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2011-02-11security: add cred argument to security_capable()Chris Wright
Expand security_capable() to include cred, so that it can be usable in a wider range of call sites. Signed-off-by: Chris Wright <chrisw@sous-sol.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-01-10Merge branch 'master' into nextJames Morris
Conflicts: security/smack/smack_lsm.c Verified and added fix by Stephen Rothwell <sfr@canb.auug.org.au> Ok'd by Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-01-07Merge branch 'vfs-scale-working' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin * 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin: (57 commits) fs: scale mntget/mntput fs: rename vfsmount counter helpers fs: implement faster dentry memcmp fs: prefetch inode data in dcache lookup fs: improve scalability of pseudo filesystems fs: dcache per-inode inode alias locking fs: dcache per-bucket dcache hash locking bit_spinlock: add required includes kernel: add bl_list xfs: provide simple rcu-walk ACL implementation btrfs: provide simple rcu-walk ACL implementation ext2,3,4: provide simple rcu-walk ACL implementation fs: provide simple rcu-walk generic_check_acl implementation fs: provide rcu-walk aware permission i_ops fs: rcu-walk aware d_revalidate method fs: cache optimise dentry and inode for rcu-walk fs: dcache reduce branches in lookup path fs: dcache remove d_mounted fs: fs_struct use seqlock fs: rcu-walk for path lookup ...
2011-01-07fs: rcu-walk for path lookupNick Piggin
Perform common cases of path lookups without any stores or locking in the ancestor dentry elements. This is called rcu-walk, as opposed to the current algorithm which is a refcount based walk, or ref-walk. This results in far fewer atomic operations on every path element, significantly improving path lookup performance. It also avoids cacheline bouncing on common dentries, significantly improving scalability. The overall design is like this: * LOOKUP_RCU is set in nd->flags, which distinguishes rcu-walk from ref-walk. * Take the RCU lock for the entire path walk, starting with the acquiring of the starting path (eg. root/cwd/fd-path). So now dentry refcounts are not required for dentry persistence. * synchronize_rcu is called when unregistering a filesystem, so we can access d_ops and i_ops during rcu-walk. * Similarly take the vfsmount lock for the entire path walk. So now mnt refcounts are not required for persistence. Also we are free to perform mount lookups, and to assume dentry mount points and mount roots are stable up and down the path. * Have a per-dentry seqlock to protect the dentry name, parent, and inode, so we can load this tuple atomically, and also check whether any of its members have changed. * Dentry lookups (based on parent, candidate string tuple) recheck the parent sequence after the child is found in case anything changed in the parent during the path walk. * inode is also RCU protected so we can load d_inode and use the inode for limited things. * i_mode, i_uid, i_gid can be tested for exec permissions during path walk. * i_op can be loaded. When we reach the destination dentry, we lock it, recheck lookup sequence, and increment its refcount and mountpoint refcount. RCU and vfsmount locks are dropped. This is termed "dropping rcu-walk". If the dentry refcount does not match, we can not drop rcu-walk gracefully at the current point in the lokup, so instead return -ECHILD (for want of a better errno). This signals the path walking code to re-do the entire lookup with a ref-walk. Aside from the final dentry, there are other situations that may be encounted where we cannot continue rcu-walk. In that case, we drop rcu-walk (ie. take a reference on the last good dentry) and continue with a ref-walk. Again, if we can drop rcu-walk gracefully, we return -ECHILD and do the whole lookup using ref-walk. But it is very important that we can continue with ref-walk for most cases, particularly to avoid the overhead of double lookups, and to gain the scalability advantages on common path elements (like cwd and root). The cases where rcu-walk cannot continue are: * NULL dentry (ie. any uncached path element) * parent with d_inode->i_op->permission or ACLs * dentries with d_revalidate * Following links In future patches, permission checks and d_revalidate become rcu-walk aware. It may be possible eventually to make following links rcu-walk aware. Uncached path elements will always require dropping to ref-walk mode, at the very least because i_mutex needs to be grabbed, and objects allocated. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-05af_unix: Avoid socket->sk NULL OOPS in stream connect security hooks.David S. Miller
unix_release() can asynchornously set socket->sk to NULL, and it does so without holding the unix_state_lock() on "other" during stream connects. However, the reverse mapping, sk->sk_socket, is only transitioned to NULL under the unix_state_lock(). Therefore make the security hooks follow the reverse mapping instead of the forward mapping. Reported-by: Jeremy Fitzhardinge <jeremy@goop.org> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-01security: Fix comment of security_key_permissionTetsuo Handa
