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2012-05-31security/keys/keyctl.c: suppress memory allocation failure warningAndrew Morton1-1/+1
This allocation may be large. The code is probing to see if it will succeed and if not, it falls back to vmalloc(). We should suppress any page-allocation failure messages when the fallback happens. Reported-by: Dave Jones <davej@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-23Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespaceLinus Torvalds3-4/+5
Pull user namespace enhancements from Eric Biederman: "This is a course correction for the user namespace, so that we can reach an inexpensive, maintainable, and reasonably complete implementation. Highlights: - Config guards make it impossible to enable the user namespace and code that has not been converted to be user namespace safe. - Use of the new kuid_t type ensures the if you somehow get past the config guards the kernel will encounter type errors if you enable user namespaces and attempt to compile in code whose permission checks have not been updated to be user namespace safe. - All uids from child user namespaces are mapped into the initial user namespace before they are processed. Removing the need to add an additional check to see if the user namespace of the compared uids remains the same. - With the user namespaces compiled out the performance is as good or better than it is today. - For most operations absolutely nothing changes performance or operationally with the user namespace enabled. - The worst case performance I could come up with was timing 1 billion cache cold stat operations with the user namespace code enabled. This went from 156s to 164s on my laptop (or 156ns to 164ns per stat operation). - (uid_t)-1 and (gid_t)-1 are reserved as an internal error value. Most uid/gid setting system calls treat these value specially anyway so attempting to use -1 as a uid would likely cause entertaining failures in userspace. - If setuid is called with a uid that can not be mapped setuid fails. I have looked at sendmail, login, ssh and every other program I could think of that would call setuid and they all check for and handle the case where setuid fails. - If stat or a similar system call is called from a context in which we can not map a uid we lie and return overflowuid. The LFS experience suggests not lying and returning an error code might be better, but the historical precedent with uids is different and I can not think of anything that would break by lying about a uid we can't map. - Capabilities are localized to the current user namespace making it safe to give the initial user in a user namespace all capabilities. My git tree covers all of the modifications needed to convert the core kernel and enough changes to make a system bootable to runlevel 1." Fix up trivial conflicts due to nearby independent changes in fs/stat.c * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits) userns: Silence silly gcc warning. cred: use correct cred accessor with regards to rcu read lock userns: Convert the move_pages, and migrate_pages permission checks to use uid_eq userns: Convert cgroup permission checks to use uid_eq userns: Convert tmpfs to use kuid and kgid where appropriate userns: Convert sysfs to use kgid/kuid where appropriate userns: Convert sysctl permission checks to use kuid and kgids. userns: Convert proc to use kuid/kgid where appropriate userns: Convert ext4 to user kuid/kgid where appropriate userns: Convert ext3 to use kuid/kgid where appropriate userns: Convert ext2 to use kuid/kgid where appropriate. userns: Convert devpts to use kuid/kgid where appropriate userns: Convert binary formats to use kuid/kgid where appropriate userns: Add negative depends on entries to avoid building code that is userns unsafe userns: signal remove unnecessary map_cred_ns userns: Teach inode_capable to understand inodes whose uids map to other namespaces. userns: Fail exec for suid and sgid binaries with ids outside our user namespace. userns: Convert stat to return values mapped from kuids and kgids userns: Convert user specfied uids and gids in chown into kuids and kgid userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs ...
