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* SELinux: memory leak in security_context_to_sid_coreEric Paris2008-09-041-3/+3
| | | | | | | | | | | | | | | | Fix a bug and a philosophical decision about who handles errors. security_context_to_sid_core() was leaking a context in the common case. This was causing problems on fedora systems which recently have started making extensive use of this function. In discussion it was decided that if string_to_context_struct() had an error it was its own responsibility to clean up any mess it created along the way. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* devcgroup: fix race against rmdir()Li Zefan2008-09-021-9/+9
| | | | | | | | | | | | | | | | During the use of a dev_cgroup, we should guarantee the corresponding cgroup won't be deleted (i.e. via rmdir). This can be done through css_get(&dev_cgroup->css), but here we can just get and use the dev_cgroup under rcu_read_lock. And also remove checking NULL dev_cgroup, it won't be NULL since a task always belongs to a cgroup. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Paul Menage <menage@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* security: Fix setting of PF_SUPERPRIV by __capable()David Howells2008-08-146-34/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the setting of PF_SUPERPRIV by __capable() as it could corrupt the flags the target process if that is not the current process and it is trying to change its own flags in a different way at the same time. __capable() is using neither atomic ops nor locking to protect t->flags. This patch removes __capable() and introduces has_capability() that doesn't set PF_SUPERPRIV on the process being queried. This patch further splits security_ptrace() in two: (1) security_ptrace_may_access(). This passes judgement on whether one process may access another only (PTRACE_MODE_ATTACH for ptrace() and PTRACE_MODE_READ for /proc), and takes a pointer to the child process. current is the parent. (2) security_ptrace_traceme(). This passes judgement on PTRACE_TRACEME only, and takes only a pointer to the parent process. current is the child. In Smack and commoncap, this uses has_capability() to determine whether the parent will be permitted to use PTRACE_ATTACH if normal checks fail. This does not set PF_SUPERPRIV. Two of the instances of __capable() actually only act on current, and so have been changed to calls to capable(). Of the places that were using __capable(): (1) The OOM killer calls __capable() thrice when weighing the killability of a process. All of these now use has_capability(). (2) cap_ptrace() and smack_ptrace() were using __capable() to check to see whether the parent was allowed to trace any process. As mentioned above, these have been split. For PTRACE_ATTACH and /proc, capable() is now used, and for PTRACE_TRACEME, has_capability() is used. (3) cap_safe_nice() only ever saw current, so now uses capable(). (4) smack_setprocattr() rejected accesses to tasks other than current just after calling __capable(), so the order of these two tests have been switched and capable() is used instead. (5) In smack_file_send_sigiotask(), we need to allow privileged processes to receive SIGIO on files they're manipulating. (6) In smack_task_wait(), we let a process wait for a privileged process, whether or not the process doing the waiting is privileged. I've tested this with the LTP SELinux and syscalls testscripts. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Andrew G. Morgan <morgan@kernel.org> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: /proc/mounts should show what it canEric Paris2008-07-301-1/+5
| | | | | | | | | | | | | | | | | | | | Given a hosed SELinux config in which a system never loads policy or disables SELinux we currently just return -EINVAL for anyone trying to read /proc/mounts. This is a configuration problem but we can certainly be more graceful. This patch just ignores -EINVAL when displaying LSM options and causes /proc/mounts display everything else it can. If policy isn't loaded the obviously there are no options, so we aren't really loosing any information here. This is safe as the only other return of EINVAL comes from security_sid_to_context_core() in the case of an invalid sid. Even if a FS was mounted with a now invalidated context that sid should have been remapped to unlabeled and so we won't hit the EINVAL and will work like we should. (yes, I tested to make sure it worked like I thought) Signed-off-by: Eric Paris <eparis@redhat.com> Tested-by: Marc Dionne <marc.c.dionne@gmail.com> Signed-off-by: James Morris <jmorris@namei.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2008-07-264-9/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (39 commits) [PATCH] fix RLIM_NOFILE handling [PATCH] get rid of corner case in dup3() entirely [PATCH] remove remaining namei_{32,64}.h crap [PATCH] get rid of indirect users of namei.h [PATCH] get rid of __user_path_lookup_open [PATCH] f_count may wrap around [PATCH] dup3 fix [PATCH] don't pass nameidata to __ncp_lookup_validate() [PATCH] don't pass nameidata to gfs2_lookupi() [PATCH] new (local) helper: user_path_parent() [PATCH] sanitize __user_walk_fd() et.al. [PATCH] preparation to __user_walk_fd cleanup [PATCH] kill nameidata passing to permission(), rename to inode_permission() [PATCH] take noexec checks to very few callers that care Re: [PATCH 3/6] vfs: open_exec cleanup [patch 4/4] vfs: immutable inode checking cleanup [patch 3/4] fat: dont call notify_change [patch 2/4] vfs: utimes cleanup [patch 1/4] vfs: utimes: move owner check into inode_change_ok() [PATCH] vfs: use kstrdup() and check failing allocation ...
