diff --git a/fs/namespace.c b/fs/namespace.c index 58659bf9d0d73..733d5e8791136 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2287,6 +2287,19 @@ static int graft_tree(struct mount *mnt, struct mount *p, struct mountpoint *mp) return attach_recursive_mnt(mnt, p, mp, false); } +static int may_change_propagation(const struct mount *m) +{ + struct mnt_namespace *ns = m->mnt_ns; + + // it must be mounted in some namespace + if (IS_ERR_OR_NULL(ns)) // is_mounted() + return -EINVAL; + // and the caller must be admin in userns of that namespace + if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN)) + return -EPERM; + return 0; +} + /* * Sanity check the flags to change_mnt_propagation. */ @@ -2323,6 +2336,10 @@ static int do_change_type(struct path *path, int ms_flags) return -EINVAL; namespace_lock(); + err = may_change_propagation(mnt); + if (err) + goto out_unlock; + if (type == MS_SHARED) { err = invent_group_ids(mnt, recurse); if (err) @@ -2695,6 +2712,71 @@ static bool check_for_nsfs_mounts(struct mount *subtree) return ret; } +static int do_set_group(struct path *from_path, struct path *to_path) +{ + struct mount *from, *to; + int err; + + from = real_mount(from_path->mnt); + to = real_mount(to_path->mnt); + + namespace_lock(); + + err = may_change_propagation(from); + if (err) + goto out; + err = may_change_propagation(to); + if (err) + goto out; + + err = -EINVAL; + /* To and From paths should be mount roots */ + if (from_path->dentry != from_path->mnt->mnt_root) + goto out; + if (to_path->dentry != to_path->mnt->mnt_root) + goto out; + + /* Setting sharing groups is only allowed across same superblock */ + if (from->mnt.mnt_sb != to->mnt.mnt_sb) + goto out; + + /* From mount root should be wider than To mount root */ + if (!is_subdir(to->mnt.mnt_root, from->mnt.mnt_root)) + goto out; + + /* From mount should not have locked children in place of To's root */ + if (has_locked_children(from, to->mnt.mnt_root)) + goto out; + + /* Setting sharing groups is only allowed on private mounts */ + if (IS_MNT_SHARED(to) || IS_MNT_SLAVE(to)) + goto out; + + /* From should not be private */ + if (!IS_MNT_SHARED(from) && !IS_MNT_SLAVE(from)) + goto out; + + if (IS_MNT_SLAVE(from)) { + struct mount *m = from->mnt_master; + + list_add(&to->mnt_slave, &from->mnt_slave); + to->mnt_master = m; + } + + if (IS_MNT_SHARED(from)) { + to->mnt_group_id = from->mnt_group_id; + list_add(&to->mnt_share, &from->mnt_share); + lock_mount_hash(); + set_mnt_shared(to); + unlock_mount_hash(); + } + + err = 0; +out: + namespace_unlock(); + return err; +} + static int do_move_mount(struct path *old_path, struct path *new_path) { struct mnt_namespace *ns; @@ -3679,7 +3761,10 @@ SYSCALL_DEFINE5(move_mount, if (ret < 0) goto out_to; - ret = do_move_mount(&from_path, &to_path); + if (flags & MOVE_MOUNT_SET_GROUP) + ret = do_set_group(&from_path, &to_path); + else + ret = do_move_mount(&from_path, &to_path); out_to: path_put(&to_path); diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h index 1419391199f79..016cc7f41c54d 100644 --- a/include/net/netfilter/nf_conntrack.h +++ b/include/net/netfilter/nf_conntrack.h @@ -300,8 +300,19 @@ static inline bool nf_ct_is_expired(const struct nf_conn *ct) /* use after obtaining a reference count */ static inline bool nf_ct_should_gc(const struct nf_conn *ct) { - return nf_ct_is_expired(ct) && nf_ct_is_confirmed(ct) && - !nf_ct_is_dying(ct); + if (!nf_ct_is_confirmed(ct)) + return false; + + /* load ct->timeout after is_confirmed() test. + * Pairs with __nf_conntrack_confirm() which: + * 1. Increases ct->timeout value + * 2. Inserts ct into rcu hlist + * 3. Sets the confirmed bit + * 4. Unlocks the hlist lock + */ + smp_acquire__after_ctrl_dep(); + + return nf_ct_is_expired(ct) && !nf_ct_is_dying(ct); } #define NF_CT_DAY (86400 * HZ) diff --git a/include/uapi/linux/mount.h b/include/uapi/linux/mount.h index dd7a166fdf9c2..4d93967f8aea0 100644 --- a/include/uapi/linux/mount.h +++ b/include/uapi/linux/mount.h @@ -73,7 +73,8 @@ #define MOVE_MOUNT_T_SYMLINKS 0x00000010 /* Follow symlinks on to path */ #define MOVE_MOUNT_T_AUTOMOUNTS 0x00000020 /* Follow automounts on to path */ #define MOVE_MOUNT_T_EMPTY_PATH 