Issue
Is it possible to execute shell command in kernel module. I know that we can do it in user space C code using system
subroutine.
I am debugging a kernel module which has memory leak issue. After doing insmod and rmmod module.ko in an infinite loop, system goes out of memory within few minutes with 8G RAM.
It would be helpful to know memory status using free
command before and after the call to API responsible to free memory so i can know that API is working or not.
This is the way i am debugging. Please share if there is any other way to do so.
Solution
You can use call_usermodehelper
function. See the example of how to use it at the LXR#1 or LXR#2.
UPD:
argv[0] = "/bin/bash";
argv[1] = "-c";
argv[2] = "/usr/bin/free";
argv[3] = NULL;
envp[0] = "HOME=/";
envp[1] = "TERM=linux";
envp[2] = "PATH=/sbin:/usr/sbin:/bin:/usr/bin";
envp[3] = NULL;
call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
Answered By - Ilya Matveychikov Answer Checked By - Katrina (WPSolving Volunteer)