kernel/linux.git/security, branch linux-2.6.35.y

CRED: Fix BUG() upon security_cred_alloc_blank() failure

2011-03-31T18:58:05+00:00

commit 2edeaa34a6e3f2c43b667f6c4f7b27944b811695 upstream. In cred_alloc_blank() since 2.6.32, abort_creds(new) is called with new->security == NULL and new->magic == 0 when security_cred_alloc_blank() returns an error. As a result, BUG() will be triggered if SELinux is enabled or CONFIG_DEBUG_CREDENTIALS=y. If CONFIG_DEBUG_CREDENTIALS=y, BUG() is called from __invalid_creds() because cred->magic == 0. Failing that, BUG() is called from selinux_cred_free() because selinux_cred_free() is not expecting cred->security == NULL. This does not affect smack_cred_free(), tomoyo_cred_free() or apparmor_cred_free(). Fix these bugs by (1) Set new->magic before calling security_cred_alloc_blank(). (2) Handle null cred->security in creds_are_invalid() and selinux_cred_free(). Signed-off-by: Tetsuo Handa Signed-off-by: David Howells Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman Signed-off-by: Andi Kleen

SELinux: do not compute transition labels on mountpoint labeled filesystems

2011-03-31T18:57:54+00:00

commit 415103f9932d45f7927f4b17e3a9a13834cdb9a1 upstream. selinux_inode_init_security computes transitions sids even for filesystems that use mount point labeling. It shouldn't do that. It should just use the mount point label always and no matter what. This causes 2 problems. 1) it makes file creation slower than it needs to be since we calculate the transition sid and 2) it allows files to be created with a different label than the mount point! # id -Z staff_u:sysadm_r:sysadm_t:s0-s0:c0.c1023 # sesearch --type --class file --source sysadm_t --target tmp_t Found 1 semantic te rules: type_transition sysadm_t tmp_t : file user_tmp_t; # mount -o loop,context="system_u:object_r:tmp_t:s0" /tmp/fs /mnt/tmp # ls -lZ /mnt/tmp drwx------. root root system_u:object_r:tmp_t:s0 lost+found # touch /mnt/tmp/file1 # ls -lZ /mnt/tmp -rw-r--r--. root root staff_u:object_r:user_tmp_t:s0 file1 drwx------. root root system_u:object_r:tmp_t:s0 lost+found Whoops, we have a mount point labeled filesystem tmp_t with a user_tmp_t labeled file! Signed-off-by: Eric Paris Signed-off-by: Andi Kleen Reviewed-by: Reviewed-by: James Morris Signed-off-by: Greg Kroah-Hartman

SELinux: define permissions for DCB netlink messages

2011-03-31T18:57:54+00:00

commit 350e4f31e0eaf56dfc3b328d24a11bdf42a41fb8 upstream. Commit 2f90b865 added two new netlink message types to the netlink route socket. SELinux has hooks to define if netlink messages are allowed to be sent or received, but it did not know about these two new message types. By default we allow such actions so noone likely noticed. This patch adds the proper definitions and thus proper permissions enforcement. Signed-off-by: Eric Paris Signed-off-by: Andi Kleen Cc: James Morris Signed-off-by: Greg Kroah-Hartman

ima: fix add LSM rule bug

2011-02-06T19:03:51+00:00

commit 867c20265459d30a01b021a9c1e81fb4c5832aa9 upstream. If security_filter_rule_init() doesn't return a rule, then not everything is as fine as the return code implies. This bug only occurs when the LSM (eg. SELinux) is disabled at runtime. Adding an empty LSM rule causes ima_match_rules() to always succeed, ignoring any remaining rules. default IMA TCB policy: # PROC_SUPER_MAGIC dont_measure fsmagic=0x9fa0 # SYSFS_MAGIC dont_measure fsmagic=0x62656572 # DEBUGFS_MAGIC dont_measure fsmagic=0x64626720 # TMPFS_MAGIC dont_measure fsmagic=0x01021994 # SECURITYFS_MAGIC dont_measure fsmagic=0x73636673 < LSM specific rule > dont_measure obj_type=var_log_t measure func=BPRM_CHECK measure func=FILE_MMAP mask=MAY_EXEC measure func=FILE_CHECK mask=MAY_READ uid=0 Thus without the patch, with the boot parameters 'tcb selinux=0', adding the above 'dont_measure obj_type=var_log_t' rule to the default IMA TCB measurement policy, would result in nothing being measured. The patch prevents the default TCB policy from being replaced. Signed-off-by: Mimi Zohar Signed-off-by: Andi Kleen Cc: James Morris Acked-by: Serge Hallyn Cc: David Safford Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

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

2010-09-27T00:18:36+00:00

commit 3d96406c7da1ed5811ea52a3b0905f4f0e295376 upstream. 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 Cc: dann frazier Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

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

2010-09-27T00:18:35+00:00

commit 9d1ac65a9698513d00e5608d93fca0c53f536c14 upstream. 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 Cc: dann frazier Signed-off-by: Greg Kroah-Hartman

ima: always maintain counters

2010-09-20T20:36:22+00:00

commit e950598d43dce8d97e7d5270808393425d1e5cbd upstream. 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 Signed-off-by: James Morris Signed-off-by: Greg Kroah-Hartman

KEYS: Propagate error code instead of returning -EINVAL

2010-06-27T14:02:34+00:00

This is from a Smatch check I'm writing. strncpy_from_user() returns -EFAULT on error so the first change just silences a warning but doesn't change how the code works. The other change is a bug fix because install_thread_keyring_to_cred() can return a variety of errors such as -EINVAL, -EEXIST, -ENOMEM or -EKEYREVOKED. Signed-off-by: Dan Carpenter Signed-off-by: David Howells Signed-off-by: Linus Torvalds

keyctl_session_to_parent(): use thread_group_empty() to check singlethreadness

2010-05-27T16:12:47+00:00

No functional changes. keyctl_session_to_parent() is the only user of signal->count which needs the correct value. Change it to use thread_group_empty() instead, this must be strictly equivalent under tasklist, and imho looks better. Signed-off-by: Oleg Nesterov Acked-by: David Howells Cc: Peter Zijlstra Acked-by: Roland McGrath Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

umh: creds: convert call_usermodehelper_keys() to use subprocess_info->init()

2010-05-27T16:12:45+00:00

call_usermodehelper_keys() uses call_usermodehelper_setkeys() to change subprocess_info->cred in advance. Now that we have info->init() we can change this code to set tgcred->session_keyring in context of execing kernel thread. Note: since currently call_usermodehelper_keys() is never called with UMH_NO_WAIT, call_usermodehelper_keys()->key_get() and umh_keys_cleanup() are not really needed, we could rely on install_session_keyring_to_cred() which does key_get() on success. Signed-off-by: Oleg Nesterov Acked-by: Neil Horman Acked-by: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds