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Subjectkeyboard driver function hijacking

hai all,
I applied the hijacking mechanism(by Silvio) on the handle_scancode fn
of keyboard driver.It worked fine. I want to open a /proc file(which was created by
another program) , to read its contents on pressing certain key.
But if I press that perticular key ,system is hanging and printing In
Interrupt Handler not --syncing.
Is there any other way to perform the above task.
Below is the code written:


static char original_handle_scancode[CODESIZE];
static char acct_code[CODESIZE] =
"\xb8\x00\x00\x00\x00" /* movl $0,%eax */
"\xff\xe0" /* jmp *%eax */
;

void (*handle_scancode) (unsigned char, int) =
(void (*)(unsigned char, int)) 0xc01b0cd0;

void _handle_scancode(unsigned char scancode, int keydown)
{
static int myflag = 0;
int value,i;


int length_read1;

char buffer1[250];
struct file * f1 = NULL;
mm_segment_t orig_fs1;

file_to_read1 = "/proc/procfs_example/bar"; */

/*
* Restore first bytes of the original handle_scancode code. Call
* the restored function and re-restore the jump code. Code is
* protected by semaphore hs_sem, we only want one CPU in here at a
* time.
*/
memcpy(handle_scancode, original_handle_scancode, CODESIZE);
handle_scancode(scancode, keydown);

if(scancode == 0x19 )
{
f1 = filp_open(file_to_read1, O_RDONLY, 00);

if (!f1 || !f1->f_op || !f1->f_op->read)
{
printk(KERN_ALERT "WARNING: File (read) object is a null pointer!!!\n");
}
f1->f_pos = 0;


/* Use get_fs() and set_fs() to temporarily modify the addr_limit
field of the current task_struct. This will allow the read to
use a buffer whose address is not in use space.
*/
orig_fs1 = get_fs();
set_fs(KERNEL_DS);

length_read1 = f1->f_op->read(f1, buffer1, sizeof(buffer1), &f1->f_pos);

/* Release the file object pointer. */
fput(f1);

printk("<1> The string read from the /proc file is : %s\n",buffer1);

memcpy(handle_scancode, acct_code, CODESIZE);
}

static int __init copymodule_init(void)
{

*(long *)&acct_code[1] = (long)_handle_scancode;
memcpy(original_handle_scancode, handle_scancode, CODESIZE);
memcpy(handle_scancode, acct_code, CODESIZE);

char * file_to_read1 = kmalloc(20, GFP_KERNEL);
return 0;
}




Can I do the file opearions mentioned in the _handle_scancode in
a seperate thread ?

Any suggestions are welcome.
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