Comment for return value of security_key_permission() has been wrong since it was added in 2.6.15. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
2010-11-15capabilities/syslog: open code cap_syslog logic to fix build failureEric Paris
The addition of CONFIG_SECURITY_DMESG_RESTRICT resulted in a build failure when CONFIG_PRINTK=n. This is because the capabilities code which used the new option was built even though the variable in question didn't exist. The patch here fixes this by moving the capabilities checks out of the LSM and into the caller. All (known) LSMs should have been calling the capabilities hook already so it actually makes the code organization better to eliminate the hook altogether. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-21security: secid_to_secctx returns len when data is NULLEric Paris
With the (long ago) interface change to have the secid_to_secctx functions do the string allocation instead of having the caller do the allocation we lost the ability to query the security server for the length of the upcoming string. The SECMARK code would like to allocate a netlink skb with enough length to hold the string but it is just too unclean to do the string allocation twice or to do the allocation the first time and hold onto the string and slen. This patch adds the ability to call security_secid_to_secctx() with a NULL data pointer and it will just set the slen pointer. Signed-off-by: Eric Paris <eparis@redhat.com> Reviewed-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-10-21secmark: make secmark object handling genericEric Paris
Right now secmark has lots of direct selinux calls. Use all LSM calls and remove all SELinux specific knowledge. The only SELinux specific knowledge we leave is the mode. The only point is to make sure that other LSMs at least test this generic code before they assume it works. (They may also have to make changes if they do not represent labels as strings) Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Paul Moore <paul.moore@hp.com> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: James Morris <jmorris@namei.org>
2010-10-21security: remove unused parameter from security_task_setscheduler()KOSAKI Motohiro
All security modules shouldn't change sched_param parameter of security_task_setscheduler(). This is not only meaningless, but also make a harmful result if caller pass a static variable. This patch remove policy and sched_param parameter from security_task_setscheduler() becuase none of security module is using it. Cc: James Morris <jmorris@namei.org> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-08-10Merge branch 'writable_limits' of git://decibel.fi.muni.cz/~xslaby/linuxLinus Torvalds
* 'writable_limits' of git://decibel.fi.muni.cz/~xslaby/linux: unistd: add __NR_prlimit64 syscall numbers rlimits: implement prlimit64 syscall rlimits: switch more rlimit syscalls to do_prlimit rlimits: redo do_setrlimit to more generic do_prlimit rlimits: add rlimit64 structure rlimits: do security check under task_lock rlimits: allow setrlimit to non-current tasks rlimits: split sys_setrlimit rlimits: selinux, do rlimits changes under task_lock rlimits: make sure ->rlim_max never grows in sys_setrlimit rlimits: add task_struct to update_rlimit_cpu rlimits: security, add task_struct to setrlimit Fix up various system call number conflicts. We not only added fanotify system calls in the meantime, but asm-generic/unistd.h added a wait4 along with a range of reserved per-architecture system calls.
2010-08-10Merge branch 'for-linus' of git://git.infradead.org/users/eparis/notifyLinus Torvalds
* 'for-linus' of git://git.infradead.org/users/eparis/notify: (132 commits) fanotify: use both marks when possible fsnotify: pass both the vfsmount mark and inode mark fsnotify: walk the inode and vfsmount lists simultaneously fsnotify: rework ignored mark flushing fsnotify: remove global fsnotify groups lists fsnotify: remove group->mask fsnotify: remove the global masks fsnotify: cleanup should_send_event fanotify: use the mark in handler functions audit: use the mark in handler functions dnotify: use the mark in handler functions inotify: use the mark in handler functions fsnotify: send fsnotify_mark to groups in event handling functions fsnotify: Exchange list heads instead of moving elements fsnotify: srcu to protect read side of inode and vfsmount locks fsnotify: use an explicit flag to indicate fsnotify_destroy_mark has been called fsnotify: use _rcu functions for mark list traversal fsnotify: place marks on object in order of group memory address vfs/fsnotify: fsnotify_close can delay the final work in fput fsnotify: store struct file not struct path ... Fix up trivial delete/modify conflict in fs/notify/inotify/inotify.c.
