SELinux: Fix kernel BUG on empty security contexts.

Setting an empty security context (length=0) on a file will
lead to incorrectly dereferencing the type and other fields
of the security context structure, yielding a kernel BUG.
As a zero-length security context is never valid, just reject
all such security contexts whether coming from userspace
via setxattr or coming from the filesystem upon a getxattr
request by SELinux.

Setting a security context value (empty or otherwise) unknown to
SELinux in the first place is only possible for a root process
(CAP_MAC_ADMIN), and, if running SELinux in enforcing mode, only
if the corresponding SELinux mac_admin permission is also granted
to the domain by policy.  In Fedora policies, this is only allowed for
specific domains such as livecd for setting down security contexts
that are not defined in the build host policy.

[On Android, this can only be set by root/CAP_MAC_ADMIN processes,
and if running SELinux in enforcing mode, only if mac_admin permission
is granted in policy.  In Android 4.4, this would only be allowed for
root/CAP_MAC_ADMIN processes that are also in unconfined domains. In current
AOSP master, mac_admin is not allowed for any domains except the recovery
console which has a legitimate need for it.  The other potential vector
is mounting a maliciously crafted filesystem for which SELinux fetches
xattrs (e.g. an ext4 filesystem on a SDcard).  However, the end result is
only a local denial-of-service (DOS) due to kernel BUG.  This fix is
queued for 3.14.]

Reproducer:
su
setenforce 0
touch foo
setfattr -n security.selinux foo

Caveat:
Relabeling or removing foo after doing the above may not be possible
without booting with SELinux disabled.  Any subsequent access to foo
after doing the above will also trigger the BUG.

BUG output from Matthew Thode:
[  473.893141] ------------[ cut here ]------------
[  473.962110] kernel BUG at security/selinux/ss/services.c:654!
[  473.995314] invalid opcode: 0000 [#6] SMP
[  474.027196] Modules linked in:
[  474.058118] CPU: 0 PID: 8138 Comm: ls Tainted: G      D   I
3.13.0-grsec #1
[  474.116637] Hardware name: Supermicro X8ST3/X8ST3, BIOS 2.0
07/29/10
[  474.149768] task: ffff8805f50cd010 ti: ffff8805f50cd488 task.ti:
ffff8805f50cd488
[  474.183707] RIP: 0010:[<ffffffff814681c7>]  [<ffffffff814681c7>]
context_struct_compute_av+0xce/0x308
[  474.219954] RSP: 0018:ffff8805c0ac3c38  EFLAGS: 00010246
[  474.252253] RAX: 0000000000000000 RBX: ffff8805c0ac3d94 RCX:
0000000000000100
[  474.287018] RDX: ffff8805e8aac000 RSI: 00000000ffffffff RDI:
ffff8805e8aaa000
[  474.321199] RBP: ffff8805c0ac3cb8 R08: 0000000000000010 R09:
0000000000000006
[  474.357446] R10: 0000000000000000 R11: ffff8805c567a000 R12:
0000000000000006
[  474.419191] R13: ffff8805c2b74e88 R14: 00000000000001da R15:
0000000000000000
[  474.453816] FS:  00007f2e75220800(0000) GS:ffff88061fc00000(0000)
knlGS:0000000000000000
[  474.489254] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  474.522215] CR2: 00007f2e74716090 CR3: 00000005c085e000 CR4:
00000000000207f0
[  474.556058] Stack:
[  474.584325]  ffff8805c0ac3c98 ffffffff811b549b ffff8805c0ac3c98
ffff8805f1190a40
[  474.618913]  ffff8805a6202f08 ffff8805c2b74e88 00068800d0464990
ffff8805e8aac860
[  474.653955]  ffff8805c0ac3cb8 000700068113833a ffff880606c75060
ffff8805c0ac3d94
[  474.690461] Call Trace:
[  474.723779]  [<ffffffff811b549b>] ? lookup_fast+0x1cd/0x22a
[  474.778049]  [<ffffffff81468824>] security_compute_av+0xf4/0x20b
[  474.811398]  [<ffffffff8196f419>] avc_compute_av+0x2a/0x179
[  474.843813]  [<ffffffff8145727b>] avc_has_perm+0x45/0xf4
[  474.875694]  [<ffffffff81457d0e>] inode_has_perm+0x2a/0x31
[  474.907370]  [<ffffffff81457e76>] selinux_inode_getattr+0x3c/0x3e
[  474.938726]  [<ffffffff81455cf6>] security_inode_getattr+0x1b/0x22
[  474.970036]  [<ffffffff811b057d>] vfs_getattr+0x19/0x2d
[  475.000618]  [<ffffffff811b05e5>] vfs_fstatat+0x54/0x91
[  475.030402]  [<ffffffff811b063b>] vfs_lstat+0x19/0x1b
[  475.061097]  [<ffffffff811b077e>] SyS_newlstat+0x15/0x30
[  475.094595]  [<ffffffff8113c5c1>] ? __audit_syscall_entry+0xa1/0xc3
[  475.148405]  [<ffffffff8197791e>] system_call_fastpath+0x16/0x1b
[  475.179201] Code: 00 48 85 c0 48 89 45 b8 75 02 0f 0b 48 8b 45 a0 48
8b 3d 45 d0 b6 00 8b 40 08 89 c6 ff ce e8 d1 b0 06 00 48 85 c0 49 89 c7
75 02 <0f> 0b 48 8b 45 b8 4c 8b 28 eb 1e 49 8d 7d 08 be 80 01 00 00 e8
[  475.255884] RIP  [<ffffffff814681c7>]
context_struct_compute_av+0xce/0x308
[  475.296120]  RSP <ffff8805c0ac3c38>
[  475.328734] ---[ end trace f076482e9d754adc ]---

