Locking init improvement:
- introduce and use __SPIN_LOCK_UNLOCKED for array initializations,
to pass in the name string of locks, used by debugging
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix check for bad address; use macro instead of open-coding two checks.
Taken from RHEL4 kernel update.
From: Ernie Petrides <petrides@redhat.com>
For background, the BAD_ADDR() macro should return TRUE if the address is
TASK_SIZE, because that's the lowest address that is *not* valid for
user-space mappings. The macro was correct in binfmt_aout.c but was wrong
for the "equal to" case in binfmt_elf.c. There were two in-line validations
of user-space addresses in binfmt_elf.c, which have been appropriately
converted to use the corrected BAD_ADDR() macro in the patch you posted
yesterday. Note that the size checks against TASK_SIZE are okay as coded.
The additional changes that I propose are below. These are in the error
paths for bad ELF entry addresses once load_elf_binary() has already
committed to exec'ing the new image (following the tearing down of the
task's original address space).
The 1st hunk deals with the interp-side of the outer "if". There were two
problems here. The printk() should be removed because this path can be
triggered at will by a bogus interpreter image created and used by a
malicious user. Further, the error code should not be ENOEXEC, because that
causes the loop in search_binary_handler() to continue trying other exec
handlers (twice, in fact). But it's too late for this to work correctly,
because the user address space has already been torn down, and an exec()
failure cannot be returned to the user code because the code no longer
exists. The only recovery is to force a SIGSEGV, but it's best to terminate
the search loop immediately. I somewhat arbitrarily chose EINVAL as a
fallback error code, but any error returned by load_elf_interp() will
override that (but this value will never be seen by user-space).
The 2nd hunk deals with the non-interp-side of the outer "if". There were
two problems here as well. The SIGSEGV needs to be forced, because a prior
sigaction() syscall might have set the associated disposition to SIG_IGN.
And the ENOEXEC should be changed to EINVAL as described above.
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Ernie Petrides <petrides@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This fixes a bug in fs/nfs which makes it impossible to build nfs
without having procfs enabled.
Signed-off-by: Dominik Hackl <dominik@hackl.dhs.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes buggy behaviour of UFS
in such kind of scenario:
open(, O_TRUNC...)
ftruncate(, 1024)
ftruncate(, 0)
Such a scenario causes ufs_panic and remount read-only. This happen
because of according to specification UFS should always allocate block for
last byte, and many parts of our implementation rely on this, but
`ufs_truncate' doesn't care about this.
To make possible return error code and to know about old size, this patch
removes `truncate' from ufs inode_operations and uses `setattr' method to
call ufs_truncate.
Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a rq_sendfile_ok flag to svc_rqst which will be cleared in the privacy
case so that the wrapping code will get copies of the read data instead of
real page cache pages. This makes life simpler when we encrypt the response.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Since nfsv4 actually keeps around the file descriptors it gets from open
(instead of just using them for a single read or write operation), we need to
make sure that we can do RDWR opens and not just RDONLY/WRONLY.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These tests always returned true; clearly that wasn't what was intended.
In keeping with kernel style, make them functions instead of macros while
we're at it.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In the event that lookup_one_len() fails in nfsd_link(), fh_unlock() is
skipped and locks are held overlong.
Patch was tested on 2.6.17-rc2 by causing lookup_one_len() to fail and
verifying that fh_unlock() gets called appropriately.
Signed-off-by: David M. Richter <richterd@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We're checking nfs_in_grace here a few times when there isn't really any
reason to--bad_stateid is probably the more sensible return value anyway.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In the typical v2/v3 case the only new filehandles used as arguments to
operations are filehandles taken directly off the wire, which don't get
dentries until fh_verify() is called.
But in v4 the filehandles that are arguments to operations were often created
by previous operations (putrootfh, lookup, etc.) using fh_compose, which sets
the dentry in the filehandle without calling nfsd_setuser().
This also means that, for example, if filesystem B is mounted on filesystem A,
and filesystem A is exported without root-squashing, then a client can bypass
the rootsquashing on B using a compound that starts at a filehandle in A,
crosses into B using lookups, and then does stuff in B.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
nfsd tries to return to a client the same sort of filehandle as was used by
the client. This removes some filehandle aliasing issues and means that a
server upgrade followed by a downgrade will not confused clients not restarted
during that time.
