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  1. 13 12月, 2013 1 次提交
  3. 10 12月, 2013 2 次提交
  5. 15 11月, 2013 1 次提交
  7. 01 10月, 2013 1 次提交
  9. 27 9月, 2013 1 次提交
    • A
      USB: Fix breakage in ffs_fs_mount() · 2606b28a
      由 Al Viro 提交于 
      	There's a bunch of failure exits in ffs_fs_mount() with
seriously broken recovery logics.  Most of that appears to stem
from misunderstanding of the ->kill_sb() semantics; unlike
->put_super() it is called for *all* superblocks of given type,
no matter how (in)complete the setup had been.  ->put_super()
is called only if ->s_root is not NULL; any failure prior to
setting ->s_root will have the call of ->put_super() skipped.
->kill_sb(), OTOH, awaits every superblock that has come from
sget().

Current behaviour of ffs_fs_mount():

We have struct ffs_sb_fill_data data on stack there.  We do
	ffs_dev = functionfs_acquire_dev_callback(dev_name);
and store that in data.private_data.  Then we call mount_nodev(),
passing it ffs_sb_fill() as a callback.  That will either fail
outright, or manage to call ffs_sb_fill().  There we allocate an
instance of struct ffs_data, slap the value of ffs_dev (picked
from data.private_data) into ffs->private_data and overwrite
data.private_data by storing ffs into an overlapping member
(data.ffs_data).  Then we store ffs into sb->s_fs_info and attempt
to set the rest of the things up (root inode, root dentry, then
create /ep0 there).  Any of those might fail.  Should that
happen, we get ffs_fs_kill_sb() called before mount_nodev()
returns.  If mount_nodev() fails for any reason whatsoever,
we proceed to
	functionfs_release_dev_callback(data.ffs_data);

That's broken in a lot of ways.  Suppose the thing has failed in
allocation of e.g. root inode or dentry.  We have
	functionfs_release_dev_callback(ffs);
	ffs_data_put(ffs);
done by ffs_fs_kill_sb() (ffs accessed via sb->s_fs_info), followed by
	functionfs_release_dev_callback(ffs);
from ffs_fs_mount() (via data.ffs_data).  Note that the second
functionfs_release_dev_callback() has every chance to be done to freed memory.

Suppose we fail *before* root inode allocation.  What happens then?
ffs_fs_kill_sb() doesn't do anything to ffs (it's either not called at all,
or it doesn't have a pointer to ffs stored in sb->s_fs_info).  And
	functionfs_release_dev_callback(data.ffs_data);
is called by ffs_fs_mount(), but here we are in nasal daemon country - we
are reading from a member of union we'd never stored into.  In practice,
we'll get what we used to store into the overlapping field, i.e. ffs_dev.
And then we get screwed, since we treat it (struct gfs_ffs_obj * in
disguise, returned by functionfs_acquire_dev_callback()) as struct
ffs_data *, pick what would've been ffs_data ->private_data from it
(*well* past the actual end of the struct gfs_ffs_obj - struct ffs_data
is much bigger) and poke in whatever it points to.

FWIW, there's a minor leak on top of all that in case if ffs_sb_fill()
fails on kstrdup() - ffs is obviously forgotten.

The thing is, there is no point in playing all those games with union.
Just allocate and initialize ffs_data *before* calling mount_nodev() and
pass a pointer to it via data.ffs_data.  And once it's stored in
sb->s_fs_info, clear data.ffs_data, so that ffs_fs_mount() knows that
it doesn't need to kill the sucker manually - from that point on
we'll have it done by ->kill_sb().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NMichal Nazarewicz <mina86@mina86.com>
Cc: stable <stable@vger.kernel.org> # 3.3+
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      2606b28a
  11. 28 8月, 2013 1 次提交
  13. 10 4月, 2013 1 次提交
  15. 04 3月, 2013 1 次提交
    • E
      fs: Limit sys_mount to only request filesystem modules. · 7f78e035
      由 Eric W. Biederman 提交于 
      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: NSerge Hallyn <serge.hallyn@canonical.com>
Acked-by: NKees Cook <keescook@chromium.org>
Reported-by: NKees Cook <keescook@google.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
      7f78e035
  17. 18 1月, 2013 1 次提交
  19. 10 1月, 2013 1 次提交
  21. 31 10月, 2012 1 次提交
    • S
      usb: gadget: always update HS/SS descriptors and create a copy of them · 10287bae
      由 Sebastian Andrzej Siewior 提交于 
      HS and SS descriptors are staticaly created. They are updated during the
bind process with the endpoint address, string id or interface numbers.

