want to edit your boot.img?
included files in zip: mkbootimg (i compiled this file from android source), unpack-bootimg.pl, repack-bootimg.pl
i edited the repack script to compile the nexus s img correctly.
Code:
--base 0x30000000 --pagesize 4096
first dump original boot.img:
Code:
cat /dev/mtd/mtd2 > /sdcard/boot.img
then drag/drop to your linux box to edit file.
use unpack script:
Code:
./unpack-bootimg.pl boot.img
you will end up with 2 compressed files and 1 folder.
finished editing and want to repack boot.img, for example:
Code:
./repack-bootimg.pl <kernel> <ramdisk-directory> <outfile>
most info and scripts pulled from here: http://android-dls.com/wiki/index.php?title=HOWTO:_Unpack,_Edit,_and_Re-Pack_Boot_Images, thanks to the original author.
test your new boot.img:
Code:
fastboot boot boot.img
Two things:
1. if you have any bad blocks in your boot partition, this method will fail to extract the boot.img (you need to skip bad blocks, but cat will just get an error)
2. you can replace just the kernel (leaving the ramdisk and parameters intact) using:
Code:
% fastboot flash zimage zImage
The bootloader will read-modify-write the boot partition, replacing the kernel only.
how would you skip bad blocks? i never thought of a phone as having bad blocks.
k0mpresd said:
i never thought of a phone as having bad blocks.
Click to expand...
Click to collapse
All flash devices can have bad blocks. But it usually isn't something the end user would notice, unless there are so many and something is wrong that you're losing drive space.
edit: more info here if your curious http://en.wikipedia.org/wiki/Flash_memory
hmm, very strange thing happening to me. I've only gotten my boot.img to compile and boot successfully once with this method, but now I can't seem to get it to compile? I keep getting errors of the file name or file type. I'm using the correct usage.. If I compile manually with mkbootimg on the cmd line it'll compile but it won't boot. Just bootloops at the Google splash..
Jroid try my Matr1x kernel and see what happens
Sent from my Nexus S using XDA App
The problem seems to be compiling the boot with the perl scripts, not the kernel itself.
Try manually:
Once unpacked do the boot.img-ramdisk.cpio.gz with the following command (moved to the ramdisk folder):
Code:
#sudo find . | cpio -o -H newc | gzip > ../<your boot name>.img-ramdisk.cpio.gz
Then cd ../
And repack:
Code:
#./mkbootimg --kernel <your boot name>.img-kernel.gz --ramdisk <your boot name>.img-ramdisk.cpio.gz --base 0x30000000 --pagesize 4096 -o boot.img
you can replace just the kernel (leaving the ramdisk and parameters intact) using:
Code:
% fastboot flash zimage zImage
The bootloader will read-modify-write the boot partition, replacing the kernel only.
Click to expand...
Click to collapse
It won't work on the Nexus S.
python08 said:
It won't work on the Nexus S.
Click to expand...
Click to collapse
exactly, i'd love to be able to do this for some testing but it doesn't allow me.
EDIT: yes it does. Swetland is right
Chamb' said:
Try manually:
Once unpacked do the boot.img-ramdisk.cpio.gz with the following command (moved to the ramdisk folder):
Code:
#sudo find . | cpio -o -H newc | gzip > ../<your boot name>.img-ramdisk.cpio.gz
Then cd ../
And repack:
Code:
#./mkbootimg --kernel <your boot name>.img-kernel.gz --ramdisk <your boot name>.img-ramdisk.cpio.gz --base 0x30000000 --pagesize 4096 -o boot.img
Click to expand...
Click to collapse
I've tied compiling a boot both manually (with cmdline) and with the perl scripts and have used a simple kernel.gz and ramdisk.cpio.gz for my file names.. doesn't really matter what I name it as long as it has the correct file format in this .gz and .cpio.gz right? the manual compile goes fine with base 0x30000000 and pagesize 4096
however, it does not boot and will bootloop at the Google splash
Used boot.img extracted from (what ROM ?) cat /dev/mtd/mtd2 ?
Is the phone start with this boot.img (unchanged) if you flash it by typing "fastboot flash..." ?
After that, just try to unpack and repack the boot.img without changes on ramdisk or kernel, if it works that means your changes suck (^^).
These commands (or perl scripts) work perfectly for me.
Lol I will try doing that. The boot.img I used is from stock 2.3.4, edited the ramdisk (specifically init.rc & init.herring.rc)
Like I said, first time I used the perl scripts I edited my ramdisk, threw in a netarchy kernel, it compiled fine and booted. Now if I use the perl script to repack with an aosp kernel, it gives me an error about file name and/or extension being wrong. Or complains it can't find mkbootimg when its there and executable. I'll re run it again and post errors
Sent from my Nexus S
he guys where is the boot image located? not the animation, the google logo at the start of the booting!
