diff options
Diffstat (limited to 'include/linux/netfilter/ipset/ip_set_comment.h')
| -rw-r--r-- | include/linux/netfilter/ipset/ip_set_comment.h | 38 |
1 files changed, 27 insertions, 11 deletions
diff --git a/include/linux/netfilter/ipset/ip_set_comment.h b/include/linux/netfilter/ipset/ip_set_comment.h index 21217ea008d7..8d0248525957 100644 --- a/include/linux/netfilter/ipset/ip_set_comment.h +++ b/include/linux/netfilter/ipset/ip_set_comment.h @@ -16,41 +16,57 @@ ip_set_comment_uget(struct nlattr *tb) return nla_data(tb); } +/* Called from uadd only, protected by the set spinlock. + * The kadt functions don't use the comment extensions in any way. + */ static inline void ip_set_init_comment(struct ip_set_comment *comment, const struct ip_set_ext *ext) { + struct ip_set_comment_rcu *c = rcu_dereference_protected(comment->c, 1); size_t len = ext->comment ? strlen(ext->comment) : 0; - if (unlikely(comment->str)) { - kfree(comment->str); - comment->str = NULL; + if (unlikely(c)) { + kfree_rcu(c, rcu); + rcu_assign_pointer(comment->c, NULL); } if (!len) return; if (unlikely(len > IPSET_MAX_COMMENT_SIZE)) len = IPSET_MAX_COMMENT_SIZE; - comment->str = kzalloc(len + 1, GFP_ATOMIC); - if (unlikely(!comment->str)) + c = kzalloc(sizeof(*c) + len + 1, GFP_ATOMIC); + if (unlikely(!c)) return; - strlcpy(comment->str, ext->comment, len + 1); + strlcpy(c->str, ext->comment, len + 1); + rcu_assign_pointer(comment->c, c); } +/* Used only when dumping a set, protected by rcu_read_lock_bh() */ static inline int ip_set_put_comment(struct sk_buff *skb, struct ip_set_comment *comment) { - if (!comment->str) + struct ip_set_comment_rcu *c = rcu_dereference_bh(comment->c); + + if (!c) return 0; - return nla_put_string(skb, IPSET_ATTR_COMMENT, comment->str); + return nla_put_string(skb, IPSET_ATTR_COMMENT, c->str); } +/* Called from uadd/udel, flush or the garbage collectors protected + * by the set spinlock. + * Called when the set is destroyed and when there can't be any user + * of the set data anymore. + */ static inline void ip_set_comment_free(struct ip_set_comment *comment) { - if (unlikely(!comment->str)) + struct ip_set_comment_rcu *c; + + c = rcu_dereference_protected(comment->c, 1); + if (unlikely(!c)) return; - kfree(comment->str); - comment->str = NULL; + kfree_rcu(c, rcu); + rcu_assign_pointer(comment->c, NULL); } #endif |