2010-08-02LSM: Remove unused arguments from security_path_truncate().Tetsuo Handa
When commit be6d3e56a6b9b3a4ee44a0685e39e595073c6f0d "introduce new LSM hooks where vfsmount is available." was proposed, regarding security_path_truncate(), only "struct file *" argument (which AppArmor wanted to use) was removed. But length and time_attrs arguments are not used by TOMOYO nor AppArmor. Thus, let's remove these arguments. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Nick Piggin <npiggin@suse.de> Signed-off-by: James Morris <jmorris@namei.org>
2010-07-28fsnotify: new fsnotify hooks and events types for access decisionsEric Paris
introduce a new fsnotify hook, fsnotify_perm(), which is called from the security code. This hook is used to allow fsnotify groups to make access control decisions about events on the system. We also must change the generic fsnotify function to return an error code if we intend these hooks to be in any way useful. Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-16rlimits: security, add task_struct to setrlimitJiri Slaby
Add task_struct to task_setrlimit of security_operations to be able to set rlimit of task other than current. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Acked-by: Eric Paris <eparis@redhat.com> Acked-by: James Morris <jmorris@namei.org>
2010-05-06Merge branch 'master' into nextJames Morris
2010-04-12security: remove dead hook acctEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook key_session_to_parentEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook task_setgroupsEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook task_setgidEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook task_setuidEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook cred_commitEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook inode_deleteEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook sb_post_pivotrootEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook sb_post_addmountEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook sb_post_remountEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook sb_umount_busyEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove dead hook sb_umount_closeEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12security: remove sb_check_sb hooksEric Paris
Unused hook. Remove it. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-02-24Security: add static to security_ops and default_security_ops variablewzt.wzt@gmail.com
Enhance the security framework to support resetting the active security module. This eliminates the need for direct use of the security_ops and default_security_ops variables outside of security.c, so make security_ops and default_security_ops static. Also remove the secondary_ops variable as a cleanup since there is no use for that. secondary_ops was originally used by SELinux to call the "secondary" security module (capability or dummy), but that was replaced by direct calls to capability and the only remaining use is to save and restore the original security ops pointer value if SELinux is disabled by early userspace based on /etc/selinux/config. Further, if we support this directly in the security framework, then we can just use &default_security_ops for this purpose since that is now available. Signed-off-by: Zhitong Wang <zhitong.wangzt@alibaba-inc.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2010-02-04syslog: distinguish between /proc/kmsg and syscallsKees Cook
This allows the LSM to distinguish between syslog functions originating from /proc/kmsg access and direct syscalls. By default, the commoncaps will now no longer require CAP_SYS_ADMIN to read an opened /proc/kmsg file descriptor. For example the kernel syslog reader can now drop privileges after opening /proc/kmsg, instead of staying privileged with CAP_SYS_ADMIN. MAC systems that implement security_syslog have unchanged behavior. Signed-off-by: Kees Cook <kees.cook@canonical.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-01-18Merge branch 'master' into nextJames Morris
2010-01-11LSM: Update comment on security_sock_rcv_skbTetsuo Handa
It is not permitted to do sleeping operation inside security_sock_rcv_skb(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> -- Signed-off-by: James Morris <jmorris@namei.org>
2009-12-17NOMMU: Optimise away the {dac_,}mmap_min_addr testsDavid Howells
In NOMMU mode clamp dac_mmap_min_addr to zero to cause the tests on it to be skipped by the compiler. We do this as the minimum mmap address doesn't make any sense in NOMMU mode. mmap_min_addr and round_hint_to_min() can be discarded entirely in NOMMU mode. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-11-10security: report the module name to security_module_requestEric Paris
