[MOD] Disable system write protection on stock kernel

[flar2]

This module will disable system write protection on the stock HTC One kernel.


To make /system writeable, you must install the module and then remount /system as rw.

For example:

insmod /system/lib/modules/wp_mod.ko
mount -o remount,rw /system


You can make an init.d script to load it, or add it to the boot.img. Either way will work, but it's important that this is loaded at boot, as attempting to make changes to /system and then installing this module could corrupt the partition.


This is mainly for devs, who are free to incorporate it into their ROMs.
Unless you are an advanced user, I would wait for it to be included in your favourite ROM.


A credit and a link here so people can thank me in the OP would be much appreciated


Download:
wp_mod.ko


Source code: wp_mod.c

 

[:No-Frost:]

Awesome mate... Thanks a lot

 

[Nekromantik]

Thanks!
Quick question, do we need to install the module manually first before I create the init script?

 

[Isotopes]

wp_mod.ko for 3.4.10-gddcfb8c kernel version

wow ... new version from this mod ... thx :highfive:

ok ... installed wp_mod.ko to system/lib/modules ... make a new boot.img ... restart ... modified a file in system ... restart ... but changed file back original

ok ... next try ... i found the mod is kernel depends ... hexedit the mod to my kernel version ... installed ... modified a file ... restart ... and it works now, the file is well modified

thx @flar2

attached my modified wp_mod.ko only for 3.4.10-gddcfb8c kernel-version

use the attached with cwm-recovery, its only the modified wp_mod.ko file

 

[flar2]

The module should be placed somewhere on your /system partition, because that is what is mounted early in the boot process.

Kernel modules are usually located in /system/lib/modules/ but you can put it anywhere on /system

Then you can load it with an init script using the commands I posted above. Or you can put those commands in init.rc in the boot.img. Obviously the command has to be modified to reflect the location where you copied wp_mod.ko

You have to make sure that the boot.img is set to run init.d scripts, this is also done in init.rc.

 

[flar2]

wow ... new version from this mod ... thx :highfive:

ok ... installed wp_mod.ko to system/lib/modules ... make a new boot.img ... restart ... modified a file in system ... restart ... but changed file back original

ok ... next try ... i found the mod is kernel depends ... hexedit the mod to my kernel version ... installed ... modified a file ... restart ... and it works now, the file is well modified

Yes, it will only load if the version info matches.


If people don't know what that means, check your kernel:

uname -a

And make sure the module has the same string:

modinfo wp_mod.ko

You can change it with a hex editor as above, make sure you only change the characters of the version string and nothing else.

 

[torxx]

Good job mate

 

[nikotine81]

Good job mate

Really good job can you do the same file for the kernel? Thanks in advance

 

[Isotopes]

wp_mod.ko for 3.4.10-g87f8d97 kernel version

Really good job can you do the same file for the kernel? Thanks in advance

and now, here the wp_mod.ko for 3.4.10-g87f8d97 kernel version

use the attached with cwm-recovery, its only the modified wp_mod.ko file

 

[nikotine81]

and now, here the wp_mod.ko for 3.4.10-g87f8d97 kernel version

use the attached with cwm-recovery, its only the modified wp_mod.ko file

Thanks i will test

 

[Nekromantik]

and now, here the wp_mod.ko for 3.4.10-g87f8d97 kernel version

use the attached with cwm-recovery, its only the modified wp_mod.ko file

Works fine
Thanks

 

[noob.fl]

Works fine
Thanks

fine is the wrong word, works perfect :good::good::good:

 

[Riyal]

Hi! Just wanted to add additional info. Since the kernel source is out now you could also disable write protection by changing the line in

arch/arm/configs/m7_defconfig

from

CONFIG_MMC_MUST_PREVENT_WP_VIOLATION=y

to

# CONFIG_MMC_MUST_PREVENT_WP_VIOLATION is not set

referencing file

arch/arm/mach-msm/emmc_partitions.c

code

#ifdef CONFIG_MMC_MUST_PREVENT_WP_VIOLATION
		if (!strncmp(ptn->name, "system", 6))
			mmc_blk_set_wp_prevention_partno((int) ptn->offset);
#endif

on

void mmc_blk_set_wp_prevention_partno(int partno)
{
	sprintf(wp_prevention_partno, "mmcblk0p%d", partno);
	pr_info("%s: set wp_prevention_partno to %s\n", __func__, wp_prevention_partno);
}
EXPORT_SYMBOL(mmc_blk_set_wp_prevention_partno);

from

drivers/mmc/card/block.c

 

[Sonic7]

Works great thank you

Sent from my HTC One using xda app-developers app

 

[flar2]

Hi! Just wanted to add additional info. Since the kernel source is out now you could also disable write protection by changing the line in



from

to



referencing file



code

#ifdef CONFIG_MMC_MUST_PREVENT_WP_VIOLATION
		if (!strncmp(ptn->name, "system", 6))
			mmc_blk_set_wp_prevention_partno((int) ptn->offset);
#endif

on

void mmc_blk_set_wp_prevention_partno(int partno)
{
	sprintf(wp_prevention_partno, "mmcblk0p%d", partno);
	pr_info("%s: set wp_prevention_partno to %s\n", __func__, wp_prevention_partno);
}
EXPORT_SYMBOL(mmc_blk_set_wp_prevention_partno);

from

Thank you, I discovered this months ago: http://forum.xda-developers.com/showthread.php?t=2059411. The reason for disabling it via a module is so people can continue to use the stock kernel. There are already custom kernels for this phone, but not everyone wants a custom kernel.

 

[Nekromantik]

Thank you, I discovered this months ago: http://forum.xda-developers.com/showthread.php?t=2059411. The reason for disabling it via a module is so people can continue to use the stock kernel. There are already custom kernels for this phone, but not everyone wants a custom kernel.

Only custom kernel is one from you at the moment.
Have to wait for more devs now.

The base version for the source code seems to be a older base, does that make a difference?

 

[flar2]

Only custom kernel is one from you at the moment.
Have to wait for more devs now.

The base version for the source code seems to be a older base, does that make a difference?

It depends on what they changed.
I thought a couple custom kernels were posted in the trick droid thread?

 

[Nekromantik]

It depends on what they changed.
I thought a couple custom kernels were posted in the trick droid thread?

Only saw one other one but that did not work as it had issues with calls.

 

[Riyal]

Thank you, I discovered this months ago: http://forum.xda-developers.com/showthread.php?t=2059411. The reason for disabling it via a module is so people can continue to use the stock kernel. There are already custom kernels for this phone, but not everyone wants a custom kernel.

Nice! Never had a One X phone so wasn't aware of your mods :fingers-crossed:

 

[flar2]

If you're feeling adventurous here's a kernel to try:

http://goo.im/devs/flar2/One/Bulletproof-m7-0.1.zip


I don't have this device, so I couldn't test it. It might not work.

If the installer doesn't work, take the boot.img out of the zip and flash it in fastboot.

If the kernel won't boot, please send me /proc/last_kmsg. I might have to make some adjustments to the boot.img.

Don't install this unless you want to help me out with log files, etc.