[sds:  commit message edited to note Android implications and
to generate a unique Change-Id for gerrit]

Change-Id: I4d5389f0cfa72b5f59dada45081fa47e03805413
Reported-by:  Matthew Thode <mthode@mthode.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
fix false disconnect due to a signal sent to the reading process

- In the current implementation, when a signal is sent to the reading process,
  read is cancelled by calling usb_ep_dequeue, which lead into calling
  acc_complete_out with ECONNRESET, but the current logic treats it as
  disconnection, which makes the device inaccessible until cable is actually
  disconnected.
- The fix calls disconnect only when ESHUTDOWN error is passed.
- If data has already arrived while trying cancelling, the data is marked
  as available, and it will be read out on the next read. This is necessary
  as USB bulk is assumed to guarantee no data loss.

Change-Id: I87a360685e6760f9bff734c7056fe2488032e1fc
Signed-off-by: keunyoung <keunyoung@google.com>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
selinux: add a ugly workaround to bail early when selinux tries to free a socket that is still in use and it ends in a Kernel panic. These lines are from opensource.samsung.com. While this will most likely put a bandaid over this Kernel panic it does not fix the bug so it might occur somewhere else if the same conditions are met but since I have only seen panics from this hook then we may as well sleep in peace.

Change-Id: I5137878d98db001dd716bf642d48c4bae38dcd7f
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
ipv4: Dump stack on attempt to release alive inet socket

We hide the bug, that will make SELinux bomb out. Let's dump the stack
when it happens to have at least a chance to find the cause.

Change-Id: I9cbe03ef3e97b806fbb09cbab99e2ac6a89656f8
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
usb: gadget: Fix response available notify count usage

The outstanding responses are purged and notify count is reset
during bus suspend. But the notify interrupt endpoint is not flushed.
If a request is pending with the controller, It gets finished during
resume and the notify count is decremented in the completion handler.
As the notify count is reset during the suspend its become negative now.
As the counter is not zero, interrupt notifications are queued even
though there are no responses. This is leading to watchdog bark due to
an error print messages.

Flush the notify endpoint before resetting the notify counter during
suspend. As we are modifying notify counter under spin lock, atomic
variable is not required. Ensure that notify counter never
becomes negative.

CRs-Fixed: 607029
Change-Id: I78cb7a585c1c2b527ca6b46bc99e7db8067ee21a
Signed-off-by: ChandanaKishori Chiluveru <cchilu@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
regulator: core: if voltage scaling fails, restore original voltage values

Change-Id: I6f41096966aa5e5f9d834049ca9b2ae2d8156285
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Tested-by: Robert Nelson <robertcnelson@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Git-commit: 92d7a55879c01b30349045501108e775655a4b92
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[keliu@codeaurora.org: resolve merge conflicts]
Signed-off-by: Ke Liu <keliu@codeaurora.org>

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
msm: thermal: the wq can freezes during freezer phase.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
cpufreq: bail early if target_freq == current.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
msm: hotplug: Cleanup hotplugging routines
cpufreq: add new routine cpufreq_verify_within_cpu_limits()

Most of the users of cpufreq_verify_within_limits() calls it for
limiting with min/max from policy->cpuinfo. We can make that code
simple by introducing another routine which will do this for them
automatically.

This patch adds another routine cpufreq_verify_within_cpu_limits()
and updates others to use it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
msm: hotplug: Optimize hotplugging routines

- Power down the slowest cpu
- Move checks from callback to calling function
- Clean it up a bit
msm: hotplug: Add pm ops
msm: hotplug: Fix symbol export
msm: hotplug: Fixup sysfs interface

* Use proper return values
* Fix store_down_lock_duration()
* Add some more checks
* Cleanup some mess
msm: hotplug: Update threshold values and down lock duration

* Power up additional cpus earlier
* Power down cpus later
* Keep cpus online at least 5 seconds
Revert "mm: Increase Dirty Ratios"

This reverts commit eb05cbac2d7e30fe16d447d25549055dcce3f5b9.
Revert "fs: Drop VFS Cache Pressure"

This reverts commit c59d58689ed7b95ab2cb80e56a808a8bb4233780.
Revert "fs: sync: add missing return if fsync is disabled from userspace."

This reverts commit c9587e60bf202456ff6e8f400b4125f3be3adb30.
Revert "fs: sync: enable fsync by default."

This reverts commit 462470bec338abe06eae0eb068f1e5b7a161de73.
Revert "Added fsync on/off support."

This reverts commit 1a7a089d8280166569caa40cbb7015342a0dd264.