diff --git a/include/linux/netfilter/xt_qtaguid.h b/include/linux/netfilter/xt_qtaguid.h index ca60fbdec2f3..1c671552ec37 100644 --- a/include/linux/netfilter/xt_qtaguid.h +++ b/include/linux/netfilter/xt_qtaguid.h @@ -10,4 +10,5 @@ #define XT_QTAGUID_SOCKET XT_OWNER_SOCKET #define xt_qtaguid_match_info xt_owner_match_info +int qtaguid_untag(struct socket *sock, bool kernel); #endif /* _XT_QTAGUID_MATCH_H */ diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 1ae10ab2c547..f1269915090a 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -89,6 +89,7 @@ #include #include #include +#include #include @@ -451,6 +452,9 @@ int inet_release(struct socket *sock) if (sk) { long timeout; +#ifdef CONFIG_NETFILTER_XT_MATCH_QTAGUID + qtaguid_untag(sock, true); +#endif sock_rps_reset_flow(sk); /* Applications forget to leave groups before exiting */ diff --git a/net/netfilter/xt_qtaguid.c b/net/netfilter/xt_qtaguid.c index 7200e315dfb6..cdf5bfe42567 100644 --- a/net/netfilter/xt_qtaguid.c +++ b/net/netfilter/xt_qtaguid.c @@ -320,7 +320,7 @@ static void sock_tag_tree_erase(struct rb_root *st_to_free_tree) st_entry->tag, get_uid_from_tag(st_entry->tag)); rb_erase(&st_entry->sock_node, st_to_free_tree); - sockfd_put(st_entry->socket); + sock_put(st_entry->sk); kfree(st_entry); } } @@ -1910,12 +1910,12 @@ static int qtaguid_ctrl_proc_show(struct seq_file *m, void *v) { struct sock_tag *sock_tag_entry = v; uid_t uid; - long f_count; CT_DEBUG("qtaguid: proc ctrl pid=%u tgid=%u uid=%u\n", current->pid, current->tgid, current_fsuid()); if (sock_tag_entry != SEQ_START_TOKEN) { + int sk_ref_count; uid = get_uid_from_tag(sock_tag_entry->tag); CT_DEBUG("qtaguid: proc_read(): sk=%p tag=0x%llx (uid=%u) " "pid=%u\n", @@ -1924,13 +1924,13 @@ static int qtaguid_ctrl_proc_show(struct seq_file *m, void *v) uid, sock_tag_entry->pid ); - f_count = atomic_long_read( - &sock_tag_entry->socket->file->f_count); + sk_ref_count = atomic_read( + &sock_tag_entry->sk->sk_refcnt); seq_printf(m, "sock=%pK tag=0x%llx (uid=%u) pid=%u " - "f_count=%lu\n", + "f_count=%d\n", sock_tag_entry->sk, sock_tag_entry->tag, uid, - sock_tag_entry->pid, f_count); + sock_tag_entry->pid, sk_ref_count); } else { seq_printf(m, "events: sockets_tagged=%llu " "sockets_untagged=%llu " @@ -2220,8 +2220,8 @@ static int ctrl_cmd_tag(const char *input) current_fsuid()); goto err; } - CT_DEBUG("qtaguid: ctrl_tag(%s): socket->...->f_count=%ld ->sk=%p\n", - input, atomic_long_read(&el_socket->file->f_count), + CT_DEBUG("qtaguid: ctrl_tag(%s): socket->...->sk_refcnt=%d ->sk=%p\n", + input, atomic_read(&el_socket->sk->sk_refcnt), el_socket->sk); if (argc < 3) { acct_tag = make_atag_from_value(0); @@ -2264,16 +2264,9 @@ static int ctrl_cmd_tag(const char *input) struct tag_ref *prev_tag_ref_entry; CT_DEBUG("qtaguid: ctrl_tag(%s): retag for sk=%p " - "st@%p ...->f_count=%ld\n", + "st@%p ...