Revert "kretprobe: check re-registration of the same kretprobe earlier"

hulk inclusion
category: bugfix
bugzilla: 31369
CVE: NA

-----------------------------------------------

This reverts commit bd1ed1b7.
Following patches mainline has fixed this issue:
0188b878 ("kretprobe: Avoid re-registration of the same kretprobe earlier")
33b1d146 ("kprobes: Warn if the kprobe is reregistered")
Signed-off-by: NWang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: NCheng Jian <cj.chengjian@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

kernel/kprobes.c

@@ -1957,14 +1957,6 @@ int register_kretprobe(struct kretprobe *rp)
 		}
 	}
 
-	/*
-	 * Return error if it's being re-registered,
-	 * also give a warning message to the developer.
-	 */
-	ret = check_kprobe_rereg(&rp->kp);
-	if (WARN_ON(ret))
-		return ret;
-
 	rp->kp.pre_handler = pre_handler_kretprobe;
 	rp->kp.post_handler = NULL;
 	rp->kp.fault_handler = NULL;