For SELinux to do better filtering in userspace we send the name of the module along with the AVC denial when a program is denied module_request. Example output: type=SYSCALL msg=audit(11/03/2009 10:59:43.510:9) : arch=x86_64 syscall=write success=yes exit=2 a0=3 a1=7fc28c0d56c0 a2=2 a3=7fffca0d7440 items=0 ppid=1727 pid=1729 auid=unset uid=root gid=root euid=root suid=root fsuid=root egid=root sgid=root fsgid=root tty=(none) ses=unset comm=rpc.nfsd exe=/usr/sbin/rpc.nfsd subj=system_u:system_r:nfsd_t:s0 key=(null) type=AVC msg=audit(11/03/2009 10:59:43.510:9) : avc: denied { module_request } for pid=1729 comm=rpc.nfsd kmod="net-pf-10" scontext=system_u:system_r:nfsd_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=system Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-10-12LSM: Add security_path_chroot().Tetsuo Handa
This patch allows pathname based LSM modules to check chroot() operations. This hook is used by TOMOYO. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
2009-10-12LSM: Add security_path_chmod() and security_path_chown().Tetsuo Handa
This patch allows pathname based LSM modules to check chmod()/chown() operations. Since notify_change() does not receive "struct vfsmount *", we add security_path_chmod() and security_path_chown() to the caller of notify_change(). These hooks are used by TOMOYO. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-24sysctl: remove "struct file *" argument of ->proc_handlerAlexey Dobriyan
It's unused. It isn't needed -- read or write flag is already passed and sysctl shouldn't care about the rest. It _was_ used in two places at arch/frv for some reason. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-10LSM/SELinux: inode_{get,set,notify}secctx hooks to access LSM security ↵David P. Quigley
context information. This patch introduces three new hooks. The inode_getsecctx hook is used to get all relevant information from an LSM about an inode. The inode_setsecctx is used to set both the in-core and on-disk state for the inode based on a context derived from inode_getsecctx.The final hook inode_notifysecctx will notify the LSM of a change for the in-core state of the inode in question. These hooks are for use in the labeled NFS code and addresses concerns of how to set security on an inode in a multi-xattr LSM. For historical reasons Stephen Smalley's explanation of the reason for these hooks is pasted below. Quote Stephen Smalley inode_setsecctx: Change the security context of an inode. Updates the in core security context managed by the security module and invokes the fs code as needed (via __vfs_setxattr_noperm) to update any backing xattrs that represent the context. Example usage: NFS server invokes this hook to change the security context in its incore inode and on the backing file system to a value provided by the client on a SETATTR operation. inode_notifysecctx: Notify the security module of what the security context of an inode should be. Initializes the incore security context managed by the security module for this inode. Example usage: NFS client invokes this hook to initialize the security context in its incore inode to the value provided by the server for the file when the server returned the file's attributes to the client. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-07KEYS: Fix default security_session_to_parent()David Howells
Fix the default security_session_to_parent() in linux/security.h to have a body. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-07KEYS: security_cred_alloc_blank() should return int under all circumstancesDavid Howells
Make security_cred_alloc_blank() return int, not void, when CONFIG_SECURITY=n. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-02KEYS: Add a keyctl to install a process's session keyring on its parent [try #6]David Howells
Add a keyctl to install a process's session keyring onto its parent. This replaces the parent's session keyring. Because the COW credential code does not permit one process to change another process's credentials directly, the change is deferred until userspace next starts executing again. Normally this will be after a wait*() syscall. To support this, three new security hooks have been provided: cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in the blank security creds and key_session_to_parent() - which asks the LSM if the process may replace its parent's session keyring. The replacement may only happen if the process has the same ownership details as its parent, and the process has LINK permission on the session keyring, and the session keyring is owned by the process, and the LSM permits it. Note that this requires alteration to each architecture's notify_resume path. This has been done for all arches barring blackfin, m68k* and xtensa, all of which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the replacement to be performed at the point the parent process resumes userspace execution. This allows the userspace AFS pioctl emulation to fully emulate newpag() and the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to alter the parent process's PAG membership. However, since kAFS doesn't use PAGs per