Current logic looks like this:
rc = ima_must_measure(NULL, inode, MAY_READ, FILE_CHECK);
if (rc < 0)
goto out;
if (mode & FMODE_WRITE) {
if (inode->i_readcount)
send_tomtou = true;
goto out;
}
if (atomic_read(&inode->i_writecount) > 0)
send_writers = true;
Lets assume we have a policy which states that all files opened for read
by root must be measured.
Lets assume the file has permissions 777.
Lets assume that root has the given file open for read.
Lets assume that a non-root process opens the file write.
The non-root process will get to ima_counts_get() and will check the
ima_must_measure(). Since it is not supposed to measure it will goto
out.
We should check the i_readcount no matter what since we might be causing
a ToMToU voilation!
This is close to correct, but still not quite perfect. The situation
could have been that root, which was interested in the mesurement opened
and closed the file and another process which is not interested in the
measurement is the one holding the i_readcount ATM. This is just overly
strict on ToMToU violations, which is better than not strict enough...
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently for every removed inode IMA must take a global lock and search
the IMA rbtree looking for an associated integrity structure. Instead
we explicitly mark an inode when we add an integrity structure so we
only have to take the global lock and do the removal if it exists.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since finding a struct ima_iint_cache requires a valid struct inode, and
the struct ima_iint_cache is supposed to have the same lifetime as a
struct inode (technically they die together but don't need to be created
at the same time) we don't have to worry about the ima_iint_cache
outliving or dieing before the inode. So the refcnt isn't useful. Just
get rid of it and free the structure when the inode is freed.
Signed-off-by: Eric Paris <eapris@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
IMA always allocates an integrity structure to hold information about
every inode, but only needed this structure to track the number of
readers and writers currently accessing a given inode. Since that
information was moved into struct inode instead of the integrity struct
this patch stops allocating the integrity stucture until it is needed.
Thus greatly reducing memory usage.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
IMA currently allocated an inode integrity structure for every inode in
core. This stucture is about 120 bytes long. Most files however
(especially on a system which doesn't make use of IMA) will never need
any of this space. The problem is that if IMA is enabled we need to
know information about the number of readers and the number of writers
for every inode on the box. At the moment we collect that information
in the per inode iint structure and waste the rest of the space. This
patch moves those counters into the struct inode so we can eventually
stop allocating an IMA integrity structure except when absolutely
needed.
This patch does the minimum needed to move the location of the data.
Further cleanups, especially the location of counter updates, may still
be possible.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
IMA tracks the number of struct files which are holding a given inode
readonly and the number which are holding the inode write or r/w. It
needs this information so when a new reader or writer comes in it can
tell if this new file will be able to invalidate results it already made
about existing files.
aka if a task is holding a struct file open RO, IMA measured the file
and recorded those measurements and then a task opens the file RW IMA
needs to note in the logs that the old measurement may not be correct.
It's called a "Time of Measure Time of Use" (ToMToU) issue. The same is
true is a RO file is opened to an inode which has an open writer. We
cannot, with any validity, measure the file in question since it could
be changing.
This patch attempts to use the i_writecount field to track writers. The
i_writecount field actually embeds more information in it's value than
IMA needs but it should work for our purposes and allow us to shrink the
struct inode even more.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently IMA used the iint->mutex to protect the i_readcount and
i_writecount. This patch uses the inode->i_lock since we are going to
start using in inode objects and that is the most appropriate lock.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The IMA flags is an unsigned long but there is only 1 flag defined.
Lets save a little space and make it a char. This packs nicely next to
the array of u8's.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently IMA uses 2 longs in struct inode. To save space (and as it
seems impossible to overflow 32 bits) we switch these to unsigned int.
The switch to unsigned does require slightly different checks for
underflow, but it isn't complex.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The opencount was used to help debugging to make sure that everything
which created a struct file also correctly made the IMA calls. Since we
moved all of that into the VFS this isn't as necessary. We should be
able to get the same amount of debugging out of just the reader and
write count.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The IMA code needs to store the number of tasks which have an open fd
granting permission to write a file even when IMA is not in use. It
needs this information in order to be enabled at a later point in time
without losing it's integrity garantees.
At the moment that means we store a little bit of data about every inode
in a cache. We use a radix tree key'd on the inode's memory address.
Dave Chinner pointed out that a radix tree is a terrible data structure
for such a sparse key space. This patch switches to using an rbtree
which should be more efficient.