| * [patch 3/4] fat: dont call notify_changeMiklos Szeredi2008-07-261-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The FAT_IOCTL_SET_ATTRIBUTES ioctl() calls notify_change() to change the file mode before changing the inode attributes. Replace with explicit calls to security_inode_setattr(), fat_setattr() and fsnotify_change(). This is equivalent to the original. The reason it is needed, is that later in the series we move the immutable check into notify_change(). That would break the FAT_IOCTL_SET_ATTRIBUTES ioctl, as it needs to perform the mode change regardless of the immutability of the file. [Fix error if fat is built as a module. Thanks to OGAWA Hirofumi for noticing.] Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * [PATCH] pass MAY_OPEN to vfs_permission() explicitlyAl Viro2008-07-264-9/+6
| | | | | | | | | | | | | | ... and get rid of the last "let's deduce mask from nameidata->flags" bit. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds2008-07-261-19/+8
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: netns: fix ip_rt_frag_needed rt_is_expired netfilter: nf_conntrack_extend: avoid unnecessary "ct->ext" dereferences netfilter: fix double-free and use-after free netfilter: arptables in netns for real netfilter: ip{,6}tables_security: fix future section mismatch selinux: use nf_register_hooks() netfilter: ebtables: use nf_register_hooks() Revert "pkt_sched: sch_sfq: dump a real number of flows" qeth: use dev->ml_priv instead of dev->priv syncookies: Make sure ECN is disabled net: drop unused BUG_TRAP() net: convert BUG_TRAP to generic WARN_ON drivers/net: convert BUG_TRAP to generic WARN_ON
| * selinux: use nf_register_hooks()Alexey Dobriyan2008-07-261-19/+8
| | | | | | | | | | | | | | Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tracehook: tracehook_tracer_taskRoland McGrath2008-07-261-19/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | This adds the tracehook_tracer_task() hook to consolidate all forms of "Who is using ptrace on me?" logic. This is used for "TracerPid:" in /proc and for permission checks. We also clean up the selinux code the called an identical accessor. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Reviewed-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | devcgroup: code cleanupLi Zefan2008-07-251-14/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - clean up set_majmin() - use simple_strtoul() to parse major/minor [akpm@linux-foundation.org: fix simple_strtoul() usage] [kosaki.motohiro@jp.fujitsu.com: fix warnings] Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | devcgroup: relax white-list protection down to RCUPavel Emelyanov2008-07-251-13/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently this list is protected with a simple spinlock, even for reading from one. This is OK, but can be better. Actually I want it to be better very much, since after replacing the OpenVZ device permissions engine with the cgroup-based one I noticed, that we set 12 default device permissions for each newly created container (for /dev/null, full, terminals, ect devices), and people sometimes have up to 20 perms more, so traversing the ~30-40 elements list under a spinlock doesn't seem very good. Here's the RCU protection for white-list - dev_whitelist_item-s are added and removed under the devcg->lock, but are looked up in permissions checking under the rcu_read_lock. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Menage <menage@google.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | cgroup files: convert devcgroup_access_write() into a cgroup write_string() ↵Paul Menage2008-07-251-63/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | handler This patch converts devcgroup_access_write() from a raw file handler into a handler for the cgroup write_string() method. This allows some boilerplate copying/locking/checking to be removed and simplifies the cleanup path, since these functions are performed by the cgroups framework before calling the handler. Signed-off-by: Paul Menage <menage@google.com> Cc: Paul Jackson <pj@sgi.com> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: Balbir Singh <balbir@in.ibm.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | security: filesystem capabilities no longer experimentalAndrew G. Morgan2008-07-241-2/+1
