linux/security/keys, branch v3.0.62

KEYS: Fix a NULL pointer deref in the user-defined key type

2011-11-21T22:31:18Z

commit 9f35a33b8d06263a165efe3541d9aa0cdbd70b3b upstream. 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: [] __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:[] [] __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: [] call_rcu_sched+0x10/0x12 [] user_update+0x8d/0xa2 [] key_create_or_update+0x236/0x270 [] sys_add_key+0x123/0x17e [] system_call_fastpath+0x16/0x1b Signed-off-by: David Howells Acked-by: Jeff Layton Acked-by: Neil Horman Acked-by: Steve Dickson Acked-by: James Morris Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

KEYS: Fix error handling in construct_key_and_link()

2011-06-22T01:31:45Z

Fix error handling in construct_key_and_link(). If construct_alloc_key() returns an error, it shouldn't pass out through the normal path as the key_serial() called by the kleave() statement will oops when it gets an error code in the pointer: BUG: unable to handle kernel paging request at ffffffffffffff84 IP: [] request_key_and_link+0x4d7/0x52f .. Call Trace: [] request_key+0x41/0x75 [] cifs_get_spnego_key+0x206/0x226 [cifs] [] CIFS_SessSetup+0x511/0x1234 [cifs] [] cifs_setup_session+0x90/0x1ae [cifs] [] cifs_get_smb_ses+0x34b/0x40f [cifs] [] cifs_mount+0x13f/0x504 [cifs] [] cifs_do_mount+0xc4/0x672 [cifs] [] mount_fs+0x69/0x155 [] vfs_kern_mount+0x63/0xa0 [] do_kern_mount+0x4d/0xdf [] do_mount+0x63c/0x69f [] sys_mount+0x88/0xc2 [] system_call_fastpath+0x16/0x1b Signed-off-by: David Howells Acked-by: Jeff Layton Signed-off-by: Linus Torvalds

KEYS/DNS: Fix ____call_usermodehelper() to not lose the session keyring

2011-06-17T16:40:48Z

____call_usermodehelper() now erases any credentials set by the subprocess_inf::init() function. The problem is that commit 17f60a7da150 ("capabilites: allow the application of capability limits to usermode helpers") creates and commits new credentials with prepare_kernel_cred() after the call to the init() function. This wipes all keyrings after umh_keys_init() is called. The best way to deal with this is to put the init() call just prior to the commit_creds() call, and pass the cred pointer to init(). That means that umh_keys_init() and suchlike can modify the credentials _before_ they are published and potentially in use by the rest of the system. This prevents request_key() from working as it is prevented from passing the session keyring it set up with the authorisation token to /sbin/request-key, and so the latter can't assume the authority to instantiate the key. This causes the in-kernel DNS resolver to fail with ENOKEY unconditionally. Signed-off-by: David Howells Acked-by: Eric Paris Tested-by: Jeff Layton Signed-off-by: Linus Torvalds

Merge branch 'docs-move' of git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs

2011-05-27T17:25:02Z

* 'docs-move' of git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs: Create Documentation/security/, move LSM-, credentials-, and keys-related files from Documentation/ to Documentation/security/, add Documentation/security/00-INDEX, and update all occurrences of Documentation/ to Documentation/security/.

Set cred->user_ns in key_replace_session_keyring

2011-05-26T20:49:19Z

Since this cred was not created with copy_creds(), it needs to get initialized. Otherwise use of syscall(__NR_keyctl, KEYCTL_SESSION_TO_PARENT); can lead to a NULL deref. Thanks to Robert for finding this. But introduced by commit 47a150edc2a ("Cache user_ns in struct cred"). Signed-off-by: Serge E. Hallyn Reported-by: Robert Święcki Cc: David Howells Cc: stable@kernel.org (2.6.39) Signed-off-by: Linus Torvalds

Merge branch 'next' into for-linus

2011-05-24T12:55:24Z

Create Documentation/security/,

2011-05-19T22:59:38Z

move LSM-, credentials-, and keys-related files from Documentation/ to Documentation/security/, add Documentation/security/00-INDEX, and update all occurrences of Documentation/ to Documentation/security/.

security,rcu: convert call_rcu(user_update_rcu_disposal) to kfree_rcu()

2011-05-08T05:50:54Z

The rcu callback user_update_rcu_disposal() just calls a kfree(), so we use kfree_rcu() instead of the call_rcu(user_update_rcu_disposal). Signed-off-by: Lai Jiangshan Signed-off-by: Paul E. McKenney Acked-by: David Howells Reviewed-by: Josh Triplett

KEYS: Make request_key() and co. return an error for a negative key

2011-03-17T00:59:49Z

Make request_key() and co. return an error for a negative or rejected key. If the key was simply negated, then return ENOKEY, otherwise return the error with which it was rejected. Without this patch, the following command returns a key number (with the latest keyutils): [root@andromeda ~]# keyctl request2 user debug:foo rejected @s 586569904 Trying to print the key merely gets you a permission denied error: [root@andromeda ~]# keyctl print 586569904 keyctl_read_alloc: Permission denied Doing another request_key() call does get you the error, as long as it hasn't expired yet: [root@andromeda ~]# keyctl request user debug:foo request_key: Key was rejected by service Signed-off-by: David Howells Signed-off-by: James Morris

KEYS: Improve /proc/keys

2011-03-17T00:59:32Z

Improve /proc/keys by: (1) Don't attempt to summarise the payload of a negated key. It won't have one. To this end, a helper function - key_is_instantiated() has been added that allows the caller to find out whether the key is positively instantiated (as opposed to being uninstantiated or negatively instantiated). (2) Do show keys that are negative, expired or revoked rather than hiding them. This requires an override flag (no_state_check) to be passed to search_my_process_keyrings() and keyring_search_aux() to suppress this check. Without this, keys that are possessed by the caller, but only grant permissions to the caller if possessed are skipped as the possession check fails. Keys that are visible due to user, group or other checks are visible with or without this patch. Signed-off-by: David Howells Signed-off-by: James Morris