samples/kretprobes: Fix return value if register_kretprobe() failed

Use the actual return value instead of always -1 if register_kretprobe() failed. E.g. without this patch: # insmod samples/kprobes/kretprobe_example.ko func=no_such_func insmod: ERROR: could not insert module samples/kprobes/kretprobe_example.ko: Operation not permitted With this patch: # insmod samples/kprobes/kretprobe_example.ko func=no_such_func insmod: ERROR: could not insert module samples/kprobes/kretprobe_example.ko: Unknown symbol in module Link: https://lkml.kernel.org/r/1635213091-24387-2-git-send-email-yangtiezhu@loongson.cn

Tiezhu Yang committed 5 years ago

Commit f76fbbb1 parent 010db091 file · +1 −1Browse files

Unified · Split

samples/kprobes/kretprobe_example.c+1−1

@@ -86,7 +86,7 @@ static int __init kretprobe_init(void) · 85 unmodified lines
86	ret = register_kretprobe(&my_kretprobe);	86	ret = register_kretprobe(&my_kretprobe);
87	if (ret < 0) {	87	if (ret < 0) {
88	pr_err("register_kretprobe failed, returned %d\n", ret);	88	pr_err("register_kretprobe failed, returned %d\n", ret);
89	return -1;	89	return ret;
90	}	90	}
91	pr_info("Planted return probe at %s: %p\n",	91	pr_info("Planted return probe at %s: %p\n",
92	my_kretprobe.kp.symbol_name, my_kretprobe.kp.addr);	92	my_kretprobe.kp.symbol_name, my_kretprobe.kp.addr);