| | | | | | | | | | | | | | | | | | | | Filesystem capabilities have come of age. Remove the experimental tag for configuring filesystem capabilities. Signed-off-by: Andrew G. Morgan <morgan@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | security: protect legacy applications from executing with insufficient privilegeAndrew G. Morgan2008-07-241-49/+59
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | When cap_bset suppresses some of the forced (fP) capabilities of a file, it is generally only safe to execute the program if it understands how to recognize it doesn't have enough privilege to work correctly. For legacy applications (fE!=0), which have no non-destructive way to determine that they are missing privilege, we fail to execute (EPERM) any executable that requires fP capabilities, but would otherwise get pP' < fP. This is a fail-safe permission check. For some discussion of why it is problematic for (legacy) privileged applications to run with less than the set of capabilities requested for them, see: http://userweb.kernel.org/~morgan/sendmail-capabilities-war-story.html With this iteration of this support, we do not include setuid-0 based privilege protection from the bounding set. That is, the admin can still (ab)use the bounding set to suppress the privileges of a setuid-0 program. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: cleanup] Signed-off-by: Andrew G. Morgan <morgan@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Revert "SELinux: allow fstype unknown to policy to use xattrs if present"James Morris2008-07-153-37/+14
| | | | | | | | | This reverts commit 811f3799279e567aa354c649ce22688d949ac7a9. From Eric Paris: "Please drop this patch for now. It deadlocks on ntfs-3g. I need to rework it to handle fuse filesystems better. (casey was right)"
* security: remove register_security hookJames Morris2008-07-145-95/+5
| | | | | | | | | | The register security hook is no longer required, as the capability module is always registered. LSMs wishing to stack capability as a secondary module should do so explicitly. Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
* security: remove dummy module fixMiklos Szeredi2008-07-141-1/+1
| | | | | | | | Fix small oversight in "security: remove dummy module": CONFIG_SECURITY_FILE_CAPABILITIES doesn't depend on CONFIG_SECURITY Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: James Morris <jmorris@namei.org>
* security: remove dummy moduleMiklos Szeredi2008-07-145-1340/+996
| | | | | | | | | | Remove the dummy module and make the "capability" module the default. Compile and boot tested. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* security: remove unused sb_get_mnt_opts hookMiklos Szeredi2008-07-143-15/+0
| | | | | | | | The sb_get_mnt_opts() hook is unused, and is superseded by the sb_show_options() hook. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: James Morris <jmorris@namei.org>
* LSM/SELinux: show LSM mount options in /proc/mountsEric Paris2008-07-143-1/+65
| | | | | | | | | | | This patch causes SELinux mount options to show up in /proc/mounts. As with other code in the area seq_put errors are ignored. Other LSM's will not have their mount options displayed until they fill in their own security_sb_show_options() function. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: allow fstype unknown to policy to use xattrs if presentEric Paris2008-07-143-14/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently if a FS is mounted for which SELinux policy does not define an fs_use_* that FS will either be genfs labeled or not labeled at all. This decision is based on the existence of a genfscon rule in policy and is irrespective of the capabilities of the filesystem itself. This patch allows the kernel to check if the filesystem supports security xattrs and if so will use those if there is no fs_use_* rule in policy. An fstype with a no fs_use_* rule but with a genfs rule will use xattrs if available and will follow the genfs rule. This can be particularly interesting for things like ecryptfs which actually overlays a real underlying FS. If we define excryptfs in policy to use xattrs we will likely get this wrong at times, so with this path we just don't need to define it! Overlay ecryptfs on top of NFS with no xattr support: SELinux: initialized (dev ecryptfs, type ecryptfs), uses genfs_contexts Overlay ecryptfs on top of ext4 with xattr support: SELinux: initialized (dev ecryptfs, type ecryptfs), uses xattr It is also useful as the kernel adds new FS we don't need to add them in policy if they support xattrs and that is how we want to handle them. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* security: fix return of void-valued expressionsJames Morris2008-07-141-3/+3