Sent from my Nexus S using XDA Premium App
ok so when I used the repack-bootimg.pl script, it kept giving me this error:
Code:
boot.img-kernel.gz Not a directory at ./repack-bootimg.pl line 13.
So I ran mkbootimg manually, without a cmdline comment as stated above. It compiled
and booted beautifully all stock with no init.rc or init.herring.rc edits.
however when I compile a boot.img coupled with a stock kernel and a modified ramdisk, I get a non-booting boot.img. One came out at 2.9 mb and the other at 5.6 mb neither boots using the same cmd that compiled the working boot. Must be my edits.. I literally only changed about 1 line in init.rc and another line in init.herring.rc that causing it not to boot.
By the way, I got some info on a stock boot.img using the unpackbootimg binary (not the perl script) and here's what it outputs:
Code:
#BOARD_KERNEL_CMDLINE console=ttyFIQ0 no_console_suspend
BOARD_KERNEL_BASE 30000000
BOARD_PAGE_SIZE 00001000
I enter that pagesize and it says it's not a valid value when I compile boot.img's
Borky_16 said:
he guys where is the boot image located? not the animation, the google logo at the start of the booting!
Sent from my Nexus S using XDA Premium App
Click to expand...
Click to collapse
part of the kernel
to change-https://github.com/morfic/Samsung-logo
ogdobber said:
part of the kernel
to change-https://github.com/morfic/Samsung-logo
Click to expand...
Click to collapse
yeah i know thanks for the link a helping source though!
Sent from my Nexus S using XDA Premium App
Sorry for the Control C Control V of it, but I just found this topic now..
I`m facing this problem when I try to unpack boot.img..
I have done it 2 days ago but dunno why, now I can`t..
Follows what is happening..
Code:
[email protected]:~/NS-bootwork$ ./unpack-bootimg.pl boot.img
Found a secondary file after the ramdisk image.
According to the spec (mkbootimg.h) this file can exist,
but this script is not designed to deal with this scenario.
The Kernel is built, as a zImage and the WLAN as a bmc3429.ko..
Just repeating, I have built this Kernel 2 days ago in the same way, without any problems, but now I`m struggling on the message after inputting ./unpack-bootimg.pl boot.img..
Dunno what else to try, I re-downloaded the unpack-bootimg.pl from 2 different sources, and still the same error..
Any ideas?
Many thanks..
P.S.: Ubuntu 11.04 x64..
EDIT
Well, I already solve it!
That is what I did..
As unpack-bootimg.pl was not working (don`t know why) I used split_bootimg.pl script, splitting the boot.img and created new ramdisk img..
Code:
./split_bootimg.pl boot.img
mkdir ramdisk
cd ramdisk
gzip -dc ../boot.img-ramdisk.gz | cpio -i
find . | cpio -o -H newc | gzip > ../newramdisk.cpio.gz
Then after just compiled the Kernel with
Code:
./mkbootimg --kernel zImage --ramdisk newramdisk.cpio.gz --base 0x30000000 --pagesize 4096 --cmdline _console_suspend=1 console=bull's -o newtestboot.img'no
Witches includes " --cmdline _console_suspend=1 console=bull's" to not break BT functionality, in the case of Nexus S..
I found the tools here work well: http://glandium.org/blog/?p=2214
...if you then use the code originally posted above:
Code:
sudo find . | cpio -o -H newc | gzip > ../<your boot name>.img-ramdisk.cpio.gz
./mkbootimg --kernel <your boot name>.img-kernel.gz --ramdisk <your boot name>.img-ramdisk.cpio.gz --base 0x30000000 --pagesize 4096 -o boot.img
Related
Hi,
There seems to me to be the general idea that swapping kernels is just flashing a different boot.img, however, what seems to never be mentioned is that each boot.img has a unique ram disk or included set of files/folder structure. This ram disk was designed to work with a specific version of android and within that, a specific build of that version. The init.rc file could be totally different, there could be a different init compiled in, ro.secure could be 0 in default.prop, and so on.
When looking through some of the scripts out there, it is always flash boot.img, not extract the ramdisk and rebuilt boot.img first. This introduces a tad bit of randomness to the whole kernel swapping scenario.
This is an pseudo example of what I would do, if I had to swap kernels manually on the phone. I have attached the referenced phone compatible binaries. (I would normally do it from within linux on a PC)
With CWM running on your phone, start adb.
