linux.git/fs/hppfs, branch v3.10

hppfs: get rid of ->fsync()

2013-04-29T19:41:42+00:00

it has grown by accident - directories there do *not* use page cache, so
there's nothing to write.

Signed-off-by: Al Viro

hppfs: fix the leaks on close()

2013-04-29T19:41:41+00:00

we need to close the underlying procfs file and free ->private_data

Signed-off-by: Al Viro

fs: Limit sys_mount to only request filesystem modules.

2013-03-04T03:36:31+00:00

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 
Acked-by: Kees Cook 
Reported-by: Kees Cook 
Signed-off-by: "Eric W. Biederman"

new helper: file_inode(file)

2013-02-23T04:31:31+00:00

Signed-off-by: Al Viro

pidns: Use task_active_pid_ns where appropriate

2012-11-19T13:59:09+00:00

The expressions tsk->nsproxy->pid_ns and task_active_pid_ns
aka ns_of_pid(task_pid(tsk)) should have the same number of
cache line misses with the practical difference that
ns_of_pid(task_pid(tsk)) is released later in a processes life.

Furthermore by using task_active_pid_ns it becomes trivial
to write an unshare implementation for the the pid namespace.

So I have used task_active_pid_ns everywhere I can.

In fork since the pid has not yet been attached to the
process I use ns_of_pid, to achieve the same effect.

Signed-off-by: Eric W. Biederman

hppfs: fix the return value of get_inode()

2012-10-09T20:34:52+00:00

In case of error, the function get_inode() returns ERR_PTR().
But the users hppfs_lookup() and hppfs_fill_super() use NULL
test for check the return value, not IS_ERR(), so we'd better
change the return value of get_inode() to NULL instead of
ERR_PTR().

dpatch engine is used to generated this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun 
Signed-off-by: Richard Weinberger

um: get rid of pointless include "..." where include <...> will do

2012-10-09T20:28:45+00:00

Signed-off-by: Al Viro 
Signed-off-by: Richard Weinberger

switch dentry_open() to struct path, make it grab references itself

2012-07-22T20:01:29+00:00

Signed-off-by: Al Viro

stop passing nameidata to ->lookup()

2012-07-14T12:34:32+00:00

Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument.  And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...

Signed-off-by: Al Viro

vfs: Rename end_writeback() to clear_inode()

2012-05-06T05:43:41+00:00

After we moved inode_sync_wait() from end_writeback() it doesn't make sense
to call the function end_writeback() anymore. Rename it to clear_inode()
which well says what the function really does - set I_CLEAR flag.

Signed-off-by: Jan Kara 
Signed-off-by: Fengguang Wu