DEBUG as well sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming sched/wait: Move bit_wait_table[] and related functionality from sched/core.c to sched/wait_bit.c sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h> sched/wait: Re-adjust macro line continuation backslashes in <linux/wait.h> ...
2017-07-03Merge tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuidLinus Torvalds
Pull uuid subsystem from Christoph Hellwig: "This is the new uuid subsystem, in which Amir, Andy and I have started consolidating our uuid/guid helpers and improving the types used for them. Note that various other subsystems have pulled in this tree, so I'd like it to go in early. UUID/GUID summary: - introduce the new uuid_t/guid_t types that are going to replace the somewhat confusing uuid_be/uuid_le types and make the terminology fit the various specs, as well as the userspace libuuid library. (me, based on a previous version from Amir) - consolidated generic uuid/guid helper functions lifted from XFS and libnvdimm (Amir and me) - conversions to the new types and helpers (Amir, Andy and me)" * tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuid: (34 commits) ACPI: hns_dsaf_acpi_dsm_guid can be static mmc: sdhci-pci: make guid intel_dsm_guid static uuid: Take const on input of uuid_is_null() and guid_is_null() thermal: int340x_thermal: fix compile after the UUID API switch thermal: int340x_thermal: Switch to use new generic UUID API acpi: always include uuid.h ACPI: Switch to use generic guid_t in acpi_evaluate_dsm() ACPI / extlog: Switch to use new generic UUID API ACPI / bus: Switch to use new generic UUID API ACPI / APEI: Switch to use new generic UUID API acpi, nfit: Switch to use new generic UUID API MAINTAINERS: add uuid entry tmpfs: generate random sb->s_uuid scsi_debug: switch to uuid_t nvme: switch to uuid_t sysctl: switch to use uuid_t partitions/ldm: switch to use uuid_t overlayfs: use uuid_t instead of uuid_be fs: switch ->s_uuid to uuid_t ima/policy: switch to use uuid_t ...
2017-06-30randstruct: Mark various structs for randomizationKees Cook
This marks many critical kernel structures for randomization. These are structures that have been targeted in the past in security exploits, or contain functions pointers, pointers to function pointer tables, lists, workqueues, ref-counters, credentials, permissions, or are otherwise sensitive. This initial list was extracted from Brad Spengler/PaX Team's code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Left out of this list is task_struct, which requires special handling and will be covered in a subsequent patch. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-06-30ima_write_policy(): don't open-code memdup_user_nul()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-28apparmor: put back designators in struct initialisersStephen Rothwell
Fixes: 8014370f1257 ("apparmor: move path_link mediation to using labels") Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: John Johansen <john.johansen@canonical.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-23Merge branch 'stable-4.13' of git://git.infradead.org/users/pcmoore/selinux ↵James Morris
into next
2017-06-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Two entries being added at the same time to the IFLA policy table, whilst parallel bug fixes to decnet routing dst handling overlapping with the dst gc removal in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-21ima: Log the same audit cause whenever a file has no signatureThiago Jung Bauermann
If the file doesn't have an xattr, ima_appraise_measurement sets cause to "missing-hash" while if there's an xattr but it's a digest instead of a signature it sets cause to "IMA-signature-required". Fix it by setting cause to "IMA-signature-required" in both cases. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-06-21ima: Simplify policy_func_show.Thiago Jung Bauermann
If the func_tokens array uses the same indices as enum ima_hooks, policy_func_show can be a lot simpler, and the func_* enum becomes unnecessary. Also, if we use the same macro trick used by kernel_read_file_id_str we can use one hooks list for both the enum and the string array, making sure they are always in sync (suggested by Mimi Zohar). Finally, by using the printf pattern for the function token directly instead of using the pt macro we can simplify policy_func_show even further and avoid needing a temporary buffer. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-06-21integrity: Small code improvementsThiago Jung Bauermann
These changes are too small to warrant their own patches: The keyid and sig_size members of struct signature_v2_hdr are in BE format, so use a type that makes this assumption explicit. Also, use beXX_to_cpu instead of __beXX_to_cpu to read them. Change integrity_kernel_read to take a void * buffer instead of char * buffer, so that callers don't have to use a cast if they provide a buffer that isn't a char *. Add missing #endif comment in ima.h pointing out which macro it refers to. Add missing fall through comment in ima_appraise.c. Constify mask_tokens and func_tokens arrays. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-06-21ima: fix get_binary_runtime_size()Roberto Sassu
Remove '+ 1' from 'size += strlen(entry->template_desc->name) + 1;', as the template name is sent to userspace without the '\0' character. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-06-21ima: use ima_parse_buf() to parse template dataRoberto Sassu
The binary_field_data structure definition has been removed from ima_restore_template_data(). The lengths and data pointers are directly stored into the template_data array of the ima_template_entry structure. For template data, both the number of fields and buffer end checks can be done, as these information are known (respectively from the template descriptor, and from the measurement header field). Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-06-21ima: use ima_parse_buf() to parse measurements headersRoberto Sassu
The binary_hdr_v1 and binary_data_v1 structures defined in ima_restore_measurement_list() have been replaced with an array of four ima_field_data structures where pcr, digest, template name and template data lengths and pointers are stored. The length of pcr and digest in the ima_field_data array and the bits in the bitmap are set before ima_parse_buf() is called. The ENFORCE_FIELDS bit is set for all entries except the last one (there is still data to parse), and ENFORCE_BUFEND is set only for the last entry. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>