linux/security, branch v2.6.36-rc5

KEYS: Fix bug in keyctl_session_to_parent() if parent has no session keyring

2010-09-10T14:30:00Z

Fix a bug in keyctl_session_to_parent() whereby it tries to check the ownership of the parent process's session keyring whether or not the parent has a session keyring [CVE-2010-2960]. This results in the following oops: BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0 IP: [] keyctl_session_to_parent+0x251/0x443 ... Call Trace: [] ? keyctl_session_to_parent+0x67/0x443 [] ? __do_fault+0x24b/0x3d0 [] sys_keyctl+0xb4/0xb8 [] system_call_fastpath+0x16/0x1b if the parent process has no session keyring. If the system is using pam_keyinit then it mostly protected against this as all processes derived from a login will have inherited the session keyring created by pam_keyinit during the log in procedure. To test this, pam_keyinit calls need to be commented out in /etc/pam.d/. Reported-by: Tavis Ormandy Signed-off-by: David Howells Acked-by: Tavis Ormandy Signed-off-by: Linus Torvalds

KEYS: Fix RCU no-lock warning in keyctl_session_to_parent()

2010-09-10T14:30:00Z

There's an protected access to the parent process's credentials in the middle of keyctl_session_to_parent(). This results in the following RCU warning: =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- security/keys/keyctl.c:1291 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by keyctl-session-/2137: #0: (tasklist_lock){.+.+..}, at: [] keyctl_session_to_parent+0x60/0x236 stack backtrace: Pid: 2137, comm: keyctl-session- Not tainted 2.6.36-rc2-cachefs+ #1 Call Trace: [] lockdep_rcu_dereference+0xaa/0xb3 [] keyctl_session_to_parent+0xed/0x236 [] sys_keyctl+0xb4/0xb6 [] system_call_fastpath+0x16/0x1b The code should take the RCU read lock to make sure the parents credentials don't go away, even though it's holding a spinlock and has IRQ disabled. Signed-off-by: David Howells Signed-off-by: Linus Torvalds

ima: always maintain counters

2010-09-07T23:51:41Z

commit 8262bb85da allocated the inode integrity struct (iint) before any inodes were created. Only after IMA was initialized in late_initcall were the counters updated. This patch updates the counters, whether or not IMA has been initialized, to resolve 'imbalance' messages. This patch fixes the bug as reported in bugzilla: 15673. When the i915 is builtin, the ring_buffer is initialized before IMA, causing the imbalance message on suspend. Reported-by: Thomas Meyer Signed-off-by: Mimi Zohar Tested-by: Thomas Meyer Tested-by: David Safford Cc: Stable Kernel Signed-off-by: James Morris

AppArmor: Fix locking from removal of profile namespace

2010-09-07T23:19:34Z

The locking for profile namespace removal is wrong, when removing a profile namespace, it needs to be removed from its parent's list. Lock the parent of namespace list instead of the namespace being removed. Signed-off-by: John Johansen Signed-off-by: James Morris

AppArmor: Fix splitting an fqname into separate namespace and profile names

2010-09-07T23:19:31Z

As per Dan Carpenter If we have a ns name without a following profile then in the original code it did "*ns_name = &name[1];". "name" is NULL so "*ns_name" is 0x1. That isn't useful and could cause an oops when this function is called from aa_remove_profiles(). Beyond this the assignment of the namespace name was wrong in the case where the profile name was provided as it was being set to &name[1] after name = skip_spaces(split + 1); Move the ns_name assignment before updating name for the split and also add skip_spaces, making the interface more robust. Signed-off-by: John Johansen Signed-off-by: James Morris

AppArmor: Fix security_task_setrlimit logic for 2.6.36 changes

2010-09-07T23:19:29Z

2.6.36 introduced the abilitiy to specify the task that is having its rlimits set. Update mediation to ensure that confined tasks can only set their own group_leader as expected by current policy. Add TODO note about extending policy to support setting other tasks rlimits. Signed-off-by: John Johansen Signed-off-by: James Morris

AppArmor: Drop hack to remove appended " (deleted)" string

2010-09-07T23:19:24Z

The 2.6.36 kernel has refactored __d_path() so that it no longer appends " (deleted)" to unlinked paths. So drop the hack that was used to detect and remove the appended string. Signed-off-by: John Johansen Signed-off-by: James Morris

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2010-08-18T16:35:08Z

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: fs: brlock vfsmount_lock fs: scale files_lock lglock: introduce special lglock and brlock spin locks tty: fix fu_list abuse fs: cleanup files_lock locking fs: remove extra lookup in __lookup_hash fs: fs_struct rwlock to spinlock apparmor: use task path helpers fs: dentry allocation consolidation fs: fix do_lookup false negative mbcache: Limit the maximum number of cache entries hostfs ->follow_link() braino hostfs: dumb (and usually harmless) tpyo - strncpy instead of strlcpy remove SWRITE* I/O types kill BH_Ordered flag vfs: update ctime when changing the file's permission by setfacl cramfs: only unlock new inodes fix reiserfs_evict_inode end_writeback second call

tty: fix fu_list abuse

2010-08-18T12:35:47Z

tty: fix fu_list abuse tty code abuses fu_list, which causes a bug in remount,ro handling. If a tty device node is opened on a filesystem, then the last link to the inode removed, the filesystem will be allowed to be remounted readonly. This is because fs_may_remount_ro does not find the 0 link tty inode on the file sb list (because the tty code incorrectly removed it to use for its own purpose). This can result in a filesystem with errors after it is marked "clean". Taking idea from Christoph's initial patch, allocate a tty private struct at file->private_data and put our required list fields in there, linking file and tty. This makes tty nodes behave the same way as other device nodes and avoid meddling with the vfs, and avoids this bug. The error handling is not trivial in the tty code, so for this bugfix, I take the simple approach of using __GFP_NOFAIL and don't worry about memory errors. This is not a problem because our allocator doesn't fail small allocs as a rule anyway. So proper error handling is left as an exercise for tty hackers. [ Arguably filesystem's device inode would ideally be divorced from the driver's pseudo inode when it is opened, but in practice it's not clear whether that will ever be worth implementing. ] Cc: linux-kernel@vger.kernel.org Cc: Christoph Hellwig Cc: Alan Cox Cc: Greg Kroah-Hartman Signed-off-by: Nick Piggin Signed-off-by: Al Viro

fs: cleanup files_lock locking

2010-08-18T12:35:47Z

fs: cleanup files_lock locking Lock tty_files with a new spinlock, tty_files_lock; provide helpers to manipulate the per-sb files list; unexport the files_lock spinlock. Cc: linux-kernel@vger.kernel.org Cc: Christoph Hellwig Cc: Alan Cox Acked-by: Andi Kleen Acked-by: Greg Kroah-Hartman Signed-off-by: Nick Piggin Signed-off-by: Al Viro