Bug report from Dave:
"I just noticed that slabtop was reporting an awfully high usage of
radix tree nodes:
OBJS ACTIVE USE OBJ SIZE SLABS OBJ/SLAB CACHE SIZE NAME
4200331 2778082 66% 0.55K 144839 29 2317424K radix_tree_node
2321500 2060290 88% 1.00K 72581 32 2322592K xfs_inode
2235648 2069791 92% 0.12K 69864 32 279456K iint_cache
That is, 2.7M radix tree nodes are allocated, and the cache itself is
consuming 2.3GB of RAM. I know that the XFS inodei caches are indexed
by radix tree node, but for 2 million cached inodes that would mean a
density of 1 inode per radix tree node, which for a system with 16M
inodes in the filsystems is an impossibly low density. The worst I've
seen in a production system like kernel.org is about 20-25% density,
which would mean about 150-200k radix tree nodes for that many inodes.
So it's not the inode cache.
So I looked up what the iint_cache was. It appears to used for
storing per-inode IMA information, and uses a radix tree for indexing.
It uses the *address* of the struct inode as the indexing key. That
means the key space is extremely sparse - for XFS the struct inode
addresses are approximately 1000 bytes apart, which means the closest
the radix tree index keys get is ~1000. Which means that there is a
single entry per radix tree leaf node, so the radix tree is using
roughly 550 bytes for every 120byte structure being cached. For the
above example, it's probably wasting close to 1GB of RAM...."
Reported-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus:
MIPS: O32 compat/N32: Fix to use compat syscall wrappers for AIO syscalls.
MAINTAINERS: Change list for ioc_serial to linux-serial.
SERIAL: ioc3_serial: Return -ENOMEM on memory allocation failure
MIPS: jz4740: Fix Kbuild Platform file.
MIPS: Repair Kbuild make clean breakage.
If the host is slow in reading data or doesn't read data at all,
blocking write calls not only blocked the program that called write()
but the entire guest itself.
To overcome this, let's not block till the host signals it has given
back the virtio ring element we passed it. Instead, send the buffer to
the host and return to userspace. This operation then becomes similar
to how non-blocking writes work, so let's use the existing code for this
path as well.
This code change also ensures blocking write calls do get blocked if
there's not enough room in the virtio ring as well as they don't return
-EAGAIN to userspace.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
CC: stable@kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Ralf: Michel's original patch only fixed N32; I replicated the same fix
for O32.]
Signed-off-by: Michel Thebeau <michel.thebeau@windriver.com>
Cc: paul.gortmaker@windriver.com
Cc: bruce.ashfield@windriver.com
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
IOC3 is also being used on SGI MIPS systems but this particular driver is
only being used on IA64 systems so linux-mips made no sense as a list. Pat
also thinks linux-serial@vger.kernel.org is the better list.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In this code, 0 is returned on memory allocation failure, even though other
failures return -ENOMEM or other similar values.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression ret;
expression x,e1,e2,e3;
@@
ret = 0
... when != ret = e1
*x = \(kmalloc\|kcalloc\|kzalloc\)(...)
... when != ret = e2
if (x == NULL) { ... when != ret = e3
return ret;
}
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
To: Pat Gefre <pfg@sgi.com>
Cc: kernel-janitors@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1704/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The platform specific files should be included via the platform-y
variable.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Patchwork: https://patchwork.linux-mips.org/patch/1719/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When running make clean, Kbuild doesn't process the .config file, so nothing
generates a platform-y variable. We can get it to descend into the platform
directories by setting $(obj-).
The dec Platform file was unconditionally setting platform-, obliterating
its previous contents and preventing some directories from being cleaned.
This is change to an append operation '+=' to allow cavium-octeon to be
cleaned.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Patchwork: https://patchwork.linux-mips.org/patch/1718/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
kvm reloads the host's fs and gs blindly, however the underlying segment
descriptors may be invalid due to the user modifying the ldt after loading
them.
Fix by using the safe accessors (loadsegment() and load_gs_index()) instead
of home grown unsafe versions.
This is CVE-2010-3698.
KVM-Stable-Tag.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus:
MIPS: Enable ISA_DMA_API config to fix build failure
MIPS: 32-bit: Fix build failure in asm/fcntl.h
MIPS: Remove all generated vmlinuz* files on "make clean"
MIPS: do_sigaltstack() expects userland pointers
MIPS: Fix error values in case of bad_stack
MIPS: Sanitize restart logics
MIPS: secure_computing, syscall audit: syscall number should in r2, not r0.
MIPS: Don't block signals if we'd failed to setup a sigframe
This patch reverts the driver to enabling/disabling the NFC interrupt
mask rather than enabling/disabling the system interrupt. This cleans
up the driver so that it doesn't rely on interrupts being disabled
within the interrupt handler.
For i.MX21 we keep the current behaviour, that is calling
enable_irq/disable_irq_nosync to enable/disable interrupts. This patch
is based on earlier work by John Ogness.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: John Ogness <john.ogness@linutronix.de>
Tested-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus/i2c/2636-rc8' of git://git.fluff.org/bjdooks/linux:
i2c-imx: do not allow interruptions when waiting for I2C to complete
i2c-davinci: Fix TX setup for more SoCs
Add ISA_DMA_API config item and select it when GENERIC_ISA_DMA enabled.
