linux-toradex.git/security/keys, branch v2.6.14-rc4

[PATCH] Keys: Possessor permissions should be additive

2005-10-08T21:54:48+00:00

This patch makes the possessor permissions on a key additive with
user/group/other permissions on the same key.

This permits extra rights to be granted to the possessor of a key without
taking away any rights conferred by them owning the key or having common group
membership.

Signed-Off-By: David Howells 
Signed-off-by: Linus Torvalds

[PATCH] Keys: Split key permissions checking into a .c file

2005-10-08T21:53:31+00:00

The attached patch splits key permissions checking out of key-ui.h and
moves it into a .c file.  It's quite large and called quite a lot, and
it's about to get bigger with the addition of LSM support for keys...

key_any_permission() is also discarded as it's no longer used.

Signed-Off-By: David Howells 
Signed-off-by: Linus Torvalds

[PATCH] Keys: Add request-key process documentation

2005-10-08T21:53:31+00:00

The attached patch adds documentation for the process by which request-key
works, including how it permits helper processes to gain access to the
requestor's keyrings.

Signed-Off-By: David Howells 
Signed-off-by: Linus Torvalds

[PATCH] key: plug request_key_auth memleak

2005-10-08T21:53:31+00:00

Plug request_key_auth memleak.  This can be triggered by unprivileged
users, so is local DoS.

Signed-off-by: Chris Wright 
Signed-Off-By: David Howells 
Signed-off-by: Linus Torvalds

[PATCH] Keys: Add possessor permissions to keys [try #3]

2005-09-28T16:10:47+00:00

The attached patch adds extra permission grants to keys for the possessor of a
key in addition to the owner, group and other permissions bits. This makes
SUID binaries easier to support without going as far as labelling keys and key
targets using the LSM facilities.

This patch adds a second "pointer type" to key structures (struct key_ref *)
that can have the bottom bit of the address set to indicate the possession of
a key. This is propagated through searches from the keyring to the discovered
key. It has been made a separate type so that the compiler can spot attempts
to dereference a potentially incorrect pointer.

The "possession" attribute can't be attached to a key structure directly as
it's not an intrinsic property of a key.

Pointers to keys have been replaced with struct key_ref *'s wherever
possession information needs to be passed through.

This does assume that the bottom bit of the pointer will always be zero on
return from kmem_cache_alloc().

The key reference type has been made into a typedef so that at least it can be
located in the sources, even though it's basically a pointer to an undefined
type. I've also renamed the accessor functions to be more useful, and all
reference variables should now end in "_ref".

Signed-Off-By: David Howells 
Signed-off-by: Linus Torvalds

[PATCH] Destruction of failed keyring oopses

2005-08-04T20:11:14+00:00

The attached patch makes sure that a keyring that failed to instantiate
properly is destroyed without oopsing [CAN-2005-2099].

The problem occurs in three stages:

 (1) The key allocator initialises the type-specific data to all zeroes. In
     the case of a keyring, this will become a link in the keyring name list
     when the keyring is instantiated.

 (2) If a user (any user) attempts to add a keyring with anything other than
     an empty payload, the keyring instantiation function will fail with an
     error and won't add the keyring to the name list.

 (3) The keyring's destructor then sees that the keyring has a description
     (name) and tries to remove the keyring from the name list, which oopses
     because the link pointers are both zero.

This bug permits any user to take down a box trivially.

Signed-Off-By: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Error during attempt to join key management session can leave semaphore pinned

2005-08-04T20:11:14+00:00

The attached patch prevents an error during the key session joining operation
from hanging future joins in the D state [CAN-2005-2098].

The problem is that the error handling path for the KEYCTL_JOIN_SESSION_KEYRING
operation has one error path that doesn't release the session management
semaphore. Further attempts to get the semaphore will then sleep for ever in
the D state.

This can happen in four situations, all involving an attempt to allocate a new
session keyring:

 (1) ENOMEM.

 (2) The users key quota being reached.

 (3) A keyring name that is an empty string.

 (4) A keyring name that is too long.

Any user may attempt this operation, and so any user can cause the problem to
occur.

Signed-Off-By: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Keys: Fix key management syscall interface bugs

2005-08-04T15:20:47+00:00

This fixes five bugs in the key management syscall interface:

 (1) add_key() returns 0 rather than EINVAL if the key type is "".

     Checking the key type isn't "" should be left to lookup_user_key().

 (2) request_key() returns ENOKEY rather than EPERM if the key type begins
     with a ".".

     lookup_user_key() can't do this because internal key types begin with a
     ".".

 (3) Key revocation always returns 0, even if it fails.

 (4) Key read can return EAGAIN rather than EACCES under some circumstances.

     A key is permitted to by read by a process if it doesn't grant read
     access, but it does grant search access and it is in the process's
     keyrings. That search returns EAGAIN if it fails, and this needs
     translating to EACCES.

 (5) request_key() never adds the new key to the destination keyring if one is
     supplied.

     The wrong macro was being used to test for an error condition: PTR_ERR()
     will always return true, whether or not there's an error; this should've
     been IS_ERR().

Signed-Off-By: David Howells 
Signed-Off-By: Linus Torvalds

[PATCH] Keys: Base keyring size on key pointer not key struct

2005-07-08T01:23:46+00:00

The attached patch makes the keyring functions calculate the new size of a
keyring's payload based on the size of pointer to the key struct, not the size
of the key struct itself.

Signed-Off-By: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] RCU: clean up a few remaining synchronize_kernel() calls

2005-06-25T23:24:38+00:00

2.6.12-rc6-mm1 has a few remaining synchronize_kernel()s, some (but not
all) in comments.  This patch changes these synchronize_kernel() calls (and
comments) to synchronize_rcu() or synchronize_sched() as follows:

- arch/x86_64/kernel/mce.c mce_read(): change to synchronize_sched() to
  handle races with machine-check exceptions (synchronize_rcu() would not cut
  it given RCU implementations intended for hardcore realtime use.

- drivers/input/serio/i8042.c i8042_stop(): change to synchronize_sched() to
  handle races with i8042_interrupt() interrupt handler.  Again,
  synchronize_rcu() would not cut it given RCU implementations intended for
  hardcore realtime use.

- include/*/kdebug.h comments: change to synchronize_sched() to handle races
  with NMIs.  As before, synchronize_rcu() would not cut it...

- include/linux/list.h comment: change to synchronize_rcu(), since this
  comment is for list_del_rcu().

- security/keys/key.c unregister_key_type(): change to synchronize_rcu(),
  since this is interacting with RCU read side.

- security/keys/process_keys.c install_session_keyring(): change to
  synchronize_rcu(), since this is interacting with RCU read side.

Signed-off-by: "Paul E. McKenney" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds