commit 946e51f2bf37f1656916eb75bd0742ba33983c28 upstream.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ben Hutchings <ben@decadent.org.uk>
[hujianyang: Backported to 3.10 refer to the work of Ben Hutchings in 3.2:
 - Apply name changes in all the different places we use d_alias and d_child
 - Move the WARN_ON() in __d_free() to d_free() as we don't have dentry_free()]
Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 0db59e59299f0b67450c5db21f7f316c8fb04e84 upstream.

As it is, we have debugfs_remove() racing with symlink traversals.
Supply ->evict_inode() and do freeing there - inode will remain
pinned until we are done with the symlink body.

And rip the idiocy with checking if dentry is positive right after
we'd verified debugfs_positive(), which is a stronger check...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 776164c1faac4966ab14418bb0922e1820da1d19 upstream.

debugfs_remove_recursive() is wrong,

1. it wrongly assumes that !list_empty(d_subdirs) means that this
   dir should be removed.

   This is not that bad by itself, but:

2. if d_subdirs does not becomes empty after __debugfs_remove()
   it gives up and silently fails, it doesn't even try to remove
   other entries.

   However ->d_subdirs can be non-empty because it still has the
   already deleted !debugfs_positive() entries.

3. simple_release_fs() is called even if __debugfs_remove() fails.

Suppose we have

	dir1/
		dir2/
			file2
		file1

and someone opens dir1/dir2/file2.

Now, debugfs_remove_recursive(dir1/dir2) succeeds, and dir1/dir2 goes
away.

But debugfs_remove_recursive(dir1) silently fails and doesn't remove
this directory. Because it tries to delete (the already deleted)
dir1/dir2/file2 again and then fails due to "Avoid infinite loop"
logic.

Test-case:

	#!/bin/sh

	cd /sys/kernel/debug/tracing
	echo 'p:probe/sigprocmask sigprocmask' >> kprobe_events
	sleep 1000 < events/probe/sigprocmask/id &
	echo -n >| kprobe_events

	[ -d events/probe ] && echo "ERR!! failed to rm probe"

And after that it is not possible to create another probe entry.

With this patch debugfs_remove_recursive() skips !debugfs_positive()
files although this is not strictly needed. The most important change
is that it does not try to make ->d_subdirs empty, it simply scans
the whole list(s) recursively and removes as much as possible.

Link: http://lkml.kernel.org/r/20130726151256.GC19472@redhat.com

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Modify the request_module to prefix the file system type with "fs-"
and add aliases to all of the filesystems that can be built as modules
to match.

A common practice is to build all of the kernel code and leave code
that is not commonly needed as modules, with the result that many
users are exposed to any bug anywhere in the kernel.

Looking for filesystems with a fs- prefix limits the pool of possible
modules that can be loaded by mount to just filesystems trivially
making things safer with no real cost.

Using aliases means user space can control the policy of which
filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf
with blacklist and alias directives.  Allowing simple, safe,
well understood work-arounds to known problematic software.

This also addresses a rare but unfortunate problem where the filesystem
name is not the same as it's module name and module auto-loading
would not work.  While writing this patch I saw a handful of such
cases.  The most significant being autofs that lives in the module
autofs4.

This is relevant to user namespaces because we can reach the request
module in get_fs_type() without having any special permissions, and
people get uncomfortable when a user specified string (in this case
the filesystem type) goes all of the way to request_module.

After having looked at this issue I don't think there is any
particular reason to perform any filtering or permission checks beyond
making it clear in the module request that we want a filesystem
module.  The common pattern in the kernel is to call request_module()
without regards to the users permissions.  In general all a filesystem
module does once loaded is call register_filesystem() and go to sleep.
Which means there is not much attack surface exposed by loading a
filesytem module unless the filesystem is mounted.  In a user
namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT,
which most filesystems do not set today.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reported-by: Kees Cook <keescook@google.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

This is to fix up a build problem with a wireless driver due to the
dynamic-debug patches in this branch.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We already initialize it to NULL when declaring it, no need to do
that twice.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch technically breaks userspace, but I suspect that anyone who
actually used this flag would have encountered this brokenness, declared
it lunacy, and already sent a patch.

Signed-off-by: Dave Reisner <dreisner@archlinux.org>
Reviewed-by: Vasiliy Kulikov <segoon@openwall.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

inode->i_private is promised to be NULL on allocation, no need to set it
explicitly.

Signed-off-by: Yan Hong <clouds.yan@gmail.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull user namespace changes from Eric Biederman:
 "This is a mostly modest set of changes to enable basic user namespace
  support.  This allows the code to code to compile with user namespaces
  enabled and removes the assumption there is only the initial user
  namespace.  Everything is converted except for the most complex of the
  filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs,
  nfs, ocfs2 and xfs as those patches need a bit more review.

