This makes several changes but they're in one function and sort of
related:
"buf" was leaked on error. The leak if we try to read an invalid
length is the main concern because it could be triggered over and
over.
If the copy_to_user() failed, then the original code returned the
number of bytes remaining. read() is supposed to be the opposite way,
where we return the number of bytes copied. I changed it to just return
-EFAULT on errors.
Also I changed the debug output from "-EFAULT" to just "<fail>" because
it isn't -EFAULT necessarily. And since we go though that path if the
length is invalid now, there was another debug print that I removed.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
We shouldn't unlock here. I think this was a cut and paste error.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (505 commits)
[media] af9015: Fix max I2C message size when used with tda18271
[media] IR: initialize ir_raw_event in few more drivers
[media] Guard a divide in v4l1 compat layer
[media] imon: fix nomouse modprobe option
[media] imon: remove redundant change_protocol call
[media] imon: fix my egregious brown paper bag w/rdev/idev split
[media] cafe_ccic: Configure ov7670 correctly
[media] ov7670: allow configuration of image size, clock speed, and I/O method
[media] af9015: support for DigitalNow TinyTwin v3 [1f4d:9016]
[media] af9015: map DigitalNow TinyTwin v2 remote
[media] DigitalNow TinyTwin remote controller
[media] af9015: RC fixes and improvements
videodev2.h.xml: Update to reflect the latest changes at videodev2.h
[media] v4l: document new Bayer and monochrome pixel formats
[media] DocBook/v4l: Add missing formats used on gspca cpia1 and sn9c2028
[media] firedtv: add parameter to fake ca_system_ids in CA_INFO
[media] tm6000: fix a macro coding style issue
tm6000: Remove some ugly debug code
[media] Nova-S-Plus audio line input
[media] [RFC,1/1] V4L2: Use new CAP bits in existing RDS capable drivers
...
Fixes an oops when an lirc driver that doesn't provide its own fops is
unplugged while the lirc cdev is open. Tested with lirc_igorplugusb,
with a special thanks to Timo Boettcher for providing the test hardware.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Can't explain it (yet), but I've seen the 'get irctl via private_data'
setup fail for a number of people (ioctl called before its filled in?),
so lets go back to a variant of the old way, but one that still works
with unlocked_ioctl.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
If an lirc device driver doesn't specify its own fops, we set set
ir->cdev.owner to THIS_MODULE. If it does specify its own fops, we
set ir->cdev.owner to ir->d.owner. Subsequent module_{get,put} calls
should be using ir->cdev.owner, not ir->d.owner.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Use names that clearly identify functions as lirc functions.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
As pointed out (and tested) by Joris van Rantwijk, we do actually need
to wire up .compat_ioctl for 32-bit lirc userspace to work with 64-bit
lirc kernelspace. Do it. And add a check to make sure we get a valid
irctl in the ioctl handler.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
>From Joris van Rantwijk <jorispubl@xs4all.nl>:
I tested lirc_serial and found that it works fine.
Except the LIRC ioctls do not work in my 64-bit-kernel/32-bit-user
setup. I added compat_ioctl entries in the drivers to fix this.
While doing so, I noticed inconsistencies in the argument type of
the LIRC ioctls. All ioctls are declared in lirc.h as having argument
type __u32, however there are a few places where the driver calls
get_user/put_user with an unsigned long argument.
The patch below changes lirc_dev and lirc_serial to use __u32 for all
ioctl arguments, and adds compat_ioctl entries.
It should probably also be done in the other low-level drivers,
but I don't have hardware to test those.
I've dropped the .compat_ioctl addition from Joris' original patch,
as I swear the non-compat definition should now work for both 32-bit
and 64-bit userspace. Technically, I think we still need/want a
in getting a reply to you).
Reported-by: Joris van Rantwijk <jorispubl@xs4all.nl>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
There does not seem to be a need for lirc to
allow seeking on the file descriptor, so let's
just disallow this before users start relying
on it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The lirc userspace needs all the current ioctls defined, and we need to
put the header files in places out-of-tree and/or staging lirc drivers
(which I plan to prep soon) can easily build with. I've actually tested this
in a tree w/all the lirc drivers queued up to be submitted for staging. I'm
also reasonably sure that Andy Walls is going to need most of the ioctls
anyway for his cx23888 IR driver work.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
New code should not rely on the big kernel lock,
so use the unlocked_ioctl file operation in lirc.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
On Wed, Jul 07, 2010 at 02:52:58PM +0200, Jiri Slaby wrote:
> Hi,
>
> stanse found a locking error in lirc_dev_fop_read:
> if (mutex_lock_interruptible(&ir->irctl_lock))
> return -ERESTARTSYS;
> ...
> while (written < length && ret == 0) {
> if (mutex_lock_interruptible(&ir->irctl_lock)) { #1
> ret = -ERESTARTSYS;
> break;
> }
> ...
> }
>
> remove_wait_queue(&ir->buf->wait_poll, &wait);
> set_current_state(TASK_RUNNING);
> mutex_unlock(&ir->irctl_lock); #2
>
> If lock at #1 fails, it beaks out of the loop, with the lock unlocked,
> but there is another "unlock" at #2.
This should do the trick. Completely untested beyond compiling, but its
not exactly a complicated fix, and in practice, I'm not aware of anyone
ever actually tripping that locking bug, so there's zero functional change
in typical use here.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
v2: currently unused ioctls are included, but #if 0'd out
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Dan Carpenter