| | | | | | | | | Fix several warnings generated by sparse of the form "returning void-valued expression". Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Serge Hallyn <serue@us.ibm.com>
* SELinux: use do_each_thread as a proper do/while blockJames Morris2008-07-141-2/+2
| | | | | | | Use do_each_thread as a proper do/while block. Sparse complained. Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
* SELinux: remove unused and shadowed addrlen variableJames Morris2008-07-141-3/+1
| | | | | | | | Remove unused and shadowed addrlen variable. Picked up by sparse. Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Paul Moore <paul.moore@hp.com>
* SELinux: more user friendly unknown handling printkEric Paris2008-07-142-5/+7
| | | | | | | | | | | | I've gotten complaints and reports about people not understanding the meaning of the current unknown class/perm handling the kernel emits on every policy load. Hopefully this will make make it clear to everyone the meaning of the message and won't waste a printk the user won't care about anyway on systems where the kernel and the policy agree on everything. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* selinux: change handling of invalid classes (Was: Re: 2.6.26-rc5-mm1 selinux ↵Stephen Smalley2008-07-141-3/+13
| | | | | | | | | | | | | | | | | | | | | | whine) On Mon, 2008-06-09 at 01:24 -0700, Andrew Morton wrote: > Getting a few of these with FC5: > > SELinux: context_struct_compute_av: unrecognized class 69 > SELinux: context_struct_compute_av: unrecognized class 69 > > one came out when I logged in. > > No other symptoms, yet. Change handling of invalid classes by SELinux, reporting class values unknown to the kernel as errors (w/ ratelimit applied) and handling class values unknown to policy as normal denials. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: drop load_mutex in security_load_policyEric Paris2008-07-141-13/+1
| | | | | | | | | | | We used to protect against races of policy load in security_load_policy by using the load_mutex. Since then we have added a new mutex, sel_mutex, in sel_write_load() which is always held across all calls to security_load_policy we are covered and can safely just drop this one. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: fix off by 1 reference of class_to_string in context_struct_compute_avEric Paris2008-07-141-1/+1
| | | | | | | | | | | | | | | | | | | | | The class_to_string array is referenced by tclass. My code mistakenly was using tclass - 1. If the proceeding class is a userspace class rather than kernel class this may cause a denial/EINVAL even if unknown handling is set to allow. The bug shouldn't be allowing excess privileges since those are given based on the contents of another array which should be correctly referenced. At this point in time its pretty unlikely this is going to cause problems. The most recently added kernel classes which could be affected are association, dccp_socket, and peer. Its pretty unlikely any policy with handle_unknown=allow doesn't have association and dccp_socket undefined (they've been around longer than unknown handling) and peer is conditionalized on a policy cap which should only be defined if that class exists in policy. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: open code sidtab lockJames Morris2008-07-141-11/+7
| | | | | | | Open code sidtab lock to make Andrew Morton happy. Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
* SELinux: open code load_mutexJames Morris2008-07-141-12/+9
| | | | | | Open code load_mutex as suggested by Andrew Morton. Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: open code policy_rwlockJames Morris2008-07-141-56/+52
| | | | | | | Open code policy_rwlock, as suggested by Andrew Morton. Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
* selinux: fix endianness bug in network node address handlingStephen Smalley2008-07-141-7/+8