  The strategy is to push kuid_t and kgid_t values are far down into
  subsystems and filesystems as reasonable.  Leaving the make_kuid and
  from_kuid operations to happen at the edge of userspace, as the values
  come off the disk, and as the values come in from the network.
  Letting compile type incompatible compile errors (present when user
  namespaces are enabled) guide me to find the issues.

  The most tricky areas have been the places where we had an implicit
  union of uid and gid values and were storing them in an unsigned int.
  Those places were converted into explicit unions.  I made certain to
  handle those places with simple trivial patches.

  Out of that work I discovered we have generic interfaces for storing
  quota by projid.  I had never heard of the project identifiers before.
  Adding full user namespace support for project identifiers accounts
  for most of the code size growth in my git tree.

  Ultimately there will be work to relax privlige checks from
  "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing
  root in a user names to do those things that today we only forbid to
  non-root users because it will confuse suid root applications.

  While I was pushing kuid_t and kgid_t changes deep into the audit code
  I made a few other cleanups.  I capitalized on the fact we process
  netlink messages in the context of the message sender.  I removed
  usage of NETLINK_CRED, and started directly using current->tty.

  Some of these patches have also made it into maintainer trees, with no
  problems from identical code from different trees showing up in
  linux-next.

  After reading through all of this code I feel like I might be able to
  win a game of kernel trivial pursuit."

Fix up some fairly trivial conflicts in netfilter uid/git logging code.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits)
  userns: Convert the ufs filesystem to use kuid/kgid where appropriate
  userns: Convert the udf filesystem to use kuid/kgid where appropriate
  userns: Convert ubifs to use kuid/kgid
  userns: Convert squashfs to use kuid/kgid where appropriate
  userns: Convert reiserfs to use kuid and kgid where appropriate
  userns: Convert jfs to use kuid/kgid where appropriate
  userns: Convert jffs2 to use kuid and kgid where appropriate
  userns: Convert hpfs to use kuid and kgid where appropriate
  userns: Convert btrfs to use kuid/kgid where appropriate
  userns: Convert bfs to use kuid/kgid where appropriate
  userns: Convert affs to use kuid/kgid wherwe appropriate
  userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids
  userns: On ia64 deal with current_uid and current_gid being kuid and kgid
  userns: On ppc convert current_uid from a kuid before printing.
  userns: Convert s390 getting uid and gid system calls to use kuid and kgid
  userns: Convert s390 hypfs to use kuid and kgid where appropriate
  userns: Convert binder ipc to use kuids
  userns: Teach security_path_chown to take kuids and kgids
  userns: Add user namespace support to IMA
  userns: Convert EVM to deal with kuids and kgids in it's hmac computation
  ...

Pull driver core merge from Greg Kroah-Hartman:
 "Here is the big driver core update for 3.7-rc1.

  A number of firmware_class.c updates (as you saw a month or so ago),
  and some hyper-v updates and some printk fixes as well.  All patches
  that are outside of the drivers/base area have been acked by the
  respective maintainers, and have all been in the linux-next tree for a
  while.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'driver-core-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits)
  memory: tegra{20,30}-mc: Fix reading incorrect register in mc_readl()
  device.h: Add missing inline to #ifndef CONFIG_PRINTK dev_vprintk_emit
  memory: emif: Add ifdef CONFIG_DEBUG_FS guard for emif_debugfs_[init|exit]
  Documentation: Fixes some translation error in Documentation/zh_CN/gpio.txt
  Documentation: Remove 3 byte redundant code at the head of the Documentation/zh_CN/arm/booting
  Documentation: Chinese translation of Documentation/video4linux/omap3isp.txt
  device and dynamic_debug: Use dev_vprintk_emit and dev_printk_emit
  dev: Add dev_vprintk_emit and dev_printk_emit
  netdev_printk/netif_printk: Remove a superfluous logging colon
  netdev_printk/dynamic_netdev_dbg: Directly call printk_emit
  dev_dbg/dynamic_debug: Update to use printk_emit, optimize stack
  driver-core: Shut up dev_dbg_reatelimited() without DEBUG
  tools/hv: Parse /etc/os-release
  tools/hv: Check for read/write errors
  tools/hv: Fix exit() error code
  tools/hv: Fix file handle leak
  Tools: hv: Implement the KVP verb - KVP_OP_GET_IP_INFO
  Tools: hv: Rename the function kvp_get_ip_address()
  Tools: hv: Implement the KVP verb - KVP_OP_SET_IP_INFO
  Tools: hv: Add an example script to configure an interface
  ...