2012-05-16KEYS: Don't check for NULL key pointer in key_validate()David Howells1-24/+16
Don't bother checking for NULL key pointer in key_validate() as all of the places that call it will crash anyway if the relevant key pointer is NULL by the time they call key_validate(). Therefore, the checking must be done prior to calling here. Whilst we're at it, simplify the key_validate() function a bit and mark its argument const. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-05-11KEYS: Add invalidation supportDavid Howells8-28/+110
Add support for invalidating a key - which renders it immediately invisible to further searches and causes the garbage collector to immediately wake up, remove it from keyrings and then destroy it when it's no longer referenced. It's better not to do this with keyctl_revoke() as that marks the key to start returning -EKEYREVOKED to searches when what is actually desired is to have the key refetched. To invalidate a key the caller must be granted SEARCH permission by the key. This may be too strict. It may be better to also permit invalidation if the caller has any of READ, WRITE or SETATTR permission. The primary use for this is to evict keys that are cached in special keyrings, such as the DNS resolver or an ID mapper. Signed-off-by: David Howells <dhowells@redhat.com>
2012-05-11KEYS: Do LRU discard in full keyringsDavid Howells2-7/+42
Do an LRU discard in keyrings that are full rather than returning ENFILE. To perform this, a time_t is added to the key struct and updated by the creation of a link to a key and by a key being found as the result of a search. At the completion of a successful search, the keyrings in the path between the root of the search and the first found link to it also have their last-used times updated. Note that discarding a link to a key from a keyring does not necessarily destroy the key as there may be references held by other places. An alternate discard method that might suffice is to perform FIFO discard from the keyring, using the spare 2-byte hole in the keylist header as the index of the next link to be discarded. This is useful when using a keyring as a cache for DNS results or foreign filesystem IDs. This can be tested by the following. As root do: echo 1000 >/proc/sys/kernel/keys/root_maxkeys kr=`keyctl newring foo @s` for ((i=0; i<2000; i++)); do keyctl add user a$i a $kr; done Without this patch ENFILE should be reported when the keyring fills up. With this patch, the keyring discards keys in an LRU fashion. Note that the stored LRU time has a granularity of 1s. After doing this, /proc/key-users can be observed and should show that most of the 2000 keys have been discarded: [root@andromeda ~]# cat /proc/key-users 0: 517 516/516 513/1000 5249/20000 The "513/1000" here is the number of quota-accounted keys present for this user out of the maximum permitted. In /proc/keys, the keyring shows the number of keys it has and the number of slots it has allocated: [root@andromeda ~]# grep foo /proc/keys 200c64c4 I--Q-- 1 perm 3b3f0000 0 0 keyring foo: 509/509 The maximum is (PAGE_SIZE - header) / key pointer size. That's typically 509 on a 64-bit system and 1020 on a 32-bit system. Signed-off-by: David Howells <dhowells@redhat.com>
2012-05-11KEYS: Permit in-place link replacement in keyring listDavid Howells2-40/+57
Make use of the previous patch that makes the garbage collector perform RCU synchronisation before destroying defunct keys. Key pointers can now be replaced in-place without creating a new keyring payload and replacing the whole thing as the discarded keys will not be destroyed until all currently held RCU read locks are released. If the keyring payload space needs to be expanded or contracted, then a replacement will still need allocating, and the original will still have to be freed by RCU. Signed-off-by: David Howells <dhowells@redhat.com>
2012-05-11KEYS: Perform RCU synchronisation on keys prior to key destructionDavid Howells1-29/+44
Make the keys garbage collector invoke synchronize_rcu() prior to destroying keys with a zero usage count. This means that a key can be examined under the RCU read lock in the safe knowledge that it won't get deallocated until after the lock is released - even if its usage count becomes zero whilst we're looking at it. This is useful in keyring search vs key link. Consider a keyring containing a link to a key. That link can be replaced in-place in the keyring without requiring an RCU copy-and-replace on the keyring contents without breaking a search underway on that keyring when the displaced key is released, provided the key is actually destroyed only after the RCU read lock held by the search algorithm is released. This permits __key_link() to replace a key without having to reallocate the key payload. A key gets replaced if a new key being linked into a keyring has the same type and description. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@redhat.com>
