SIP off on mac os but still cant load my kext

Question

i,m new to kext programming so my problem is:

i,m running macOS 10.11.6 i have turned SIP off but when i try to load my kext using kextload and using the -v flag i get that my kext was successfully loaded:

*Requesting load of /private/tmp/kern.kext.
/private/tmp/kern.kext loaded successfully (or already loaded).*

and to check that my kext was loaded i have used kextstat :

 152    0 0xffffff7f82db3000 0x2000     0x2000     com.SPX.kext.kern (1) 299868F4-9962-362D-AE3D-09579B6780DB <4>

but when i tail my kernel logs from: /var/log/system.log using the command : tail -f /var/log/system.log

i see that error:

MacBook-Pro com.apple.kextd[47]: kext signature failure override

allowing invalid signature -67050 0xFFFFFFFFFFFEFA16 for kext

"/private/tmp/kern.kext"

my kext is a simple hello world kext and there's my code

#include <mach/mach_types.h>
#include <libkern/libkern.h>

kern_return_t kern_start(kmod_info_t * ki, void *d);
kern_return_t kern_stop(kmod_info_t *ki, void *d);

kern_return_t kern_start(kmod_info_t * ki, void *d)
{
    printf("hello world");
    return KERN_SUCCESS;
}

kern_return_t kern_stop(kmod_info_t *ki, void *d)
{
    printf("bye kext");
    return KERN_SUCCESS;
}

thanks in advance for any help

edit:

so after many test its look like the kext was loaded successfully but when it comes to the code sign issue i went through Xcode Build Settings and there i found code signing so in the code signing there's code signing identity so i set it to Don't code sign and i build it with using Xcode build tool xcodebuild -configuration Debug -target kern but still no progress till now, so i hope someone help at least give a link or anything .

The messages you're quoting sound like the kernel let you load regardless of the incorrect signature. — zneak, Oct 26 '16 at 22:16
But actually the system.log should give the output not the error that I have mentioned above — yazan daba, Oct 26 '16 at 22:26
You're missing the newline character (\n) from your print calls, which is probably why you can't see the output. — pmdj, Oct 29 '16 at 07:19
Sir I cant thank you enough sir you're more than awesome thank you sooo much please set as answer to get the point or that correct sign (I,m new to SOF — yazan daba, Oct 29 '16 at 16:05

score 0 · Accepted Answer · answered Oct 30 '16 at 13:30

The output you're getting suggests that the kext is being loaded - code signing is not your problem.

I do notice however that your printf() calls contain no line termination. (\n) Not outputting whole lines will cause the messages to be buffered for longer than you'd expect, and run into other messages. With something like this, it should work, and you should see your messages in the system log:

printf("hello world\n");

SIP off on mac os but still cant load my kext

1 Answers1