$ adb shell
# ~ cd /tmp
# /tmp dump_image /dev/block/mmcblk0p11 boot.img
# /tmp unpack boot.img
# /tmp ls
boot.img boot.img-zImage boot.img-ramdisk
# /tmp cp /sdcard/mynewkernel-zImage .
# /tmp ls
boot.img boot.img-zImage boot.img-ramdisk mynewkernel-zImage
# /tmp cat /proc/cmdline >cmdline.txt
# /tmp cat ./cmdline.txt
[email protected] [email protected] vmalloc=320M video=tegrafb console=null usbcore.old_scheme_first=1 tegraboot=sdmmc tegrapart=mbr:1100:100:800,kpanic:2500:400:800 security=tomoyo mot_prod=1 androidboot.serialno=TA2xxxxxxx
# /tmp busybox vi cmdline.txt
# /tmp cat ./cmdline.txt
[email protected] [email protected] [email protected] vmalloc=320M video=tegrafb console=null usbcore.old_scheme_first=1 tegraboot=sdmmc tegrapart=mbr:1100:100:800,kpanic:2500:400:800 security=tomoyo mot_prod=1 androidboot.serialno=TA2xxxxxxx
# /tmp mkbootimg --cmdline cmdline.txt --kernel mynewkernel-zImage --ramdisk boot.img-ramdisk.gz -o boot.img
# /tmp flash_image /dev/block/mmcblk0p11 boot.img
the bits in green if you wanted to fix the missing [email protected] in your cmdline if applicable.
Replace the general sequence in your CWM install scripts when all you want is to swap the kernel, not potentially change the boot sequence/flags as well.
Cheers!
hi
thanks for tutorial
but regarding this command :
Code:
/tmp cp /sdcard/mynewkernel-zImage
what is mynewkernel-zImage ?
Hazem62 said:
hi
thanks for tutorial
but regarding this command :
Code:
/tmp cp /sdcard/mynewkernel-zImage
what is mynewkernel-zImage ?
Click to expand...
Click to collapse
That would be whatever kernel image you wanted to replace your existing kernel with. As the ones around are in zip files with prepackaged boot.img files you would have to unzip and extract to get just the kernel part. Also, you would need any dependent libs copied over to /system/lib/[modules].
This is nothing really new, just not being done with the Atrix thus far.
Cheers!
How do I get boot.img-ramdisk from this step
NFHimself said:
# /tmp ls
boot.img boot.img-zImage boot.img-ramdisk
Click to expand...
Click to collapse
into boot.img-ramdisk.gz for mkbootimg? do I use the regular gzip?
NFHimself said:
# /tmp mkbootimg --cmdline cmdline.txt --kernel mynewkernel-zImage --ramdisk boot.img-ramdisk.gz -o boot.img
Click to expand...
Click to collapse
If I wanted to edit and change the partition table, could I use the same method to pull and edit the partition file since it also exists in the same directory as cmdline?
toyota86 said:
do I use the regular gzip?
Click to expand...
Click to collapse
Yes.
(deleted)
NFHimself said:
Hi,
There seems to me to be the general idea that swapping kernels is just flashing a different boot.img, however, what seems to never be mentioned is that each boot.img has a unique ram disk or included set of files/folder structure. This ram disk was designed to work with a specific version of android and within that, a specific build of that version. The init.rc file could be totally different, there could be a different init compiled in, ro.secure could be 0 in default.prop, and so on.
When looking through some of the scripts out there, it is always flash boot.img, not extract the ramdisk and rebuilt boot.img first. This introduces a tad bit of randomness to the whole kernel swapping scenario.
This is an pseudo example of what I would do, if I had to swap kernels manually on the phone. I have attached the referenced phone compatible binaries. (I would normally do it from within linux on a PC)
With CWM running on your phone, start adb.
$ adb shell
# ~ cd /tmp
# /tmp dump_image /dev/block/mmcblk0p11 boot.img
# /tmp unpack boot.img
# /tmp ls
boot.img boot.img-zImage boot.img-ramdisk
# /tmp cp /sdcard/mynewkernel-zImage .
# /tmp ls
boot.img boot.img-zImage boot.img-ramdisk mynewkernel-zImage
# /tmp cat /proc/cmdline >cmdline.txt
# /tmp cat ./cmdline.txt
[email protected] [email protected] vmalloc=320M video=tegrafb console=null usbcore.old_scheme_first=1 tegraboot=sdmmc tegrapart=mbr:1100:100:800,kpanic:2500:400:800 security=tomoyo mot_prod=1 androidboot.serialno=TA2xxxxxxx
# /tmp busybox vi cmdline.txt
# /tmp cat ./cmdline.txt
[email protected] [email protected] [email protected] vmalloc=320M video=tegrafb console=null usbcore.old_scheme_first=1 tegraboot=sdmmc tegrapart=mbr:1100:100:800,kpanic:2500:400:800 security=tomoyo mot_prod=1 androidboot.serialno=TA2xxxxxxx
# /tmp mkbootimg --cmdline cmdline.txt --kernel mynewkernel-zImage --ramdisk boot.img-ramdisk.gz -o boot.img
# /tmp flash_image /dev/block/mmcblk0p11 boot.img
the bits in green if you wanted to fix the missing [email protected] in your cmdline if applicable.