2012-05-11KEYS: Announce key type (un)registrationDavid Howells1-0/+3
Announce the (un)registration of a key type in the core key code rather than in the callers. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Mimi Zohar <zohar@us.ibm.com>
2012-05-11KEYS: Reorganise keys MakefileDavid Howells1-3/+9
Reorganise the keys directory Makefile to put all the core bits together and the type-specific bits after. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Mimi Zohar <zohar@us.ibm.com>
2012-05-11KEYS: Move the key config into security/keys/KconfigDavid Howells1-0/+71
Move the key config into security/keys/Kconfig as there are going to be a lot of key-related options. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Mimi Zohar <zohar@us.ibm.com>
2012-05-03userns: Convert group_info values from gid_t to kgid_t.Eric W. Biederman1-1/+2
As a first step to converting struct cred to be all kuid_t and kgid_t values convert the group values stored in group_info to always be kgid_t values. Unless user namespaces are used this change should have no effect. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-04-07cred: Refcount the user_ns pointed to by the cred.Eric W. Biederman1-1/+1
struct user_struct will shortly loose it's user_ns reference so make the cred user_ns reference a proper reference complete with reference counting. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-04-07userns: Use cred->user_ns instead of cred->user->user_nsEric W. Biederman3-3/+3
Optimize performance and prepare for the removal of the user_ns reference from user_struct. Remove the slow long walk through cred->user->user_ns and instead go straight to cred->user_ns. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-03-23usermodehelper: kill umh_wait, renumber UMH_* constantsOleg Nesterov1-1/+1
No functional changes. It is not sane to use UMH_KILLABLE with enum umh_wait, but obviously we do not want another argument in call_usermodehelper_* helpers. Kill this enum, use the plain int. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tejun Heo <tj@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23Merge tag 'nfs-for-3.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds2-16/+22
Pull NFS client updates for Linux 3.4 from Trond Myklebust: "New features include: - Add NFS client support for containers. This should enable most of the necessary functionality, including lockd support, and support for rpc.statd, NFSv4 idmapper and RPCSEC_GSS upcalls into the correct network namespace from which the mount system call was issued. - NFSv4 idmapper scalability improvements Base the idmapper cache on the keyring interface to allow concurrent access to idmapper entries. Start the process of migrating users from the single-threaded daemon-based approach to the multi-threaded request-key based approach. - NFSv4.1 implementation id. Allows the NFSv4.1 client and server to mutually identify each other for logging and debugging purposes. - Support the 'vers=4.1' mount option for mounting NFSv4.1 instead of having to use the more counterintuitive 'vers=4,minorversion=1'. - SUNRPC tracepoints. Start the process of adding tracepoints in order to improve debugging of the RPC layer. - pNFS object layout support for autologin. Important bugfixes include: - Fix a bug in rpc_wake_up/rpc_wake_up_status that caused them to fail to wake up all tasks when applied to priority waitqueues. - Ensure that we handle read delegations correctly, when we try to truncate a file. - A number of fixes for NFSv4 state manager loops (mostly to do with delegation recovery)." * tag 'nfs-for-3.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (224 commits) NFS: fix sb->s_id in nfs debug prints xprtrdma: Remove assumption that each segment is <= PAGE_SIZE xprtrdma: The transport should not bug-check when a dup reply is received pnfs-obj: autologin: Add support for protocol autologin NFS: Remove nfs4_setup_sequence from generic rename code NFS: Remove nfs4_setup_sequence from generic unlink code NFS: Remove nfs4_setup_sequence from generic read code NFS: Remove nfs4_setup_sequence from generic write code NFS: Fix more NFS debug related build warnings SUNRPC/LOCKD: Fix build warnings when CONFIG_SUNRPC_DEBUG is undefined nfs: non void functions must return a value SUNRPC: Kill compiler warning when RPC_DEBUG is unset SUNRPC/NFS: Add Kbuild dependencies for NFS_DEBUG/RPC_DEBUG NFS: Use cond_resched_lock() to reduce latencies in the commit scans NFSv4: It is not safe to dereference lsp->ls_state in release_lockowner NFS: ncommit count is being double decremented SUNRPC: We must not use list_for_each_entry_safe() in rpc_wake_up() Try using machine credentials for RENEW calls NFSv4.1: Fix a few issues in filelayout_commit_pagelist NFSv4.1: Clean ups and bugfixes for the pNFS read/writeback/commit code ...