se, but rather dumps the keys into the session keyring, the session keyring of the parent must be replaced if, for example, VIOCSETTOK is passed the newpag flag. This can be tested with the following program: #include <stdio.h> #include <stdlib.h> #include <keyutils.h> #define KEYCTL_SESSION_TO_PARENT 18 #define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0) int main(int argc, char **argv) { key_serial_t keyring, key; long ret; keyring = keyctl_join_session_keyring(argv[1]); OSERROR(keyring, "keyctl_join_session_keyring"); key = add_key("user", "a", "b", 1, keyring); OSERROR(key, "add_key"); ret = keyctl(KEYCTL_SESSION_TO_PARENT); OSERROR(ret, "KEYCTL_SESSION_TO_PARENT"); return 0; } Compiled and linked with -lkeyutils, you should see something like: [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: _ses 355907932 --alswrv 4043 -1 \_ keyring: _uid.4043 [dhowells@andromeda ~]$ /tmp/newpag [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: _ses 1055658746 --alswrv 4043 4043 \_ user: a [dhowells@andromeda ~]$ /tmp/newpag hello [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: hello 340417692 --alswrv 4043 4043 \_ user: a Where the test program creates a new session keyring, sticks a user key named 'a' into it and then installs it on its parent. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-01lsm: Add hooks to the TUN driverPaul Moore
The TUN driver lacks any LSM hooks which makes it difficult for LSM modules, such as SELinux, to enforce access controls on network traffic generated by TUN users; this is particularly problematic for virtualization apps such as QEMU and KVM. This patch adds three new LSM hooks designed to control the creation and attachment of TUN devices, the hooks are: * security_tun_dev_create() Provides access control for the creation of new TUN devices * security_tun_dev_post_create() Provides the ability to create the necessary socket LSM state for newly created TUN devices * security_tun_dev_attach() Provides access control for attaching to existing, persistent TUN devices and the ability to update the TUN device's socket LSM state as necessary Signed-off-by: Paul Moore <paul.moore@hp.com> Acked-by: Eric Paris <eparis@parisplace.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: James Morris <jmorris@namei.org>
2009-08-14security: update documentation for security_request_moduleJames Morris
Update documentation for security_request_module to indicate return value, as suggested by Serge Hallyn. Signed-off-by: James Morris <jmorris@namei.org>
2009-08-14security: introducing security_request_moduleEric Paris
Calling request_module() will trigger a userspace upcall which will load a new module into the kernel. This can be a dangerous event if the process able to trigger request_module() is able to control either the modprobe binary or the module binary. This patch adds a new security hook to request_module() which can be used by an LSM to control a processes ability to call request_module(). Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-08-10security: define round_hint_to_min in !CONFIG_SECURITYEric Paris
Fix the header files to define round_hint_to_min() and to define mmap_min_addr_handler() in the !CONFIG_SECURITY case. Built and tested with !CONFIG_SECURITY Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-08-06Security/SELinux: seperate lsm specific mmap_min_addrEric Paris
Currently SELinux enforcement of controls on the ability to map low memory is determined by the mmap_min_addr tunable. This patch causes SELinux to ignore the tunable and instead use a seperate Kconfig option specific to how much space the LSM should protect. The tunable will now only control the need for CAP_SYS_RAWIO and SELinux permissions will always protect the amount of low memory designated by CONFIG_LSM_MMAP_MIN_ADDR. This allows users who need to disable the mmap_min_addr controls (usual reason being they run WINE as a non-root user) to do so and still have SELinux controls preventing confined domains (like a web server) from being able to map some area of low memory. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-08-06Capabilities: move cap_file_mmap to commoncap.cEric Paris
Currently we duplicate the mmap_min_addr test in cap_file_mmap and in security_file_mmap if !CONFIG_SECURITY. This patch moves cap_file_mmap into commoncap.c and then calls that function directly from security_file_mmap ifndef CONFIG_SECURITY like all of the other capability checks are done. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-06-25security: rename ptrace_may_access => ptrace_access_checkIngo Molnar
The ->ptrace_may_access() methods are named confusingly - the real ptrace_may_access() returns a bool, while these security checks have a retval convention. Rename it to ptrace_access_check, to reduce the confusion factor. [ Impact: cleanup, no code changed ] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: James Morris <jmorris@namei.org>