Replace the general sequence in your CWM install scripts when all you want is to swap the kernel, not potentially change the boot sequence/flags as well.
Cheers!
Click to expand...
Click to collapse
can any1 tell me how to extract boot.img-zimage for adding more drivers
Ni5hant said:
can any1 tell me how to extract boot.img-zimage for adding more drivers
Click to expand...
Click to collapse
Basically, you can't.
New drivers are either built into the kernel when it is compiled. Or built as kernel modules using the same kernel source and same compiler as the main kernel. In both cases, you need to know all about compiling a kernel.
runekock said:
Basically, you can't.
New drivers are either built into the kernel when it is compiled. Or built as kernel modules using the same kernel source and same compiler as the main kernel. In both cases, you need to know all about compiling a kernel.
Click to expand...
Click to collapse
anyway ..i have an ARM kali 2.0 on my galaxy j7.. and i want to connect my TP-Link Tw722n wifi adapter to it....
"Dmesg | grep usb" shows the usb...bt i cant anything else with it..........any help would be appreciated
Ni5hant said:
anyway ..i have an ARM kali 2.0 on my galaxy j7.. and i want to connect my TP-Link Tw722n wifi adapter to it....
"Dmesg | grep usb" shows the usb...bt i cant anything else with it..........any help would be appreciated
Click to expand...
Click to collapse
If you are running Kali Linux on a Galaxy J7, then you are in entirely the wrong thread. This is about Android on Motorola Atrix. Try asking in a Kali Linux thread. Though I suspect the answer will be more or less the same -- that you need to learn how to compile a kernel to do anything.
runekock said:
If you are running Kali Linux on a Galaxy J7, then you are in entirely the wrong thread. This is about Android on Motorola Atrix. Try asking in a Kali Linux thread. Though I suspect the answer will be more or less the same -- that you need to learn how to compile a kernel to do anything.
Click to expand...
Click to collapse
Thnx for the answer buddy i have downloaded my kernel source and goind to recompile it...just looking for the right toolchain to download...anyways thnx for the replies
Ni5hant said:
Thnx for the answer buddy i have downloaded my kernel source and goind to recompile it...just looking for the right toolchain to download...anyways thnx for the replies
Click to expand...
Click to collapse
BTW, this may not only be a question of drivers. The userspace networking code also needs to setup the new network port.
runekock said:
BTW, this may not only be a question of drivers. The userspace networking code also needs to setup the new network port.
Click to expand...
Click to collapse
Nopp..i have to just enable aethros driver support with cfg80211 module..and after flash dat kernel next time i can use my usb wifi adapter...although at this kernel i cant use my inbuilt wifi adapter...anyways i have. Build my kernel have to just compile it...if it will be a success i will upload it...
Hi All,
I am working on MotoX kernel(3.4.42) , after compilation of kernel source code i am able to generate zImage. I have written zImage to original boot.img using following command
$ abootimg -u boot.img -k zImage
with this boot.img(with custom zImage) I flashed using following command
$fastboot flash boot boot.img
After booting my MotoX phone , my touch screen is not responding. I observed touch screen I2c driver is not initilized because device tree image(dt.img) is not loading by zImage during booting .
Can any one please help how to create dt.img with compiled dtb files and flash in to device???????
Thanks
Ram
516
Any one any help???????
ram1443 said:
Any one any help???????
Click to expand...
Click to collapse
im really surprised you expected most people to know the answer to your question. anyways you can rip t he prebuilt dtb from you stock boot.img using these tools right here : https://github.com/xiaolu/mkbootimg_tools and then use them to repack your zimage. abootimg isnt useful in its current form it seems.
if you wish to compile the dts files into dtb ones youll need to run a script on them, here is teh guide that taught me how to http://www.wiki.xilinx.com/Build+Device+Tree+Blob
shabbypenguin said:
im really surprised you expected most people to know the answer to your question. anyways you can rip t he prebuilt dtb from you stock boot.img using these tools right here : https://github.com/xiaolu/mkbootimg_tools and then use them to repack your zimage. abootimg isnt useful in its current form it seems.
if you wish to compile the dts files into dtb ones youll need to run a script on them, here is teh guide that taught me how to http://www.wiki.xilinx.com/Build+Device+Tree+Blob
Click to expand...