0x00000040 /* Empty to path permitted */ -#define MOVE_MOUNT__MASK 0x00000077 +#define MOVE_MOUNT_SET_GROUP 0x00000100 /* Set sharing group instead */ +#define MOVE_MOUNT__MASK 0x00000177 /* * fsopen() flags. diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index ce4e6db8d923d..f547134c3055c 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -803,8 +803,8 @@ static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im) } else { im->mca_crcount = idev->mc_qrv; } - in6_dev_put(pmc->idev); ip6_mc_clear_src(pmc); + in6_dev_put(pmc->idev); kfree_rcu(pmc, rcu); } } diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 3a194a89a3a8d..e8843c397b0b7 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1083,6 +1083,12 @@ static int nf_ct_resolve_clash_harder(struct sk_buff *skb, u32 repl_idx) hlist_nulls_add_head_rcu(&loser_ct->tuplehash[IP_CT_DIR_REPLY].hnnode, &nf_conntrack_hash[repl_idx]); + /* confirmed bit must be set after hlist add, not before: + * loser_ct can still be visible to other cpu due to + * SLAB_TYPESAFE_BY_RCU. + */ + smp_mb__before_atomic(); + set_bit(IPS_CONFIRMED_BIT, &loser_ct->status); NF_CT_STAT_INC(net, clash_resolve); return NF_ACCEPT; @@ -1220,8 +1226,6 @@ __nf_conntrack_confirm(struct sk_buff *skb) * user context, else we insert an already 'dead' hash, blocking * further use of that particular connection -JM. */ - ct->status |= IPS_CONFIRMED; - if (unlikely(nf_ct_is_dying(ct))) { NF_CT_STAT_INC(net, insert_failed); goto dying; @@ -1253,7 +1257,7 @@ __nf_conntrack_confirm(struct sk_buff *skb) } } - /* Timer relative to confirmation time, not original + /* Timeout is relative to confirmation time, not original setting time, otherwise we'd get timer wrap in weird delay cases. */ ct->timeout += nfct_time_stamp; @@ -1261,11 +1265,21 @@ __nf_conntrack_confirm(struct sk_buff *skb) __nf_conntrack_insert_prepare(ct); /* Since the lookup is lockless, hash insertion must be done after - * starting the timer and setting the CONFIRMED bit. The RCU barriers - * guarantee that no other CPU can find the conntrack before the above - * stores are visible. + * setting ct->timeout. The RCU barriers guarantee that no other CPU + * can find the conntrack before the above stores are visible. */ __nf_conntrack_hash_insert(ct, hash, reply_hash); + + /* IPS_CONFIRMED unset means 'ct not (yet) in hash', conntrack lookups + * skip entries that lack this bit. This happens when a CPU is looking + * at a stale entry that is being recycled due to SLAB_TYPESAFE_BY_RCU + * or when another CPU encounters this entry right after the insertion + * but before the set-confirm-bit below. This bit must not be set until + * after __nf_conntrack_hash_insert(). + */ + smp_mb__before_atomic(); + set_bit(IPS_CONFIRMED_BIT, &ct->status); + nf_conntrack_double_unlock(hash, reply_hash); local_bh_enable(); diff --git a/net/sctp/input.c b/net/sctp/input.c index 4f43afa8678f9..a5f5ea982e4e4 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -114,7 +114,7 @@ int sctp_rcv(struct sk_buff *skb) * it's better to just linearize it otherwise crc computing * takes longer. */ - if ((!is_gso && skb_linearize(skb)) || + if (((!is_gso || skb_cloned(skb)) && skb_linearize(skb)) || !pskb_may_pull(skb, sizeof(struct sctphdr))) goto discard_it; diff --git a/net/tipc/topsrv.c b/net/tipc/topsrv.c index e3b427a703980..4292c0f1e3daa 100644 --- a/net/tipc/topsrv.c +++ b/net/tipc/topsrv.c @@ -699,8 +699,10 @@ static void tipc_topsrv_stop(struct net *net) for (id = 0; srv->idr_in_use; id++) { con = idr_find(&srv->conn_idr, id); if (con) { + conn_get(con); spin_unlock_bh(&srv->idr_lock); tipc_conn_close(con); + conn_put(con); spin_lock_bh(&srv->idr_lock); } } diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c index 801dd8d44953b..6813fd3a5fc59 100644 --- a/sound/pci/hda/patch_ca0132.c +++ b/sound/pci/hda/patch_ca0132.c @@ -4399,7 +4399,7 @@ static int add_tuning_control(struct hda_codec *codec, } knew.private_value = HDA_COMPOSE_AMP_VAL(nid, 1, 0, type); - sprintf(namestr, "%s %s Volume", name, dirstr[dir]); + snprintf(namestr, sizeof(namestr), "%s %s Volume", name, dirstr[dir]); return snd_hda_ctl_add(codec, nid, snd_ctl_new1(&knew, codec)); }