After that, the descriptor chain is linked to struct usb_function which
is used by composite in order to serve the GET_DESCRIPTOR requests,
number of available configs and so on.

There is no need to assign the HS descriptor only if the UDC supports
HS speed because composite won't report those to the host if HS support
has not been reached. The same reasoning is valid for SS.

This patch makes sure each function updates HS/SS descriptors
unconditionally and uses the newly introduced helper function to create a
copy the descriptors for the speed which is supported by the UDC.

While at that, also rename f->descriptors to f->fs_descriptors in order
to make it more explicit what that means.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
      10287bae
  23. 27 9月, 2012 1 次提交
  25. 21 9月, 2012 1 次提交
  27. 07 9月, 2012 1 次提交
  29. 04 6月, 2012 1 次提交
  31. 15 5月, 2012 1 次提交
  33. 04 5月, 2012 1 次提交
  35. 11 4月, 2012 2 次提交
  37. 21 3月, 2012 1 次提交
  39. 17 3月, 2012 1 次提交
  41. 24 1月, 2012 1 次提交
  43. 09 1月, 2012 1 次提交
    • A
      functionfs: unfuck failure exits on mount · 5b5f9560
      由 Al Viro 提交于 
      * if you do dput() of root dentry, do *not* follow that with iput() of root
inode.
* while we are at it, don't do that dput() at all - you are leaving the pointer
in ->s_root and your ->kill_sb() will be very unhappy with that.  It will do
proper dput(), though, so the easiest way is to leave that to it entirely.
* freeing ->s_fs_info is also best left to ->kill_sb() (which will do it
anyway), especially since we leave the pointer in place.
* that xchg() in ->kill_sb() is not a bug per se, but it's a plain and simple
masturbation with fewer excuses than Onan had...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      5b5f9560
  45. 12 12月, 2011 1 次提交
  47. 01 11月, 2011 1 次提交
  49. 10 9月, 2011 1 次提交
    • K
      usb gadget: clean up FSF boilerplate text · 28c9fc68
      由 Klaus Schwarzkopf 提交于 
      remove the following two paragraphs as they are not needed:

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
License for more details.

You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc.,59
Temple Place - Suite 330, Boston, MA  02111-1307, USA.
Signed-off-by: NKlaus Schwarzkopf <schwarzkopf@sensortherm.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      28c9fc68
  51. 29 6月, 2011 1 次提交
  53. 05 2月, 2011 1 次提交
  55. 11 12月, 2010 1 次提交
  57. 18 11月, 2010 2 次提交
  59. 17 11月, 2010 3 次提交
  61. 29 10月, 2010 1 次提交
  63. 27 10月, 2010 1 次提交
  65. 26 10月, 2010 1 次提交
    • C
      fs: do not assign default i_ino in new_inode · 85fe4025
      由 Christoph Hellwig 提交于 
      Instead of always assigning an increasing inode number in new_inode
move the call to assign it into those callers that actually need it.
For now callers that need it is estimated conservatively, that is
the call is added to all filesystems that do not assign an i_ino
by themselves.  For a few more filesystems we can avoid assigning
any inode number given that they aren't user visible, and for others
it could be done lazily when an inode number is actually needed,
but that's left for later patches.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      85fe4025
  67. 11 8月, 2010 2 次提交