Click to collapse
Hi shabbypenguin,
Thanks for your help,
Now i am able to boot with my custom zImage and default dt.img afeter following above links. but i am unable to generate custom dt.img from my compiled dtb files.
To generate dt.img i am doing below steps:
COMMAND:
-------------
$ ./dtbTool -s 2048 -o ./dt.img -p ../../source/kernel_kitkat/out/target/product/generic/obj/kernel/scripts/dtc/ ../../source/kernel_kitkat/out/target/product/generic/obj/kernel/arch/arm/boot/
OUTPUT :
-----------
Input directory: '../../source/kernel_kitkat/out/target/product/generic/obj/kernel/arch/arm/boot/'
Output file: 'dt.img'
Found file: msm8960ab-ultra-maxx-p1.dtb ... skip, failed to scan for 'qcom,msm-id = <' tag
Found file: msm8960ab-ultram-p3.dtb ... skip, failed to scan for 'qcom,msm-id = <' tag
=> Found 0 unique DTB(s)
Can you please guide me how to generate dt.img from compiled dtb files??
Thanks
Ram
Greetings
I followed these procedures, and pushed the boot.img with Odin, but the phone goes into download mode stating: "Could not do normal boot." Can anyone see what I am doing wrong? How can I troubleshoot the issue? Is there some way I can look at some logs somewhere? I did save my recovery.log file from twrp to the sdcard before I loaded the backedup files and rebooted the phone. I put them here is there anything else I can do?
I tried the same thing with boot.img and I got the following:
Code:
[email protected]:~/xiaolu/mkbootimg_tools$ ./mkboot boot.img ksumag
Unpack & decompress boot.img to ksumag
kernel : zImage
ramdisk : ramdisk
page size : 2048
kernel size : 8262680
ramdisk size : 1064985
dtb size : 1300480
base : 0x00000000
kernel offset : 0x00008000
ramdisk offset : 0x02000000
second_offset : 0x00f00000
tags offset : 0x01e00000
dtb img : dt.img
cmd line : console=null androidboot.hardware=qcom user_debug=31 msm_rtb.filter=0x37 ehci-hcd.park=3
ramdisk is gzip format.
Unpack completed.
[email protected]:~/xiaolu/mkbootimg_tools$ cd ksumag/
[email protected]:~/xiaolu/mkbootimg_tools/ksumag$ ls
dt.img img_info ramdisk ramdisk.gz zImage
[email protected]:~/xiaolu/mkbootimg_tools/ksumag$
I put the scsi_wait.ko ( name? ) file in ramdisk /dev folder, and replaced the zImage and dt.img file with the ones I made, and packed them into my own boot.img file.
Here is the output:
Code:
[email protected]:~/xiaolu/mkbootimg_tools$ ./mkboot ksumag/ boot.img
mkbootimg from ksumag//img_info.
kernel : zImage
ramdisk : new_ramdisk.gz
page size : 2048
kernel size : 8262680
ramdisk size : 1082259
dtb size : 1300480
base : 0x00000000
kernel offset : 0x00008000
ramdisk offset : 0x02000000
tags offset : 0x01e00000
dtb img : dt.img
cmd line : console=null androidboot.hardware=qcom user_debug=31 msm_rtb.filter=0x37 ehci-hcd.park=3
Kernel size: 8262680, new ramdisk size: 1082259, boot.img: 10893312.
boot.img has been created.
...
Then I put all files in a tar file. I did make a couple of mistakes with files names, which I hope did not damage the boot.img file.
Code:
[email protected]:~/xiaolu/mkbootimg_tools$ tar -H ustar -c boot.img >> boot.img
tar: boot.img: file is the archive; not dumped
[email protected]:~/xiaolu/mkbootimg_tools$ ls
ARM dtbToolCM ksumag mkbootimg recovery.img
boot.img dtbtool.txt lz4 MyKernel.tar.md5 recovery.tar.md5
commands dtc mkboot oldfiles shahin
dtbTool ksuamg mkbootfs README.md sm-n900p-test1
[email protected]:~/xiaolu/mkbootimg_tools$ tar -H ustar -c boot.img > boot.img
tar: boot.img: file is the archive; not dumped
[email protected]:~/xiaolu/mkbootimg_tools$ tar -H ustar -c boot.img > boot.tar
[email protected]:~/xiaolu/mkbootimg_tools$
Then I took the hash of the entire thing:
Code:
[email protected]:~/xiaolu/mkbootimg_tools$ md5sum -t boot.tar >> boot.tar
[email protected]:~/xiaolu/mkbootimg_tools$ mv boot.tar boot.tar.md5
[email protected]:~/xiaolu/mkbootimg_tools$
What are you trying to get
kenny1991 said:
What are you trying to get
Click to expand...