This fixes build failure on allmodconfig like following:
CC sound/isa/es18xx.o
sound/isa/es18xx.c: In function 'snd_es18xx_playback1_prepare':
sound/isa/es18xx.c:501:9: error: implicit declaration of function 'snd_dma_program'
sound/isa/es18xx.c: In function 'snd_es18xx_playback_pointer':
sound/isa/es18xx.c:818:3: error: implicit declaration of function 'snd_dma_pointer'
make[3]: *** [sound/isa/es18xx.o] Error 1
make[2]: *** [sound/isa/es18xx.o] Error 2
make[1]: *** [sub-make] Error 2
make: *** [all] Error 2
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1717/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[Ralf: I changed the patch to explicitly list all files to be deleted out
of paranoia.]
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Patchwork: http://patchwork.linux-mips.org/patch/1590/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Put the original syscall number into ->regs[0] when we leave syscall
with error. Use it in restart logics. Everything else will have
it 0 since we pass through SAVE_SOME on all the ways in. Note that
in places like bad_stack and inllegal_syscall we leave it 0 - it's not
restartable.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1698/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
448cd16 ("Input: evdev - rearrange ioctl handling") broke EVIOCSABS by
checking for the wrong direction bit.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Reported-by: Sven Neumann <s.neumann@raumfeld.com>
Tested-by: Sven Neumann <s.neumann@raumfeld.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
The i2c_imx_trx_complete() function is using
wait_event_interruptible_timeout() to wait for the I2C controller to
signal that it has completed an I2C bus operation. If the process that
causes the I2C operation receives a signal, the wait will be
interrupted, returning an error. It is better to let the I2C operation
finished before handling the signal (i.e. returning into userspace).
It is safe to use wait_event_timeout() instead, because the timeout
will allow the process to exit if the I2C bus hangs. It's also better
to allow the I2C operation to finish, because unacknowledged I2C
operations can cause the I2C bus to hang.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This patch is an improvement to 4bba0fd8d1
which got to mainline a little early.
Sudhakar Rajashekhara explains that at least OMAP-L138 requires MDR mode
settings before DXR for correct behaviour, so load MDR first with
STT cleared and later load again with STT set.
Tested on DM355 connected to Techwell TW2836 and Wolfson WM8985
Signed-off-by: Jon Povey <jon.povey@racelogic.co.uk>
Acked-by: Troy Kisky <troy.kisky@boundarydevices.com>
Tested-by: Sudhakar Rajashekhara <sudhakar.raj@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Fixes cursor corruption in certain cases.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Revert commit 54672386cc
"firewire: ohci: fix up configuration of TI chips".
It caused massive slow-down and data corruption with a TSB82AA2 based
StarTech EC1394B2 ExpressCard and FireWire 800 harddisks.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/657081http://thread.gmane.org/gmane.linux.kernel.firewire.user/4013
The fact that some card EEPROMs do not program these enhancements may be
related to TSB81BA3 phy chip errata, if not to bugs of TSB82AA2 itself.
We could re-add these configuration steps, but only conditional on a
whitelist of cards on which these enhancements bring a proven positive
effect.
Reported-and-tested-by: Eric Shattow <lucent@gmail.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org> 2.6.35
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
When a driver module is unloaded and the last still open file is a raw
MIDI device, the card and its devices will be actually freed in the
snd_card_file_remove() call when that file is closed. Afterwards, rmidi
and rmidi->card point into freed memory, so the module pointer is likely
to be garbage.
(This was introduced by commit 9a1b64caac82aa02cb74587ffc798e6f42c6170a.)
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-by: Krzysztof Foltman <wdev@foltman.com>
Cc: 2.6.30-2.6.35 <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Fixes build for me... these are what's tested in byteorder.h...
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit a7f8388e accidentally removed it... Al explains:
"Sorry, reordering breakage. In the signals tree here I have
static inline void sig_set_blocked(struct sigset_t *set)
...
and it's used all over the place (including quite a few places where
we currently have sigprocmask(SIG_SETMASK, set, NULL), which is what
it's equivalent to). With that done, m32r doesn't use _BLOCKABLE
anywhere, so it got removed. And that chunk got picked when I'd been
reordering the queue to pull the arch-specific fixes in front.
Sorry."
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We currently have a kernel internal type called aligned_u64 which aligns
__u64's on 8 bytes boundaries even on systems which would normally align
them on 4 byte boundaries. This patch creates a new type __aligned_u64
which does the same thing but which is exposed to userspace rather than
being kernel internal.
[akpm: merge early as both the net and audit trees want this]
[akpm@linux-foundation.org: enhance the comment describing the reasons for using aligned_u64. Via Andreas and Andi.]
Based-on-patch-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: Jan Engelhardt <jengelh@medozas.de>
Cc: David Miller <davem@davemloft.net>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
