Unverified Commit da325ff7 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!7235 bpf: Check rcu_read_lock_trace_held() before calling bpf map helpers 

Merge Pull Request from: @ci-robot 
 
PR sync from: Guo Mengqi <guomengqi3@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/UXBS22QMF4A6Z33I3T4XFQNDT6JIIVVV/ 
 
https://gitee.com/src-openeuler/kernel/issues/I9BV4S 
 
Link:https://gitee.com/openeuler/kernel/pulls/7235

 

Reviewed-by: default avatarXu Kuohai <xukuohai@huawei.com>
Signed-off-by: default avatarJialin Zhang <zhangjialin11@huawei.com>
parents 3fd44f97 42320311

kernel/bpf/helpers.c

+6 −5
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#include <linux/pid_namespace.h>

#include <linux/proc_ns.h>

#include <linux/security.h>

#include <linux/rcupdate_trace.h>



#include "../../lib/kstrtox.h"
@@ -24,12 +25,12 @@ 
 *

 * Different map implementations will rely on rcu in map methods

 * lookup/update/delete, therefore eBPF programs must run under rcu lock

 * if program is allowed to access maps, so check rcu_read_lock_held in

 * all three functions.

 * if program is allowed to access maps, so check rcu_read_lock_held() or

 * rcu_read_lock_trace_held() in all three functions.

 */

BPF_CALL_2(bpf_map_lookup_elem, struct bpf_map *, map, void *, key)

{

	WARN_ON_ONCE(!rcu_read_lock_held());

	WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held());

	return (unsigned long) map->ops->map_lookup_elem(map, key);

}
@@ -45,7 +46,7 @@ const struct bpf_func_proto bpf_map_lookup_elem_proto = { 
BPF_CALL_4(bpf_map_update_elem, struct bpf_map *, map, void *, key,

	   void *, value, u64, flags)

{

	WARN_ON_ONCE(!rcu_read_lock_held());

	WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held());

	return map->ops->map_update_elem(map, key, value, flags);

}
@@ -62,7 +63,7 @@ const struct bpf_func_proto bpf_map_update_elem_proto = { 


BPF_CALL_2(bpf_map_delete_elem, struct bpf_map *, map, void *, key)

{

	WARN_ON_ONCE(!rcu_read_lock_held());

	WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held());

	return map->ops->map_delete_elem(map, key);

}