Click to collapse
I am trying to get a flashable image. The file I get from the above procedure goes on my phone, but the kernel does not seem to be loaded. I am still learning about the boot process, and I do not know if my phone just has a bootloader or a bootstrap also; regardless it seems to not load the kernel since it goes into download mode. The recovery.log does not show anything either. I posted in pastebin. I can put link to it here if you think it would help. My goal is to flash my phone with a copy of the kernel which I built myself.
Oh you need a developer to respond for that.
kenny1991 said:
Oh you need a developer to respond for that.
Click to expand...
Click to collapse
Do you know if I can move this thread myself or perhaps request it from one of the admins? I do not know how effective it would be if I put a link to this discussion in the developer forum.
You may ask as you can't move it. You should move it to developers discussion forum
Hi all,
I am trying to get an insecure kernel for Nexus 6, marshmallow 6.0, and I stuck at a bootloop.
The AOSP tag android-6.0.0_r1 builds without any errors. Then I flash the produced insecure boot image on a nexus 6, which had the latest 6.0 factory images.
Has anyone managed to do this procedure?
Btw, I am compiling the AOSP sources, and not the kernel sources.
In AOSP, I think, the kernel/zImage is precompiled, and the aosp build system bundles it into a boot image.
So, if someone has managed to build a working insecure boot.img from any marshmallow branch please let me know.
Or has done the same thing from kernels sources, also let me know.
EDIT:
How to compile an insecure kernel:
0. This will use the precompiled kernel found in aosp sources.
So we are not actually compiling. But this title might help some folks googling the topic.
2. modify device/<maker>/<codename>/fstab.<codename>/, and remove verify tag from system
3. make -jN bootimage
Alternatively, you can follow the procedure by ziddey, and removing the verify tag from fstab.shamu, allows the kernel to be booted!
NOTE: insecure kernel is not permissive.
How to compile a permissive kernel:
0. Now we will actually compile the kernel.
1. Download the kernel sources, and checkout the branch you want. Do these modifications.
Finally compile the kernel. (There are many tutorials for kernel compilation online)
2. copy the kernel (arch/arm/boot/zImage-dtb) to your aosp_dir/device/<maker>/<codename>-kernel/
3. Disable verification (as w/ insecure kernel)
4. make -j8 bootimage
How to compile an insecure and permissive kernel:
Not sure about this. I 'd play with configurations in aosp_dir/device/<maker>/<codename>,
or maybe try an eng build. If anyone knows just post it!
I have tried these with the kernel branch "android-msm-shamu-3.10-marshmallow-mr1",
and the aosp tag "android-6.0.1_r21".
I have also tried to unpack and repack the boot.img using unpackbootimg and mkbootimg from https://github.com/osm0sis/mkbootimg.
I have extracted ramdisk, edited the default prob, repacked ramdisk, and packed using:
Code:
mkbootimg --kernel su_boot.img-zImage --ramdisk su_boot.img-ramdisk.gz --cmdline 'console=ttyHSL0,115200,n8 androidboot.console=ttyHSL0 androidboot.hardware=shamu msm_rtb.filter=0x37 ehci-hcd.park=3 utags.blkdev=/dev/block/platform/msm_sdcc.1/by-name/utags utags.backup=/dev/block/platform/msm_sdcc.1/by-name/utagsBackup coherent_pool=8M' --base 00000000 --pagesize 2048 --kernel_offset 00008000 --ramdisk_offset 02000000 --tags_offset 01e00000 --board "" -o ins_su_boot.img
Have I missed anything?
*EDIT* also tried w/ 'abootimg'. Still no luck.
Screwing around with random files found on the internet is not going to solve your problem. Use the program from *AOSP*. And make sure your parameters match (I'm not going to verify them for you). Bootloops are always cute, what did you change? Typically running make bootimg should make you a good bootimg from AOSP sources.
Well, turns out that in this case, that assumption is not correct.
The first issue is that the verity keys are not present in a custom built boot.img. At least not ones without also involving an entire system build (not that they would match the system partition that you already have).
So to solve that, edit the fstab file in the shamu device tree to remove the verify parameter from the system partition. Once that is done, it should no longer randomly reboot.
UNFORTUNATELY, that may not be enough to make the whole thing work properly still, since there appears to be some other differences between the AOSP userdebug's boot.img and the google user build. You will be able to adb in, but the android subsystem won't run.
These utilities I have used were the ones that have been successfully used to pack/unpack boot images by others. I have also done this successfully in the past, for another device running earlier versions.
Yeap. That's the problem. A kernel build from AOSP sources does not work out of the box with the rest of the system, if it is a production build. This used to work for Lollipop, but I guess they tighten security up.
