linux-uconsole/security
David Howells 31a05f7dd7 KEYS: Fix a NULL pointer deref in the user-defined key type
commit 9f35a33b8d 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: [<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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-21 14:31:18 -08:00
..
apparmor AppArmor: Fix masking of capabilities in complain mode 2011-08-04 21:58:42 -07:00
integrity/ima ima: remove unnecessary call to ima_must_measure 2011-02-23 16:38:52 -05:00
keys KEYS: Fix a NULL pointer deref in the user-defined key type 2011-11-21 14:31:18 -08:00
selinux Merge branch 'for-linus' of git://git.infradead.org/users/eparis/selinux into for-linus 2011-06-15 09:41:48 +10:00
smack Merge commit 'v2.6.39' into 20110526 2011-05-26 17:20:14 -04:00
tomoyo TOMOYO: Fix oops in tomoyo_mount_acl(). 2011-06-14 15:18:42 +10:00
capability.c SECURITY: Move exec_permission RCU checks into security modules 2011-04-25 10:20:32 -04:00
commoncap.c capabilities: do not special case exec of init 2011-04-04 10:31:06 +10:00
device_cgroup.c devcgroup_inode_permission: take "is it a device node" checks to inlined wrapper 2011-06-20 10:46:04 -04:00
inode.c convert get_sb_single() users 2010-10-29 04:16:28 -04:00
Kconfig security: select correct default LSM_MMAP_MIN_ADDR on ARM. 2011-03-22 09:35:12 +11:00
lsm_audit.c LSM: separate LSM_AUDIT_DATA_DENTRY from LSM_AUDIT_DATA_PATH 2011-04-25 18:14:07 -04:00
Makefile AppArmor: Enable configuring and building of the AppArmor security module 2010-08-02 15:38:34 +10:00
min_addr.c mmap_min_addr check CAP_SYS_RAWIO only for write 2010-04-23 08:56:31 +10:00
security.c SECURITY: Move exec_permission RCU checks into security modules 2011-04-25 10:20:32 -04:00