diff options
| -rw-r--r-- | include/uapi/linux/netfilter/nf_conntrack_common.h | 4 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_netlink.c | 26 |
2 files changed, 29 insertions, 1 deletions
diff --git a/include/uapi/linux/netfilter/nf_conntrack_common.h b/include/uapi/linux/netfilter/nf_conntrack_common.h index 6d074d14ee27..6a8e33dd4ecb 100644 --- a/include/uapi/linux/netfilter/nf_conntrack_common.h +++ b/include/uapi/linux/netfilter/nf_conntrack_common.h @@ -82,6 +82,10 @@ enum ip_conntrack_status { IPS_DYING_BIT = 9, IPS_DYING = (1 << IPS_DYING_BIT), + /* Bits that cannot be altered from userland. */ + IPS_UNCHANGEABLE_MASK = (IPS_NAT_DONE_MASK | IPS_NAT_MASK | + IPS_EXPECTED | IPS_CONFIRMED | IPS_DYING), + /* Connection has fixed timeout. */ IPS_FIXED_TIMEOUT_BIT = 10, IPS_FIXED_TIMEOUT = (1 << IPS_FIXED_TIMEOUT_BIT), diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 27540455dc62..bf04b7e9d6f7 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -2270,6 +2270,30 @@ nla_put_failure: } static int +ctnetlink_update_status(struct nf_conn *ct, const struct nlattr * const cda[]) +{ + unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS])); + unsigned long d = ct->status ^ status; + + if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY)) + /* SEEN_REPLY bit can only be set */ + return -EBUSY; + + if (d & IPS_ASSURED && !(status & IPS_ASSURED)) + /* ASSURED bit can only be set */ + return -EBUSY; + + /* This check is less strict than ctnetlink_change_status() + * because callers often flip IPS_EXPECTED bits when sending + * an NFQA_CT attribute to the kernel. So ignore the + * unchangeable bits but do not error out. + */ + ct->status = (status & ~IPS_UNCHANGEABLE_MASK) | + (ct->status & IPS_UNCHANGEABLE_MASK); + return 0; +} + +static int ctnetlink_glue_parse_ct(const struct nlattr *cda[], struct nf_conn *ct) { int err; @@ -2280,7 +2304,7 @@ ctnetlink_glue_parse_ct(const struct nlattr *cda[], struct nf_conn *ct) return err; } if (cda[CTA_STATUS]) { - err = ctnetlink_change_status(ct, cda); + err = ctnetlink_update_status(ct, cda); if (err < 0) return err; } |