Building zImage from kernel sources is still not a solution for me, as I can't properly pack/unpack a Marshmallow boot.img
The problem might be something very stupid, OS specific, and I don't want to waste any more time on this.
For now I will live with SuperSu and adbd insecure.
Maybe at some point I might try to remove the verification to see whether the rest of the stuff play nicely.
Thanks for your time!
[edit]
Answer is root. http://forum.xda-developers.com/showpost.php?p=64110288&postcount=1283
[/edit]
I spent a while tonight trying to figure this out as well. Simply dumping boot.img and recreating it works fine. But something goes wrong when unpacking/repacking the ramdisk. Stripping bootsize from bootimg.cfg so abootimg recalculates it doesn't help.
1. I did find that mkboot "works": https://github.com/ModdingMyMind/mkbootimg_tools
Simply run `mkboot boot.img boot` to dump to dir boot. Make changes to ramdisk, and then run `mkboot boot newboot.img` to create a new image. However, for whatever reason, this causes at least one issue for me. The sbin dir, despite being 755 in the ramdisk is 750 again in Android. Not sure what's going on here since I can redump newboot.img and confirm that sbin is 755.
2. I looked at seSuperuser/super-bootimg and found https://github.com/seSuperuser/super-bootimg/blob/master/scripts/bootimg.sh
The relevant part is in doneBootImgEdit(). Looking at the comments, Husson found that appending the changes to the inflated ramdisk cpio and then deflating it works. I just tested this and indeed it does work.
Husson only appends new/changed files; as a test, I tried appending the entire new ramdisk onto the old one, and sure enough, it bugs out again. Will have to investigate why this happening later, but for now, this is good enough.
As well, abootimg also comes with the tools abootimg-pack-initrd and aboot-unpack-initrd, which takes care of gzip/cpio. Of course, since the packing part doesn't work, we can't use it.
So, here's an example. Say you want to change fstab.shamu (to remove /system verification and/or /data forced encryption):
Code:
# extract boot.img
abootimg -x boot.img
# unpack the extracted initrd.img to ramdisk dir
abootimg-unpack-initrd
cd ramdisk
# make your changes to ramdisk/fstab.shamu here....
echo fstab.shamu | cpio -o -H newc > ../initrd2
cd ..
# inflate initrd.img
cp initrd.img initrd.gz
gunzip initrd.gz
# append and create new initrd.img
cat initrd initrd2 |gzip -9 -c > newinitrd.img
# strip bootsize from bootimg.cfg
sed 1d bootimg.cfg > newbootimg.cfg
# create new boot.img
abootimg --create newboot.img -f newbootimg.cfg -k zImage -r newinitrd.img
newboot.img should be a working boot image. If modifying multiple files, it may be easiest to create a different dir with those files and use find . |cpio -o -H newc > ../initrd2
Hope this helps. And if anyone can explain why this is necessary / how to recreate initrd from scratch, I can continue being lazy.
Thanks @phhusson
[edit]
Damn. I tried applying a different init file and it ate ****.
[/edit]
ziddey said:
I spent a while tonight trying to figure this out as well. Simply dumping boot.img and recreating it works fine. But something goes wrong when unpacking/repacking the ramdisk. Stripping bootsize from bootimg.cfg so abootimg recalculates it doesn't help.
1. I did find that mkboot "works": https://github.com/ModdingMyMind/mkbootimg_tools
Simply run `mkboot boot.img boot` to dump to dir boot. Make changes to ramdisk, and then run `mkboot boot newboot.img` to create a new image. However, for whatever reason, this causes at least one issue for me. The sbin dir, despite being 755 in the ramdisk is 750 again in Android. Not sure what's going on here since I can redump newboot.img and confirm that sbin is 755.
2. I looked at seSuperuser/super-bootimg and found https://github.com/seSuperuser/super-bootimg/blob/master/scripts/bootimg.sh
The relevant part is in doneBootImgEdit(). Looking at the comments, Husson found that appending the changes to the inflated ramdisk cpio and then deflating it works. I just tested this and indeed it does work.
Husson only appends new/changed files; as a test, I tried appending the entire new ramdisk onto the old one, and sure enough, it bugs out again. Will have to investigate why this happening later, but for now, this is good enough.
As well, abootimg also comes with the tools abootimg-pack-initrd and aboot-unpack-initrd, which takes care of gzip/cpio. Of course, since the packing part doesn't work, we can't use it.
So, here's an example. Say you want to change fstab.shamu (to remove /system verification and/or /data forced encryption):
Code:
# extract boot.img
abootimg -x boot.img
# unpack the extracted initrd.img to ramdisk dir
abootimg-unpack-initrd
cd ramdisk
# make your changes to ramdisk/fstab.shamu here....
echo fstab.shamu | cpio -o -H newc > ../initrd2
cd ..