->sk_refcnt=%d\n", input, el_socket->sk, sock_tag_entry, - atomic_long_read(&el_socket->file->f_count)); - /* - * This is a re-tagging, so release the sock_fd that was - * locked at the time of the 1st tagging. - * There is still the ref from this call's sockfd_lookup() so - * it can be done within the spinlock. - */ - sockfd_put(sock_tag_entry->socket); + atomic_read(&el_socket->sk->sk_refcnt)); prev_tag_ref_entry = lookup_tag_ref(sock_tag_entry->tag, &uid_tag_data_entry); BUG_ON(IS_ERR_OR_NULL(prev_tag_ref_entry)); @@ -2298,8 +2291,12 @@ static int ctrl_cmd_tag(const char *input) res = -ENOMEM; goto err_put; } + /* + * Hold the sk refcount here to make sure the sk pointer cannot + * be freed and reused + */ + sock_hold(el_socket->sk); sock_tag_entry->sk = el_socket->sk; - sock_tag_entry->socket = el_socket; sock_tag_entry->pid = current->tgid; sock_tag_entry->tag = combine_atag_with_uid(acct_tag, uid); @@ -2326,15 +2323,16 @@ static int ctrl_cmd_tag(const char *input) } spin_unlock_bh(&uid_tag_data_tree_lock); spin_unlock_bh(&sock_tag_list_lock); - /* We keep the ref to the socket (file) until it is untagged */ - CT_DEBUG("qtaguid: ctrl_tag(%s): done st@%p ...->f_count=%ld\n", + /* We keep the ref to the sk until it is untagged */ + CT_DEBUG("qtaguid: ctrl_tag(%s): done st@%p ...->sk_refcnt=%d\n", input, sock_tag_entry, - atomic_long_read(&el_socket->file->f_count)); + atomic_read(&el_socket->sk->sk_refcnt)); + sockfd_put(el_socket); return 0; err_put: - CT_DEBUG("qtaguid: ctrl_tag(%s): done. ...->f_count=%ld\n", - input, atomic_long_read(&el_socket->file->f_count) - 1); + CT_DEBUG("qtaguid: ctrl_tag(%s): done. ...->sk_refcnt=%d\n", + input, atomic_read(&el_socket->sk->sk_refcnt) - 1); /* Release the sock_fd that was grabbed by sockfd_lookup(). */ sockfd_put(el_socket); return res; @@ -2350,17 +2348,13 @@ static int ctrl_cmd_untag(const char *input) int sock_fd = 0; struct socket *el_socket; int res, argc; - struct sock_tag *sock_tag_entry; - struct tag_ref *tag_ref_entry; - struct uid_tag_data *utd_entry; - struct proc_qtu_data *pqd_entry; argc = sscanf(input, "%c %d", &cmd, &sock_fd); CT_DEBUG("qtaguid: ctrl_untag(%s): argc=%d cmd=%c sock_fd=%d\n", input, argc, cmd, sock_fd); if (argc < 2) { res = -EINVAL; - goto err; + return res; } el_socket = sockfd_lookup(sock_fd, &res); /* This locks the file */ if (!el_socket) { @@ -2368,17 +2362,31 @@ static int ctrl_cmd_untag(const char *input) " sock_fd=%d err=%d pid=%u tgid=%u uid=%u\n", input, sock_fd, res, current->pid, current->tgid, current_fsuid()); - goto err; + return res; } CT_DEBUG("qtaguid: ctrl_untag(%s): socket->...->f_count=%ld ->sk=%p\n", input, atomic_long_read(&el_socket->file->f_count), el_socket->sk); + res = qtaguid_untag(el_socket, false); + sockfd_put(el_socket); + return res; +} + +int qtaguid_untag(struct socket *el_socket, bool kernel) +{ + int res; + pid_t pid; + struct sock_tag *sock_tag_entry; + struct tag_ref *tag_ref_entry; + struct uid_tag_data *utd_entry; + struct proc_qtu_data *pqd_entry; + spin_lock_bh(&sock_tag_list_lock); sock_tag_entry = get_sock_stat_nl(el_socket->sk); if (!sock_tag_entry) { spin_unlock_bh(&sock_tag_list_lock); res = -EINVAL; - goto err_put; + return res; } /* * The socket already belongs to the current process @@ -2390,20 +2398,26 @@ static int ctrl_cmd_untag(const char *input) BUG_ON(!tag_ref_entry); BUG_ON(tag_ref_entry->num_sock_tags <= 0); spin_lock_bh(&uid_tag_data_tree_lock); + if (kernel) + pid = sock_tag_entry->pid; + else + pid = current->tgid; pqd_entry = proc_qtu_data_tree_search( - &proc_qtu_data_tree, current->tgid); + &proc_qtu_data_tree, pid); /* * TODO: remove if, and start failing. * At first, we want to catch user-space code that is not * opening the /dev/xt_qtaguid. */ - if (IS_ERR_OR_NULL(pqd_entry)) + if (IS_ERR_OR_NULL(pqd_entry) || !sock_tag_entry->list.next) { pr_warn_once("qtaguid: %s(): " "User space forgot to open /dev/xt_qtaguid? " - "pid=%u tgid=%u uid=%u\n", __func__, - current->pid, current->tgid, current_fsuid()); - else + "pid=%u tgid=%u sk_pid=%u, uid=%u\n", __func__, + current->pid, current->tgid, sock_tag_entry->pid, + from_kuid(&init_user_ns, current_fsuid())); + } else { list_del(&sock_tag_entry->list); + } spin_unlock_bh(&uid_tag_data_tree_lock); /* * We don't free tag_ref from the utd_entry here, @@ -2412,30 +2426,17 @@ static int ctrl_cmd_untag(const char *input) tag_ref_entry->num_sock_tags--; spin_unlock_bh(&sock_tag_list_lock); /* - * Release the sock_fd that was grabbed at tag time, - * and once more for the sockfd_lookup() here. + * Release the sock_fd that was grabbed at tag time. */ - sockfd_put(sock_tag_entry->socket); - CT_DEBUG("qtaguid: ctrl_untag(%s): done. st@%p ...->f_count=%ld\n", - input, sock_tag_entry, - atomic_long_read(&el_socket->file->f_count) - 1); - sockfd_put(el_socket); + sock_put(sock_tag_entry->sk); + CT_DEBUG("qtaguid: done. st@%p ...->sk_refcnt=%d\n", + sock_tag_entry, + atomic_read(&el_socket->sk->sk_refcnt)); kfree(sock_tag_entry); atomic64_inc(&qtu_events.sockets_untagged); return 0; - -err_put: - CT_DEBUG("qtaguid: ctrl_untag(%s): done. socket->...->f_count=%ld\n", - input, atomic_long_read(&el_socket->file->f_count) - 1); - /* Release the sock_fd that was grabbed by sockfd_lookup(). */ - sockfd_put(el_socket); - return res; - -err: - CT_DEBUG("qtaguid: ctrl_untag(%s): done.\n", input); - return res; } static int qtaguid_ctrl_parse(const char *input, int count) diff --git a/net/netfilter/xt_qtaguid_internal.h b/net/netfilter/xt_qtaguid_internal.h index 6dc14a9c6889..8178fbdfb036 100644 --- a/net/netfilter/xt_qtaguid_internal.h +++ b/net/netfilter/xt_qtaguid_internal.h @@ -256,8 +256,6 @@ struct iface_stat_work { struct sock_tag { struct rb_node sock_node; struct sock *sk; /* Only used as a number, never dereferenced */ - /* The socket is needed for sockfd_put() */ - struct socket *socket; /* Used to associate with a given pid */ struct list_head list; /* in proc_qtu_data.sock_tag_list */ pid_t pid; diff --git a/net/netfilter/xt_qtaguid_print.c b/net/netfilter/xt_qtaguid_print.c index f6a00a3520ed..2a7190d285e6 100644 --- a/net/netfilter/xt_qtaguid_print.c +++ b/net/netfilter/xt_qtaguid_print.c @@ -24,7 +24,7 @@ #include #include #include - +#include #include "xt_qtaguid_internal.h" #include "xt_qtaguid_print.h" @@ -237,10 +237,10 @@ char *pp_sock_tag(struct sock_tag *st) tag_str = pp_tag_t(&st->tag); res = kasprintf(GFP_ATOMIC, "sock_tag@%p{" "sock_node=rb_node{...}, " - "sk=%p socket=%p (f_count=%lu), list=list_head{...}, " + "sk=%p (f_count=%d), list=list_head{...}, " "pid=%u, tag=%s}", - st, st->sk, st->socket, atomic_long_read( - &st->socket->file->f_count), + st, st->sk, atomic_read( + &st->sk->sk_refcnt), st->pid, tag_str); _bug_on_err_or_null(res); kfree(tag_str);