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  1. 11 4月, 2013 1 次提交
  3. 09 4月, 2013 3 次提交
  5. 06 4月, 2013 4 次提交
  7. 04 4月, 2013 1 次提交
  9. 02 4月, 2013 1 次提交
    • R
      cs5535-mfgpt: Add another reset method · 945480b1
      由 Richard Weinberger 提交于 
      The CS5535/CS5536 MFGPT has no support to reset the device.
The current method uses an undocumented bit but does not work on all
devices. At least on my ALIX board it completely freezes the board.

This new method tries to soft reset all timers by unconfiguring them.
But this does not clear the RO setup register and therefore it has to
be ignored while probing.

Resetting the timers is not only needed on broken BIOSes also when
kexec is used. Otherwise the new kernel will find preconfigured timers
and odd things will happen.
Signed-off-by: NRichard Weinberger <richard@nod.at>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      945480b1
  11. 29 3月, 2013 16 次提交
  13. 26 3月, 2013 2 次提交
  15. 16 3月, 2013 11 次提交
  17. 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