diff --git a/include/linux/inet_diag.h b/include/linux/inet_diag.h index 1bb94cac265f..e4ba25d63913 100644 --- a/include/linux/inet_diag.h +++ b/include/linux/inet_diag.h @@ -38,9 +38,13 @@ struct inet_diag_handler { __u16 idiag_info_size; }; +struct bpf_sk_storage_diag; struct inet_diag_dump_data { struct nlattr *req_nlas[__INET_DIAG_REQ_MAX]; #define inet_diag_nla_bc req_nlas[INET_DIAG_REQ_BYTECODE] +#define inet_diag_nla_bpf_stgs req_nlas[INET_DIAG_REQ_SK_BPF_STORAGES] + + struct bpf_sk_storage_diag *bpf_stg_diag; }; struct inet_connection_sock; diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 205fa7b1f07a..788969ccbbde 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -188,10 +188,10 @@ struct netlink_callback { struct module *module; struct netlink_ext_ack *extack; u16 family; - u16 min_dump_alloc; - bool strict_check; u16 answer_flags; + u32 min_dump_alloc; unsigned int prev_seq, seq; + bool strict_check; union { u8 ctx[48]; diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h index bab9a9f8da12..75dffd78363a 100644 --- a/include/uapi/linux/inet_diag.h +++ b/include/uapi/linux/inet_diag.h @@ -64,6 +64,7 @@ struct inet_diag_req_raw { enum { INET_DIAG_REQ_NONE, INET_DIAG_REQ_BYTECODE, + INET_DIAG_REQ_SK_BPF_STORAGES, __INET_DIAG_REQ_MAX, }; @@ -155,6 +156,7 @@ enum { INET_DIAG_CLASS_ID, /* request as INET_DIAG_TCLASS */ INET_DIAG_MD5SIG, INET_DIAG_ULP_INFO, + INET_DIAG_SK_BPF_STORAGES, __INET_DIAG_MAX, }; diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index 4bce8a477699..e1cad25909df 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include @@ -156,6 +157,8 @@ errout: } EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill); +#define MAX_DUMP_ALLOC_SIZE (KMALLOC_MAX_SIZE - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) + int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *req, @@ -163,12 +166,14 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, { const struct tcp_congestion_ops *ca_ops; const struct inet_diag_handler *handler; + struct inet_diag_dump_data *cb_data; int ext = req->idiag_ext; struct inet_diag_msg *r; struct nlmsghdr *nlh; struct nlattr *attr; void *info = NULL; + cb_data = cb->data; handler = inet_diag_table[req->sdiag_protocol]; BUG_ON(!handler); @@ -302,6 +307,48 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, goto errout; } + /* Keep it at the end for potential retry with a larger skb, + * or else do best-effort fitting, which is only done for the + * first_nlmsg. + */ + if (cb_data->bpf_stg_diag) { + bool first_nlmsg = ((unsigned char *)nlh == skb->data); + unsigned int prev_min_dump_alloc; + unsigned int total_nla_size = 0; + unsigned int msg_len; + int err; + + msg_len = skb_tail_pointer(skb) - (unsigned char *)nlh; + err = bpf_sk_storage_diag_put(cb_data->bpf_stg_diag, sk, skb, + INET_DIAG_SK_BPF_STORAGES, + &total_nla_size); + + if (!err) + goto out; + + total_nla_size += msg_len; + prev_min_dump_alloc = cb->min_dump_alloc; + if (total_nla_size > prev_min_dump_alloc) + cb->min_dump_alloc = min_t(u32, total_nla_size, + MAX_DUMP_ALLOC_SIZE); + + if (!first_nlmsg) + goto errout; + + if (cb->min_dump_alloc > prev_min_dump_alloc) + /* Retry with pskb_expand_head() with + * __GFP_DIRECT_RECLAIM + */ + goto errout; + + WARN_ON_ONCE(total_nla_size <= prev_min_dump_alloc); + + /* Send what we have for this sk + * and move on to the next sk in the following + * dump() + */ + } + out: nlmsg_end(skb, nlh); return 0; @@ -1022,8 +1069,11 @@ static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *r) { const struct inet_diag_handler *handler; + u32 prev_min_dump_alloc; int err = 0; +again: + prev_min_dump_alloc = cb->min_dump_alloc; handler = inet_diag_lock_handler(r->sdiag_protocol); if (!IS_ERR(handler)) handler->dump(skb, cb, r); @@ -1031,6 +1081,15 @@ static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, err = PTR_ERR(handler); inet_diag_unlock_handler(handler); + /* The skb is not large enough to fit one sk info and + * inet_sk_diag_fill() has requested for a larger skb. + */ + if (!skb->len && cb->min_dump_alloc > prev_min_dump_alloc) { + err = pskb_expand_head(skb, 0, cb->min_dump_alloc, GFP_KERNEL); + if (!err) + goto again; + } + return err ? : skb->len; } @@ -1068,6 +1127,18 @@ static int __inet_diag_dump_start(struct netlink_callback *cb, int hdrlen) } } + nla = cb_data->inet_diag_nla_bpf_stgs; + if (nla) { + struct bpf_sk_storage_diag *bpf_stg_diag; + + bpf_stg_diag = bpf_sk_storage_diag_alloc(nla); + if (IS_ERR(bpf_stg_diag)) { + kfree(cb_data); + return PTR_ERR(bpf_stg_diag); + } + cb_data->bpf_stg_diag = bpf_stg_diag; + } + cb->data = cb_data; return 0; } @@ -1084,6 +1155,9 @@ static int inet_diag_dump_start_compat(struct netlink_callback *cb) static int inet_diag_dump_done(struct netlink_callback *cb) { + struct inet_diag_dump_data *cb_data = cb->data; + + bpf_sk_storage_diag_free(cb_data->bpf_stg_diag); kfree(cb->data); return 0;