2012-03-07KEYS: testing wrong bit for KEY_FLAG_REVOKEDDan Carpenter1-1/+2
The test for "if (cred->request_key_auth->flags & KEY_FLAG_REVOKED) {" should actually testing that the (1 << KEY_FLAG_REVOKED) bit is set. The current code actually checks for KEY_FLAG_DEAD. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-03-01Created a function for setting timeouts on keysBryan Schumaker2-16/+22
The keyctl_set_timeout function isn't exported to other parts of the kernel, but I want to use it for the NFS idmapper. I already have the key, but I wanted a generic way to set the timeout. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-09Merge branch 'next-queue' into nextJames Morris1-1/+14
2012-01-23Merge git://git.samba.org/sfrench/cifs-2.6Linus Torvalds3-0/+39
* git://git.samba.org/sfrench/cifs-2.6: CIFS: Rename *UCS* functions to *UTF16* [CIFS] ACL and FSCACHE support no longer EXPERIMENTAL [CIFS] Fix build break with multiuser patch when LANMAN disabled cifs: warn about impending deprecation of legacy MultiuserMount code cifs: fetch credentials out of keyring for non-krb5 auth multiuser mounts cifs: sanitize username handling keys: add a "logon" key type cifs: lower default wsize when unix extensions are not used cifs: better instrumentation for coalesce_t2 cifs: integer overflow in parse_dacl() cifs: Fix sparse warning when calling cifs_strtoUCS CIFS: Add descriptions to the brlock cache functions
2012-01-19keys: fix user_defined key sparse messagesMimi Zohar1-3/+3
Replace the rcu_assign_pointer() calls with rcu_assign_keypointer(). Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2012-01-19KEYS: Allow special keyrings to be clearedDavid Howells1-1/+14
The kernel contains some special internal keyrings, for instance the DNS resolver keyring : 2a93faf1 I----- 1 perm 1f030000 0 0 keyring .dns_resolver: empty It would occasionally be useful to allow the contents of such keyrings to be flushed by root (cache invalidation). Allow a flag to be set on a keyring to mark that someone possessing the sysadmin capability can clear the keyring, even without normal write access to the keyring. Set this flag on the special keyrings created by the DNS resolver, the NFS identity mapper and the CIFS identity mapper. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@redhat.com> Acked-by: Steve Dickson <steved@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2012-01-17keys: add a "logon" key typeJeff Layton3-0/+39
For CIFS, we want to be able to store NTLM credentials (aka username and password) in the keyring. We do not, however want to allow users to fetch those keys back out of the keyring since that would be a security risk. Unfortunately, due to the nuances of key permission bits, it's not possible to do this. We need to grant search permissions so the kernel can find these keys, but that also implies permissions to read the payload. Resolve this by adding a new key_type. This key type is essentially the same as key_type_user, but does not define a .read op. This prevents the payload from ever being visible from userspace. This key type also vets the description to ensure that it's "qualified" by checking to ensure that it has a ':' in it that is preceded by other characters. Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
2012-01-18encrypted-keys: fix rcu and sparse messagesMimi Zohar2-2/+2
Enabling CONFIG_PROVE_RCU and CONFIG_SPARSE_RCU_POINTER resulted in "suspicious rcu_dereference_check() usage!" and "incompatible types in comparison expression (different address spaces)" messages. Access the masterkey directly when holding the rwsem. Changelog v1: - Use either rcu_read_lock()/rcu_derefence_key()/rcu_read_unlock() or remove the unnecessary rcu_derefence() - David Howells Reported-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2012-01-18keys: fix trusted/encrypted keys sparse rcu_assign_pointer messagesMimi Zohar3-4/+6
Define rcu_assign_keypointer(), which uses the key payload.rcudata instead of payload.data, to resolve the CONFIG_SPARSE_RCU_POINTER message: "incompatible types in comparison expression (different address spaces)" Replace the rcu_assign_pointer() calls in encrypted/trusted keys with rcu_assign_keypointer(). Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2012-01-18KEYS: Add missing smp_rmb() primitives to the keyring search codeDavid Howells2-8/+18
Add missing smp_rmb() primitives to the keyring search code. When keyring payloads are appended to without replacement (thus using up spare slots in the key pointer array), an smp_wmb() is issued between the pointer assignment and the increment of the key count (nkeys). There should be corresponding read barriers between the read of nkeys and dereferences of keys[n] when n is dependent on the value of nkeys. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2012-01-09Merge branch 'next' into for-linusJames Morris1-0/+3
Conflicts: security/integrity/evm/evm_crypto.c Resolved upstream fix vs. next conflict manually. Signed-off-by: James Morris <jmorris@namei.org>
2011-11-17KEYS: Give key types their own lockdep class for key->semDavid Howells1-0/+3