# inflate initrd.img
cp initrd.img initrd.gz
gunzip initrd.gz
# append and create new initrd.img
cat initrd initrd2 |gzip -9 -c > newinitrd.img
# strip bootsize from bootimg.cfg
sed 1d bootimg.cfg > newbootimg.cfg
# create new boot.img
abootimg --create newboot.img -f newbootimg.cfg -k zImage -r newinitrd.img
newboot.img should be a working boot image. If modifying multiple files, it may be easiest to create a different dir with those files and use find . |cpio -o -H newc > ../initrd2
Hope this helps. And if anyone can explain why this is necessary / how to recreate initrd from scratch, I can continue being lazy.
Thanks @phhusson
[edit]
Damn. I tried applying a different init file and it ate ****.
[/edit]
Click to expand...
Click to collapse
My guess, and the reason why I tried appending without further thinking, is that the new initramfs files contains SELinux labels, which standard GNU/Linux cpio tool doesn't support.
One would have to investigate the changes in mkbootfs done recently.
Also, I guess mkboot is using Android's mkbootfs, which forces the permissions by itself I think.
Though the fact that extracting back give the result you expected is weird.
In super-bootimg I chose to change init.rc to chmod /sbin
Wow. http://forum.xda-developers.com/showpost.php?p=64110288&postcount=1283
Just tested and sure enough, everything is working.
Thanks @shoey63
Hopefully a final update:
The difference is in ownership. Unpacking (cpio -i) as a regular user will not preserve the ownership. However, repacking (cpio -o) does.
To repack, add -R 0.0 to cpio (i.e. --owner root.root).
e.g.
Code:
find . |cpio -o -H newc -R 0.0 | gzip -9 > ../newinitrd.img
I just tested and this works just fine without being root.
ziddey said:
Hopefully a final update:
The difference is in ownership. Unpacking (cpio -i) as a regular user will not preserve the ownership. However, repacking (cpio -o) does.
To repack, add -R 0.0 to cpio (i.e. --owner root.root).
e.g.
Code:
find . |cpio -o -H newc -R 0.0 | gzip -9 > ../newinitrd.img
I just tested and this works just fine without being root.
Click to expand...
Click to collapse
Erf that's weird, I'm pretty sure I always ran the script as root...
Anyway, thanks for the info! I'll probably update my scripts with it
I just wanted to post that using root to extract the cpio file fixed the boot failure for me on my Nexus 9 with 6.0.1. You also need to use root to find the files and create the cpio file because some files are only accessible by root of course. I guess that should have been obvious (usually needed for /dev nodes) as @phhusson said, but this time I didn't do that until reading here.
To unpack the boot.img file I used: https://github.com/osm0sis/mkbootimg.git
To pack the boot.img file I used: https://android.googlesource.com/platform/system/core/+/master/mkbootimg
I'm not sure you need the official google packer, but I just happened to use when it worked.
EDIT: I needed to update boot.img and I tried it using the osm0sis packer and it worked.
Hey guys. Thanks for the replies!
I needed a permissive kernel this time, and I have played around with the sources and your recommendations and got it working. :good:
The post by ziddey might be the easiest way to make any kernel bootable, by disabling the verification from fstab.
(and uses just one packing/unpacking tool)
You can do the same thing from sources, again by modifying the fstab on aosp.
You can build an insecure kernel by using the pre-built kernel (is aosp),
or compile and then pack a permissive one.
This procedure wasn't working for me back then when I tried it (hence this thread). I am not sure if it was my fault or the initial marshmallow release had differences from the sources. More info on the first post.
Hello mates!
I've been playing with XT1097's boot.img and need some help as my boot.img fails to boot if I repack ramdisk.
Using abootimg
Extracting boot.img contents:
Code:
abootimg -x boot.img ==> produces bootimg.cfg, initrd.img and zImage files in the current directory
Updating boot.img contents without touching ramdisk (using the one extracted in the previous step):
Code:
abootimg -u boot.img -r initrd.img
If I extract initrd.img and try to repack it, then system fails at boot:
Extracting ramdisk (initrd.img) contents:
Code:
abootimg-unpack-initrd ==> produces a ramdisk subdir
Repacking without modyfing ramdisk folder contents:
Code:
abootimg-pack-initrd newramdisk.img
Updating boot.img with newramdisk.img
Code:
abootimg -u boot.img -r newramdisk.img
Even though the generated boot.img's size matches the original one - 10444800 bytes - system gets stuck at boot logo.
The same issue happens if I use these tools combined:
mkbootimg, unmkbootimg, gzip and cpio
Any ideas are welcome