I have a question about changing the page attributes of the system call table.
I am writing a kernel module that does some system call interposition. This works fine on my debian system, but apparently the stock Fedora kernel (2.6.22) has the system call table write protected. So I would like the module to add write permissions to the system call table before it modifies it. This is the code in my init_module that is problematic: // Storing the original call orig_kill = sys_call_table[__NR_kill]; // Change to write pg = virt_to_page(sys_call_table); change_page_attr(pg, 1, PAGE_KERNEL); global_flush_tlb(); // Test write, should change nothing, but oopses instead sys_call_table[__NR_kill] = (void*)orig_kill; I imagine that I'm doing something obviously wrong; I've only been looking at kernel code for a couple weeks. Can someone please explain what my error is? -Hajime Inoue - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