Give keys their own lockdep class to differentiate them from each other in case a key of one type has to refer to a key of another type. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-11-16encrypted-keys: module build fixesMimi Zohar2-3/+8
Encrypted keys are encrypted/decrypted using either a trusted or user-defined key type, which is referred to as the 'master' key. The master key may be of type trusted iff the trusted key is builtin or both the trusted key and encrypted keys are built as modules. This patch resolves the build dependency problem. - Use "masterkey-$(CONFIG_TRUSTED_KEYS)-$(CONFIG_ENCRYPTED_KEYS)" construct to encapsulate the above logic. (Suggested by Dimtry Kasatkin.) - Fixing the encrypted-keys Makefile, results in a module name change from encrypted.ko to encrypted-keys.ko. - Add module dependency for request_trusted_key() definition Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-11-16encrypted-keys: fix error return codeMimi Zohar1-1/+1
Fix request_master_key() error return code. Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-11-15KEYS: Fix a NULL pointer deref in the user-defined key typeDavid Howells1-1/+2
Fix a NULL pointer deref in the user-defined key type whereby updating a negative key into a fully instantiated key will cause an oops to occur when the code attempts to free the non-existent old payload. This results in an oops that looks something like the following: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 IP: [<ffffffff81085fa1>] __call_rcu+0x11/0x13e PGD 3391d067 PUD 3894a067 PMD 0 Oops: 0002 [#1] SMP CPU 1 Pid: 4354, comm: keyctl Not tainted 3.1.0-fsdevel+ #1140 /DG965RY RIP: 0010:[<ffffffff81085fa1>] [<ffffffff81085fa1>] __call_rcu+0x11/0x13e RSP: 0018:ffff88003d591df8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000006e RDX: ffffffff8161d0c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88003d591e18 R08: 0000000000000000 R09: ffffffff8152fa6c R10: 0000000000000000 R11: 0000000000000300 R12: ffff88003b8f9538 R13: ffffffff8161d0c0 R14: ffff88003b8f9d50 R15: ffff88003c69f908 FS: 00007f97eb18c720(0000) GS:ffff88003bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 000000003d47a000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process keyctl (pid: 4354, threadinfo ffff88003d590000, task ffff88003c78a040) Stack: ffff88003e0ffde0 ffff88003b8f9538 0000000000000001 ffff88003b8f9d50 ffff88003d591e28 ffffffff810860f0 ffff88003d591e68 ffffffff8117bfea ffff88003d591e68 ffffffff00000000 ffff88003e0ffde1 ffff88003e0ffde0 Call Trace: [<ffffffff810860f0>] call_rcu_sched+0x10/0x12 [<ffffffff8117bfea>] user_update+0x8d/0xa2 [<ffffffff8117723a>] key_create_or_update+0x236/0x270 [<ffffffff811789b1>] sys_add_key+0x123/0x17e [<ffffffff813b84bb>] system_call_fastpath+0x16/0x1b Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@redhat.com> Acked-by: Neil Horman <nhorman@redhat.com> Acked-by: Steve Dickson <steved@redhat.com> Acked-by: James Morris <jmorris@namei.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31security: follow rename pack_hex_byte() to hex_byte_pack()Andy Shevchenko2-2/+2
There is no functional change. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Mimi Zohar <zohar@us.ibm.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31Cross Memory AttachChristopher Yeoh2-2/+2
The basic idea behind cross memory attach is to allow MPI programs doing intra-node communication to do a single copy of the message rather than a double copy of the message via shared memory. The following patch attempts to achieve this by allowing a destination process, given an address and size from a source process, to copy memory directly from the source process into its own address space via a system call. There is also a symmetrical ability to copy from the current process's address space into a destination process's address space. - Use of /proc/pid/mem has been considered, but there are issues with using it: - Does not allow for specifying iovecs for both src and dest, assuming preadv or pwritev was implemented either the area read from or written to would need to be contiguous. - Currently mem_read allows only processes who are currently ptrace'ing the target and are still able to ptrace the target to read from the target. This check could possibly be moved to the open call, but its not clear exactly what race this restriction is stopping (reason appears to have been lost) - Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix domain socket is a bit ugly from a userspace point of view, especially when you may have hundreds if not (eventually) thousands of processes that all need to do this with each other - Doesn't allow for some future use of the interface we would like to consider adding in the future (see below) - Interestingly reading from /proc/pid/mem currently actually involves two copies! (But this could be fixed pretty easily) As mentioned previously use of vmsplice instead was considered, but has problems. Since you need the reader and writer working co-operatively if the pipe is not drained then you block. Which requires some wrapping to do non blocking on the send side or polling on the receive. In all to all communication it requires ordering otherwise you can deadlock. And in the example of many MPI tasks writing to one MPI task vmsplice serialises the copying. There are some cases