Impact: fix crash on reading from /sys/module/.../ieee80211_default_rc_algo

The module_param type "charp" simply sets a char * pointer in the
module to the parameter in the commandline string: this is why we keep
the (mangled) module command line around.  But when set via sysfs (as
about 11 charp parameters can be) this memory is freed on the way
out of the write().  Future reads hit random mem.

So we kstrdup instead: we have to check we're not in early commandline
parsing, and we have to note when we've used it so we can reliably
kfree the parameter when it's next overwritten, and also on module
unload.

(Thanks to Randy Dunlap for CONFIG_SYSFS=n fixes)
Reported-by: NSitsofe Wheeler <sitsofe@yahoo.com>
Diagnosed-by: NFrederic Weisbecker <fweisbec@gmail.com>
Tested-by: NFrederic Weisbecker <fweisbec@gmail.com>
Tested-by: NChristof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

There are a lot of one-liner uses of __setup() in the kernel: they're
cumbersome and not queryable (definitely not settable) via /sys.  Yet
it's ugly to simplify them to module_param(), because by default that
inserts a prefix of the module name (usually filename).

So, introduce a "core_param".  The parameter gets no prefix, but
appears in /sys/module/kernel/parameters/ (if non-zero perms arg).  I
thought about using the name "core", but that's more common than
"kernel".  And if you create a module called "kernel", you will die
a horrible death.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

The kparam code tries to handle over-length parameter prefixes at
runtime.  Not only would I bet this has never been tested, it's not
clear that truncating names is a good idea either.

So let's check at compile time.  We need to move the #define to
moduleparam.h to do this, though.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

On alpha, ia64 and ppc64 only relocations to local data can go into
read-only sections. The vast majority of module parameters use the global
generic param_set_*/param_get_* functions, so the 'const' attribute for
struct kernel_param is not only useless, but it also causes compile
failures due to 'section type conflict' in those rare cases where
param_set/get are local functions.

This fixes http://bugzilla.kernel.org/show_bug.cgi?id=8964Signed-off-by: NIvan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove the deprecated __attribute_used__.

[Introduce __section in a few places to silence checkpatch /sam]
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

.. in an effort to make read-only whatever can be made, so that
CONFIG_DEBUG_RODATA can catch as many issues as possible.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Globally, s/driverfs/sysfs/g.
Signed-off-by: NRobert P. J. Day <rpjday@mindspring.com>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Fix source files to build with CONFIG_SYSFS=n.
module_subsys is not available.

SYSFS=n, MODULES=y:	T:y
SYSFS=n, MODULES=n:	T:y

SYSFS=y, MODULES=y:	T:y
SYSFS=y, MODULES=n:	T:y
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

One of the mistakes a module_param() user can make is to supply default
value of module parameter as the last argument.  module_param() accepts
permissions instead.  If default value is, say, 3 (-------wx), parameter
becomes world-writeable.

So far, the only remedy was to apply grep(1) and read drivers submitted
to -mm. BTDT.

With this patch applied, compiler will finally do some job.

*) bounds checking on permissions
*) world-writeable bit checking on permissions
*) compile breakage if checks trigger

First version of this check (only "& 2" part) directly caught 4 out of 7
places during my last grep.

    Subject: Neverending module_param() bugs
    [X] drivers/acpi/sbs.c:101:module_param(capacity_mode, int, CAPACITY_UNIT);
    [X] drivers/acpi/sbs.c:102:module_param(update_mode, int, UPDATE_MODE);
    [ ] drivers/acpi/sbs.c:103:module_param(update_info_mode, int, UPDATE_INFO_MODE);
    [ ] drivers/acpi/sbs.c:104:module_param(update_time, int, UPDATE_TIME);
    [ ] drivers/acpi/sbs.c:105:module_param(update_time2, int, UPDATE_TIME2);
    [X] drivers/char/watchdog/sbc8360.c:203:module_param(timeout, int, 27);
    [X] drivers/media/video/tuner-simple.c:13:module_param(offset, int, 0666);
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

param_array() in kernel/params.c can now become static.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Now when kbuild passes KBUILD_MODNAME with "" do not __stringify it when
used. Remove __stringnify for all users.
This also fixes the output of:

$ ls -l /sys/module/
drwxr-xr-x 4 root root 0 2006-01-05 14:24 pcmcia
drwxr-xr-x 4 root root 0 2006-01-05 14:24 pcmcia_core
drwxr-xr-x 3 root root 0 2006-01-05 14:24 "processor"
drwxr-xr-x 3 root root 0 2006-01-05 14:24 "psmouse"

The quoting of the module names will be gone again.
Thanks to GregKH + Kay Sievers for reproting this.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!