However when crossing a mountpoint, the filehandle used for one filesystem
doesn't provide any useful information on what sort of filehandle should be
used on the other, and can provide misleading information. So if the
reference filehandle is on a different filesystem to the one being generated,
ignore it.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There is a perfectly valid situation where fh_update gets called on an already
uptodate filehandle - in nfsd_create_v3 where a CREATE_UNCHECKED finds an
existing file and wants to just set the size.
We could possible optimise out the call in that case, but the only harm
involved is that fh_update prints a warning, so it is easier to remove the
warning.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Type '3' is used for the fsid in filehandles when the device number of the
device holding the filesystem has more than 8 bits in either major or minor.
Unfortunately expkey_parse doesn't recognise type 3. Fix this.
(Slighty modified from Frank's original)
Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Just testing the i_sb isn't really enough, at least the vfsmnt must be the
same. Thanks Al.
Cc: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a new security hook definition for the sys_ioprio_get operation. At
present, the SELinux hook function implementation for this hook is
identical to the getscheduler implementation but a separate hook is
introduced to allow this check to be specialized in the future if
necessary.
This patch also creates a helper function get_task_ioprio which handles the
access check in addition to retrieving the ioprio value for the task.
Signed-off-by: David Quigley <dpquigl@tycho.nsa.gov>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The remaining counters in page_state after the zoned VM counter patches
have been applied are all just for show in /proc/vmstat. They have no
essential function for the VM.
We use a simple increment of per cpu variables. In order to avoid the most
severe races we disable preempt. Preempt does not prevent the race between
an increment and an interrupt handler incrementing the same statistics
counter. However, that race is exceedingly rare, we may only loose one
increment or so and there is no requirement (at least not in kernel) that
the vm event counters have to be accurate.
In the non preempt case this results in a simple increment for each
counter. For many architectures this will be reduced by the compiler to a
single instruction. This single instruction is atomic for i386 and x86_64.
And therefore even the rare race condition in an interrupt is avoided for
both architectures in most cases.
The patchset also adds an off switch for embedded systems that allows a
building of linux kernels without these counters.
The implementation of these counters is through inline code that hopefully
results in only a single instruction increment instruction being emitted
(i386, x86_64) or in the increment being hidden though instruction
concurrency (EPIC architectures such as ia64 can get that done).
Benefits:
- VM event counter operations usually reduce to a single inline instruction
on i386 and x86_64.
- No interrupt disable, only preempt disable for the preempt case.
Preempt disable can also be avoided by moving the counter into a spinlock.
- Handling is similar to zoned VM counters.
- Simple and easily extendable.
- Can be omitted to reduce memory use for embedded use.
References:
RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=113512330605497&w=2
RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=114988082814934&w=2
local_t http://marc.theaimsgroup.com/?l=linux-kernel&m=114991748606690&w=2
V2 http://marc.theaimsgroup.com/?t=115014808400007&r=1&w=2
V3 http://marc.theaimsgroup.com/?l=linux-kernel&m=115024767022346&w=2
V4 http://marc.theaimsgroup.com/?l=linux-kernel&m=115047968808926&w=2
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Conversion of nr_bounce to a per zone counter
nr_bounce is only used for proc output. So it could be left as an event
counter. However, the event counters may not be accurate and nr_bounce is
categorizing types of pages in a zone. So we really need this to also be a
per zone counter.
[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Conversion of nr_unstable to a per zone counter
We need to do some special modifications to the nfs code since there are
multiple cases of disposition and we need to have a page ref for proper
accounting.
This converts the last critical page state of the VM and therefore we need to
remove several functions that were depending on GET_PAGE_STATE_LAST in order
to make the kernel compile again. We are only left with event type counters
in page state.
[akpm@osdl.org: bugfixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Conversion of nr_writeback to per zone counter.
This removes the last page_state counter from arch/i386/mm/pgtable.c so we
drop the page_state from there.
[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This makes nr_dirty a per zone counter. Looping over all processors is
avoided during writeback state determination.
The counter aggregation for nr_dirty had to be undone in the NFS layer since
we summed up the page counts from multiple zones. Someone more familiar with
NFS should probably review what I have done.
[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Conversion of nr_page_table_pages to a per zone counter
[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Allows reclaim to access counter without looping over processor counts.
- Allows accurate statistics on how many pages are used in a zone by
the slab. This may become useful to balance slab allocations over
various zones.
[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Ingo Molnar
Chuck Ebbert
Dominik Hackl
Vladimir Saveliev
Evgeniy Dushistov
Linus Torvalds
J. Bruce Fields
David M. Richter
NeilBrown
Frank Filz
David Quigley
Christoph Lameter