of MPI collectives where even a single copy interface does not get us the performance gain we could. For example in an MPI_Reduce rather than copy the data from the source we would like to instead use it directly in a mathops (say the reduce is doing a sum) as this would save us doing a copy. We don't need to keep a copy of the data from the source. I haven't implemented this, but I think this interface could in the future do all this through the use of the flags - eg could specify the math operation and type and the kernel rather than just copying the data would apply the specified operation between the source and destination and store it in the destination. Although we don't have a "second user" of the interface (though I've had some nibbles from people who may be interested in using it for intra process messaging which is not MPI). This interface is something which hardware vendors are already doing for their custom drivers to implement fast local communication. And so in addition to this being useful for OpenMPI it would mean the driver maintainers don't have to fix things up when the mm changes. There was some discussion about how much faster a true zero copy would go. Here's a link back to the email with some testing I did on that: http://marc.info/?l=linux-mm&m=130105930902915&w=2 There is a basic man page for the proposed interface here: http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt This has been implemented for x86 and powerpc, other architecture should mainly (I think) just need to add syscall numbers for the process_vm_readv and process_vm_writev. There are 32 bit compatibility versions for 64-bit kernels. For arch maintainers there are some simple tests to be able to quickly verify that the syscalls are working correctly here: http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgz Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: <linux-man@vger.kernel.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-20encrypted-keys: check hex2bin resultMimi Zohar1-3/+11
For each hex2bin call in encrypted keys, check that the ascii hex string is valid. On failure, return -EINVAL. Changelog v1: - hex2bin now returns an int Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2011-09-20trusted-keys: check hex2bin resultMimi Zohar1-4/+15
For each hex2bin call in trusted keys, check that the ascii hex string is valid. On failure, return -EINVAL. Changelog v1: - hex2bin now returns an int Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2011-09-15encrypted-keys: IS_ERR need include/err.hStephen Rothwell1-0/+1
Fixes this build error: security/keys/encrypted-keys/masterkey_trusted.c: In function 'request_trusted_key': security/keys/encrypted-keys/masterkey_trusted.c:35:2: error: implicit declaration of function 'IS_ERR' Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14encrypted-keys: remove trusted-keys dependencyMimi Zohar4-27/+64
Encrypted keys are decrypted/encrypted using either a trusted-key or, for those systems without a TPM, a user-defined key. This patch removes the trusted-keys and TCG_TPM dependencies. Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14encrypted-keys: create encrypted-keys directoryMimi Zohar6-1/+6
Move all files associated with encrypted keys to keys/encrypted-keys. Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-08-23KEYS: Correctly destroy key payloads when their keytype is removedDavid Howells3-208/+258
unregister_key_type() has code to mark a key as dead and make it unavailable in one loop and then destroy all those unavailable key payloads in the next loop. However, the loop to mark keys dead renders the key undetectable to the second loop by changing the key type pointer also. Fix this by the following means: (1) The key code has two garbage collectors: one deletes unreferenced keys and the other alters keyrings to delete links to old dead, revoked and expired keys. They can end up holding each other up as both want to scan the key serial tree under spinlock. Combine these into a single routine. (2) Move the dead key marking, dead link removal and dead key removal into the garbage collector as a three phase process running over the three cycles of the normal garbage collection procedure. This is tracked by the KEY_GC_REAPING_DEAD_1, _2 and _3 state flags. unregister_key_type() then just unlinks the key type from the list, wakes up the garbage collector and waits for the third phase to complete. (3) Downgrade the key types sem in unregister_key_type() once it has deleted the key type from the list so that it doesn't block the keyctl() syscall. (4) Dead keys that cannot be simply removed in the third phase have their payloads destroyed with the key's semaphore write-locked to prevent interference by the keyctl() syscall. There should be no in-kernel users of dead keys of that type by the point of unregistration, though keyctl() may be holding a reference. (5) Only perform timer recalculation in the GC if the timer actually expired. If it didn't, we'll get another cycle when it goes off - and if the key that actually triggered it has been removed, it's not a problem. (6) Only garbage collect link if the timer expired or if we're doing dead key clean up phase 2. (7) As only