xref: /OK3568_Linux_fs/kernel/arch/arm64/lib/error-inject.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun 
3*4882a593Smuzhiyun #include <linux/error-injection.h>
4*4882a593Smuzhiyun #include <linux/kprobes.h>
5*4882a593Smuzhiyun 
override_function_with_return(struct pt_regs * regs)6*4882a593Smuzhiyun void override_function_with_return(struct pt_regs *regs)
7*4882a593Smuzhiyun {
8*4882a593Smuzhiyun 	/*
9*4882a593Smuzhiyun 	 * 'regs' represents the state on entry of a predefined function in
10*4882a593Smuzhiyun 	 * the kernel/module and which is captured on a kprobe.
11*4882a593Smuzhiyun 	 *
12*4882a593Smuzhiyun 	 * When kprobe returns back from exception it will override the end
13*4882a593Smuzhiyun 	 * of probed function and directly return to the predefined
14*4882a593Smuzhiyun 	 * function's caller.
15*4882a593Smuzhiyun 	 */
16*4882a593Smuzhiyun 	instruction_pointer_set(regs, procedure_link_pointer(regs));
17*4882a593Smuzhiyun }
18*4882a593Smuzhiyun NOKPROBE_SYMBOL(override_function_with_return);
19