| | | | | | | | | | | | | | | | | Fix an endianness bug in the handling of network node addresses by SELinux. This yields no change on little endian hardware but fixes the incorrect handling on big endian hardware. The network node addresses are stored in network order in memory by checkpolicy, not in cpu/host order, and thus should not have cpu_to_le32/le32_to_cpu conversions applied upon policy write/read unlike other data in the policy. Bug reported by John Weeks of Sun, who noticed that binary policy files built from the same policy source on x86 and sparc differed and tracked it down to the ipv4 address handling in checkpolicy. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* selinux: simplify ioctl checkingStephen Smalley2008-07-141-40/+8
| | | | | | | | | | | Simplify and improve the robustness of the SELinux ioctl checking by using the "access mode" bits of the ioctl command to determine the permission check rather than dealing with individual command values. This removes any knowledge of specific ioctl commands from SELinux and follows the same guidance we gave to Smack earlier. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: enable processes with mac_admin to get the raw inode contextsStephen Smalley2008-07-141-4/+23
| | | | | | | | | | | Enable processes with CAP_MAC_ADMIN + mac_admin permission in policy to get undefined contexts on inodes. This extends the support for deferred mapping of security contexts in order to permit restorecon and similar programs to see the raw file contexts unknown to the system policy in order to check them. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* Security: split proc ptrace checking into read vs. attachStephen Smalley2008-07-145-8/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enable security modules to distinguish reading of process state via proc from full ptrace access by renaming ptrace_may_attach to ptrace_may_access and adding a mode argument indicating whether only read access or full attach access is requested. This allows security modules to permit access to reading process state without granting full ptrace access. The base DAC/capability checking remains unchanged. Read access to /proc/pid/mem continues to apply a full ptrace attach check since check_mem_permission() already requires the current task to already be ptracing the target. The other ptrace checks within proc for elements like environ, maps, and fds are changed to pass the read mode instead of attach. In the SELinux case, we model such reading of process state as a reading of a proc file labeled with the target process' label. This enables SELinux policy to permit such reading of process state without permitting control or manipulation of the target process, as there are a number of cases where programs probe for such information via proc but do not need to be able to control the target (e.g. procps, lsof, PolicyKit, ConsoleKit). At present we have to choose between allowing full ptrace in policy (more permissive than required/desired) or breaking functionality (or in some cases just silencing the denials via dontaudit rules but this can hide genuine attacks). This version of the patch incorporates comments from Casey Schaufler (change/replace existing ptrace_may_attach interface, pass access mode), and Chris Wright (provide greater consistency in the checking). Note that like their predecessors __ptrace_may_attach and ptrace_may_attach, the __ptrace_may_access and ptrace_may_access interfaces use different return value conventions from each other (0 or -errno vs. 1 or 0). I retained this difference to avoid any changes to the caller logic but made the difference clearer by changing the latter interface to return a bool rather than an int and by adding a comment about it to ptrace.h for any future callers. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: remove inherit field from inode_security_structJames Morris2008-07-141-1/+0
| | | | | | | Remove inherit field from inode_security_struct, per Stephen Smalley: "Let's just drop inherit altogether - dead field." Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: reorder inode_security_struct to increase objs/slab on 64bitRichard Kennedy2008-07-141-1/+1
| | | | | | | | | reorder inode_security_struct to remove padding on 64 bit builds size reduced from 72 to 64 bytes increasing objects per slab to 64. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: keep the code clean formating and syntaxEric Paris2008-07-149-30/+35