key_garbage_collector() is permitted to use rb_erase() on the key serial tree, it doesn't need to revalidate its cursor after dropping the spinlock as the node the cursor points to must still exist in the tree. (8) Drop the spinlock in the GC if there is contention on it or if we need to reschedule. After dealing with that, get the spinlock again and resume scanning. This has been tested in the following ways: (1) Run the keyutils testsuite against it. (2) Using the AF_RXRPC and RxKAD modules to test keytype removal: Load the rxrpc_s key type: # insmod /tmp/af-rxrpc.ko # insmod /tmp/rxkad.ko Create a key (http://people.redhat.com/~dhowells/rxrpc/listen.c): # /tmp/listen & [1] 8173 Find the key: # grep rxrpc_s /proc/keys 091086e1 I--Q-- 1 perm 39390000 0 0 rxrpc_s 52:2 Link it to a session keyring, preferably one with a higher serial number: # keyctl link 0x20e36251 @s Kill the process (the key should remain as it's linked to another place): # fg /tmp/listen ^C Remove the key type: rmmod rxkad rmmod af-rxrpc This can be made a more effective test by altering the following part of the patch: if (unlikely(gc_state & KEY_GC_REAPING_DEAD_2)) { /* Make sure everyone revalidates their keys if we marked a * bunch as being dead and make sure all keyring ex-payloads * are destroyed. */ kdebug("dead sync"); synchronize_rcu(); To call synchronize_rcu() in GC phase 1 instead. That causes that the keyring's old payload content to hang around longer until it's RCU destroyed - which usually happens after GC phase 3 is complete. This allows the destroy_dead_key branch to be tested. Reported-by: Benjamin Coddington <bcodding@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23KEYS: The dead key link reaper should be non-reentrantDavid Howells1-3/+3
The dead key link reaper should be non-reentrant as it relies on global state to keep track of where it's got to when it returns to the work queue manager to give it some air. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23KEYS: Make the key reaper non-reentrantDavid Howells1-1/+1
Make the key reaper non-reentrant by sticking it on the appropriate system work queue when we queue it. This will allow it to have global state and drop locks. It should probably be non-reentrant already as it may spend a long time holding the key serial spinlock, and so multiple entrants can spend long periods of time just sitting there spinning, waiting to get the lock. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23KEYS: Move the unreferenced key reaper to the keys garbage collector fileDavid Howells3-76/+85
Move the unreferenced key reaper function to the keys garbage collector file as that's a more appropriate place with the dead key link reaper. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23KEYS: __key_link() should use the RCU deref wrapper for keyring payloadsDavid Howells1-2/+1
__key_link() should use the RCU deref wrapper rcu_dereference_locked_keyring() for accessing keyring payloads rather than calling rcu_dereference_protected() directly. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23KEYS: keyctl_get_keyring_ID() should create a session keyring if create flag setDavid Howells1-2/+12
The keyctl call: keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 1) should create a session keyring if the process doesn't have one of its own because the create flag argument is set - rather than subscribing to and returning the user-session keyring as: keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0) will do. This can be tested by commenting out pam_keyinit in the /etc/pam.d files and running the following program a couple of times in a row: #include <stdio.h> #include <stdlib.h> #include <keyutils.h> int main(int argc, char *argv[]) { key_serial_t uk, usk, sk, nsk; uk = keyctl_get_keyring_ID(KEY_SPEC_USER_KEYRING, 0); usk = keyctl_get_keyring_ID(KEY_SPEC_USER_SESSION_KEYRING, 0); sk = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0); nsk = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 1); printf("keys: %08x %08x %08x %08x\n", uk, usk, sk, nsk); return 0; } Without this patch, I see: keys: 3975ddc7 119c0c66 119c0c66 119c0c66 keys: 3975ddc7 119c0c66 119c0c66 119c0c66 With this patch, I see: keys: 2cb4997b 34112878 34112878 17db2ce3 keys: 2cb4997b 34112878 34112878 39f3c73e As can be seen, the session keyring starts off the same as the user-session keyring each time, but with the patch a new session keyring is created when the create flag is set. Reported-by: Greg Wettstein <greg@enjellic.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Greg Wettstein <greg@enjellic.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23KEYS: If install_session_keyring() is given a keyring, it should install itDavid Howells1-1/+1