| | | | | | | | | | | | | | | Formatting and syntax changes whitespace, tabs to spaces, trailing space put open { on same line as struct def remove unneeded {} after if statements change printk("Lu") to printk("llu") convert asm/uaccess.h to linux/uaacess.h includes remove unnecessary asm/bug.h includes convert all users of simple_strtol to strict_strtol Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: fix sleeping allocation in security_context_to_sidStephen Smalley2008-07-141-30/+40
| | | | | | | | Fix a sleeping function called from invalid context bug by moving allocation to the callers prior to taking the policy rdlock. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* selinux: support deferred mapping of contextsStephen Smalley2008-07-148-128/+248
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce SELinux support for deferred mapping of security contexts in the SID table upon policy reload, and use this support for inode security contexts when the context is not yet valid under the current policy. Only processes with CAP_MAC_ADMIN + mac_admin permission in policy can set undefined security contexts on inodes. Inodes with such undefined contexts are treated as having the unlabeled context until the context becomes valid upon a policy reload that defines the context. Context invalidation upon policy reload also uses this support to save the context information in the SID table and later recover it upon a subsequent policy reload that defines the context again. This support is to enable package managers and similar programs to set down file contexts unknown to the system policy at the time the file is created in order to better support placing loadable policy modules in packages and to support build systems that need to create images of different distro releases with different policies w/o requiring all of the contexts to be defined or legal in the build host policy. With this patch applied, the following sequence is possible, although in practice it is recommended that this permission only be allowed to specific program domains such as the package manager. # rmdir baz # rm bar # touch bar # chcon -t foo_exec_t bar # foo_exec_t is not yet defined chcon: failed to change context of `bar' to `system_u:object_r:foo_exec_t': Invalid argument # mkdir -Z system_u:object_r:foo_exec_t baz mkdir: failed to set default file creation context to `system_u:object_r:foo_exec_t': Invalid argument # cat setundefined.te policy_module(setundefined, 1.0) require { type unconfined_t; type unlabeled_t; } files_type(unlabeled_t) allow unconfined_t self:capability2 mac_admin; # make -f /usr/share/selinux/devel/Makefile setundefined.pp # semodule -i setundefined.pp # chcon -t foo_exec_t bar # foo_exec_t is not yet defined # mkdir -Z system_u:object_r:foo_exec_t baz # ls -Zd bar baz -rw-r--r-- root root system_u:object_r:unlabeled_t bar drwxr-xr-x root root system_u:object_r:unlabeled_t baz # cat foo.te policy_module(foo, 1.0) type foo_exec_t; files_type(foo_exec_t) # make -f /usr/share/selinux/devel/Makefile foo.pp # semodule -i foo.pp # defines foo_exec_t # ls -Zd bar baz -rw-r--r-- root root user_u:object_r:foo_exec_t bar drwxr-xr-x root root system_u:object_r:foo_exec_t baz # semodule -r foo # ls -Zd bar baz -rw-r--r-- root root system_u:object_r:unlabeled_t bar drwxr-xr-x root root system_u:object_r:unlabeled_t baz # semodule -i foo.pp # ls -Zd bar baz -rw-r--r-- root root user_u:object_r:foo_exec_t bar drwxr-xr-x root root system_u:object_r:foo_exec_t baz # semodule -r setundefined foo # chcon -t foo_exec_t bar # no longer defined and not allowed chcon: failed to change context of `bar' to `system_u:object_r:foo_exec_t': Invalid argument # rmdir baz # mkdir -Z system_u:object_r:foo_exec_t baz mkdir: failed to set default file creation context to `system_u:object_r:foo_exec_t': Invalid argument Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* devcgroup: fix permission check when adding entry to child cgroupLi Zefan2008-07-131-1/+1
| | | | | | | | | | | | | | | | | | | # cat devices.list c 1:3 r # echo 'c 1:3 w' > sub/devices.allow # cat sub/devices.list c 1:3 w As illustrated, the parent group has no write permission to /dev/null, so it's child should not be allowed to add this write permission. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* devcgroup: always show positive major/minor numLi Zefan2008-07-131-2/+2
| | | | | | | | | | | | | | | | | # echo "b $((0x7fffffff)):$((0x80000000)) rwm" > devices.allow # cat devices.list b 214748364:-21474836 rwm though a major/minor number of 0x800000000 is meaningless, we should not cast it to a negative value. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* devcgroup: fix odd behaviour when writing 'a' to devices.allowLi Zefan2008-07-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | # cat /devcg/devices.list a *:* rwm # echo a > devices.allow # cat /devcg/devices.list a *:* rwm a 0:0 rwm This is odd and maybe confusing. With this patch, writing 'a' to devices.allow will add 'a *:* rwm' to the whitelist. Also a few fixes and updates to the document. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* security: filesystem capabilities: fix CAP_SETPCAP handlingAndrew G. Morgan2008-07-041-3/+10
| | | | | | | | | | | | | The filesystem capability support meaning for CAP_SETPCAP is less powerful than the non-filesystem capability support. As such, when filesystem capabilities are configured, we should not permit CAP_SETPCAP to 'enhance' the current process through strace manipulation of a child process. Signed-off-by: Andrew G. Morgan <morgan@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* capabilities: add (back) dummy support for KEEPCAPSAndrew G. Morgan2008-06-121-1/+23
| | | | | | | | | | | | | | | | | | | | The dummy module is used by folk that run security conscious code(!?). A feature of such code (for example, dhclient) is that it tries to operate with minimum privilege (dropping unneeded capabilities). While the dummy module doesn't restrict code execution based on capability state, the user code expects the kernel to appear to support it. This patch adds back faked support for the PR_SET_KEEPCAPS etc., calls - making the kernel behave as before 2.6.26. For details see: http://bugzilla.kernel.org/show_bug.cgi?id=10748 Signed-off-by: Andrew G. Morgan <morgan@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* keys: remove unused key_alloc_semDaniel Walker2008-06-061-1/+0
| | | | | | | | | This semaphore doesn't appear to be used, so remove it. Signed-off-by: Daniel Walker <dwalker@mvista.com> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* devscgroup: make white list more compact in some casesPavel Emelyanov2008-06-061-2/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | Consider you added a 'c foo:bar r' permission to some cgroup and then (a bit later) 'c'foo:bar w' for it. After this you'll see the c foo:bar r c foo:bar w lines in a devices.list file. Another example - consider you added 10 'c foo:bar r' permissions to some cgroup (e.g. by mistake). After this you'll see 10 c foo:bar r lines in a list file. This is weird. This situation also has one more annoying consequence. Having many items in a white list makes permissions checking slower, sine it has to walk a longer list. The proposal is to merge permissions for items, that correspond to the same device. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* devscgroup: relax task to dev_cgroup conversionPavel Emelyanov2008-06-061-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Two functions, that need to get a device_cgroup from a task (they are devcgroup_inode_permission and devcgroup_inode_mknod) make it in a strange way: They get a css_set from task, then a subsys_state from css_set, then a cgroup from the state and then a subsys_state again from the cgroup. Besides, the devices_subsys_id is read from memory, whilst there's a enum-ed constant for it. Optimize this part a bit: 1. Get the subsys_stats form the task and be done - no 2 extra dereferences, 2. Use the device_subsys_id constant, not the value from memory (i.e. one less dereference). Found while preparing 2.6.26 OpenVZ port. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Paul Menage <menage@google.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* devcgroup: make a helper to convert cgroup_subsys_state to devs_cgroupPavel Emelyanov2008-06-061-2/+6
| | | | | | | | | | | | | | | | | This is just picking the container_of out of cgroup_to_devcgroup into a separate function. This new css_to_devcgroup will be used in the 2nd patch. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>