If install_session_keyring() is given a keyring, it should install it rather than just creating a new one anyway. This was accidentally broken in: commit d84f4f992cbd76e8f39c488cf0c5d123843923b1 Author: David Howells <dhowells@redhat.com> Date: Fri Nov 14 10:39:23 2008 +1100 Subject: CRED: Inaugurate COW credentials The impact of that commit is that pam_keyinit no longer works correctly if 'force' isn't specified against a login process. This is because: keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0) now always creates a new session keyring and thus the check whether the session keyring and the user-session keyring are the same is always false. This leads pam_keyinit to conclude that a session keyring is installed and it shouldn't be revoked by pam_keyinit here if 'revoke' is specified. Any system that specifies 'force' against pam_keyinit in the PAM configuration files for login methods (login, ssh, su -l, kdm, etc.) is not affected since that bypasses the broken check and forces the creation of a new session keyring anyway (for which the revoke flag is not cleared) - and any subsequent call to pam_keyinit really does have a session keyring already installed, and so the check works correctly there. Reverting to the previous behaviour will cause the kernel to subscribe the process to the user-session keyring as its session keyring if it doesn't have a session keyring of its own. pam_keyinit will detect this and install a new session keyring anyway (and won't clear the revert flag). This can be tested by commenting out pam_keyinit in the /etc/pam.d files and running the following program a couple of times in a row: #include <stdio.h> #include <stdlib.h> #include <keyutils.h> int main(int argc, char *argv[]) { key_serial_t uk, usk, sk; uk = keyctl_get_keyring_ID(KEY_SPEC_USER_KEYRING, 0); usk = keyctl_get_keyring_ID(KEY_SPEC_USER_SESSION_KEYRING, 0); sk = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0); printf("keys: %08x %08x %08x\n", uk, usk, sk); return 0; } Without the patch, I see: keys: 3884e281 24c4dfcf 22825f8e keys: 3884e281 24c4dfcf 068772be With the patch, I see: keys: 26be9c83 0e755ce0 0e755ce0 keys: 26be9c83 0e755ce0 0e755ce0 As can be seen, with the patch, the session keyring is the same as the user-session keyring each time; without the patch a new session keyring is generated each time. Reported-by: Greg Wettstein <greg@enjellic.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Greg Wettstein <greg@enjellic.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-07-27Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6Linus Torvalds5-53/+313
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (54 commits) tpm_nsc: Fix bug when loading multiple TPM drivers tpm: Move tpm_tis_reenable_interrupts out of CONFIG_PNP block tpm: Fix compilation warning when CONFIG_PNP is not defined TOMOYO: Update kernel-doc. tpm: Fix a typo tpm_tis: Probing function for Intel iTPM bug tpm_tis: Fix the probing for interrupts tpm_tis: Delay ACPI S3 suspend while the TPM is busy tpm_tis: Re-enable interrupts upon (S3) resume tpm: Fix display of data in pubek sysfs entry tpm_tis: Add timeouts sysfs entry tpm: Adjust interface timeouts if they are too small tpm: Use interface timeouts returned from the TPM tpm_tis: Introduce durations sysfs entry tpm: Adjust the durations if they are too small tpm: Use durations returned from TPM TOMOYO: Enable conditional ACL. TOMOYO: Allow using argv[]/envp[] of execve() as conditions. TOMOYO: Allow using executable's realpath and symlink's target as conditions. TOMOYO: Allow using owner/group etc. of file objects as conditions. ... Fix up trivial conflict in security/tomoyo/realpath.c
2011-07-11Merge branch 'master' into for-nextJiri Kosina1-3/+3
Sync with Linus' tree to be able to apply pending patches that are based on newer code already present upstream.
2011-07-08rcu: treewide: Do not use rcu_read_lock_held when calling rcu_dereference_checkMichal Hocko1-1/+0
Since ca5ecddf (rcu: define __rcu address space modifier for sparse) rcu_dereference_check use rcu_read_lock_held as a part of condition automatically so callers do not have to do that as well. Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-06-30Merge branch 'linus' into nextJames Morris1-3/+3
2011-06-27encrypted-keys: add ecryptfs format supportRoberto Sassu4-8/+180
The 'encrypted' key type defines its own payload format which contains a symmetric key randomly generated that cannot be used directly to mount an eCryptfs filesystem, because it expects an authentication token structure. This patch introduces the new format 'ecryptfs' that allows to store an authentication token structure inside the encrypted key payload containing a randomly generated symmetric key, as the same for the format 'default'. More details about the usage of encrypted keys with the eCryptfs filesystem can be found in the file 'Documentation/keys-ecryptfs.txt'. Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Acked-by: Gianluca Ramunno <ramunno@polito.it> Acked-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2011-06-27encrypted-keys: add key format supportRoberto Sassu1-40/+101
This patch introduces a new parameter, called 'format', that defines the format of data stored by encrypted keys. The 'default' format identifies encrypted keys containing only the symmetric key, while other formats can be defined to support additional information. The 'format' parameter is written in the datablob produced by commands 'keyctl print' or 'keyctl pipe' and is integrity protected by the HMAC. Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Acked-by: Gianluca Ramunno <ramunno@polito.it> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>