From 976d302fb6165ad620778d7ba834cde6e3fe9f9f Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 18 Nov 2022 10:46:07 -0800 Subject: [PATCH 1/2] mptcp: deduplicate error paths on endpoint creation When endpoint creation fails, we need to free the newly allocated entry and eventually destroy the paired mptcp listener socket. Consolidate such action in a single point let all the errors path reach it. Reviewed-by: Mat Martineau Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/pm_netlink.c | 35 +++++++++++++---------------------- 1 file changed, 13 insertions(+), 22 deletions(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 9813ed0fde9b..fdf2ee29f762 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -1003,16 +1003,12 @@ static int mptcp_pm_nl_create_listen_socket(struct sock *sk, return err; msk = mptcp_sk(entry->lsk->sk); - if (!msk) { - err = -EINVAL; - goto out; - } + if (!msk) + return -EINVAL; ssock = __mptcp_nmpc_socket(msk); - if (!ssock) { - err = -EINVAL; - goto out; - } + if (!ssock) + return -EINVAL; mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); #if IS_ENABLED(CONFIG_MPTCP_IPV6) @@ -1022,20 +1018,16 @@ static int mptcp_pm_nl_create_listen_socket(struct sock *sk, err = kernel_bind(ssock, (struct sockaddr *)&addr, addrlen); if (err) { pr_warn("kernel_bind error, err=%d", err); - goto out; + return err; } err = kernel_listen(ssock, backlog); if (err) { pr_warn("kernel_listen error, err=%d", err); - goto out; + return err; } return 0; - -out: - sock_release(entry->lsk); - return err; } int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc) @@ -1327,7 +1319,7 @@ static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info) return -EINVAL; } - entry = kmalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT); + entry = kzalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT); if (!entry) { GENL_SET_ERR_MSG(info, "can't allocate addr"); return -ENOMEM; @@ -1338,22 +1330,21 @@ static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info) ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); if (ret) { GENL_SET_ERR_MSG(info, "create listen socket error"); - kfree(entry); - return ret; + goto out_free; } } ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); if (ret < 0) { GENL_SET_ERR_MSG(info, "too many addresses or duplicate one"); - if (entry->lsk) - sock_release(entry->lsk); - kfree(entry); - return ret; + goto out_free; } mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); - return 0; + +out_free: + __mptcp_pm_release_addr_entry(entry); + return ret; } int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, From a3400e8746b626531099e4d9fd8eac41be066683 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 18 Nov 2022 10:46:08 -0800 Subject: [PATCH 2/2] mptcp: more detailed error reporting on endpoint creation Endpoint creation can fail for a number of reasons; in case of failure append the error number to the extended ack message, using a newly introduced generic helper. Additionally let mptcp_pm_nl_append_new_local_addr() report different error reasons. Reviewed-by: Mat Martineau Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- include/net/genetlink.h | 3 +++ net/mptcp/pm_netlink.c | 24 +++++++++++++----------- 2 files changed, 16 insertions(+), 11 deletions(-) diff --git a/include/net/genetlink.h b/include/net/genetlink.h index d21210709f84..ed4622dd4828 100644 --- a/include/net/genetlink.h +++ b/include/net/genetlink.h @@ -125,6 +125,9 @@ static inline void genl_info_net_set(struct genl_info *info, struct net *net) #define GENL_SET_ERR_MSG(info, msg) NL_SET_ERR_MSG((info)->extack, msg) +#define GENL_SET_ERR_MSG_FMT(info, msg, args...) \ + NL_SET_ERR_MSG_FMT((info)->extack, msg, ##args) + /* Report that a root attribute is missing */ #define GENL_REQ_ATTR_CHECK(info, attr) ({ \ struct genl_info *__info = (info); \ diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index fdf2ee29f762..d66fbd558263 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -912,10 +912,14 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, */ if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) pernet->next_id = 1; - if (pernet->addrs >= MPTCP_PM_ADDR_MAX) + if (pernet->addrs >= MPTCP_PM_ADDR_MAX) { + ret = -ERANGE; goto out; - if (test_bit(entry->addr.id, pernet->id_bitmap)) + } + if (test_bit(entry->addr.id, pernet->id_bitmap)) { + ret = -EBUSY; goto out; + } /* do not insert duplicate address, differentiate on port only * singled addresses @@ -929,8 +933,10 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, * endpoint is an implicit one and the user-space * did not provide an endpoint id */ - if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)) + if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)) { + ret = -EEXIST; goto out; + } if (entry->addr.id) goto out; @@ -1016,16 +1022,12 @@ static int mptcp_pm_nl_create_listen_socket(struct sock *sk, addrlen = sizeof(struct sockaddr_in6); #endif err = kernel_bind(ssock, (struct sockaddr *)&addr, addrlen); - if (err) { - pr_warn("kernel_bind error, err=%d", err); + if (err) return err; - } err = kernel_listen(ssock, backlog); - if (err) { - pr_warn("kernel_listen error, err=%d", err); + if (err) return err; - } return 0; } @@ -1329,13 +1331,13 @@ static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info) if (entry->addr.port) { ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); if (ret) { - GENL_SET_ERR_MSG(info, "create listen socket error"); + GENL_SET_ERR_MSG_FMT(info, "create listen socket error: %d", ret); goto out_free; } } ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); if (ret < 0) { - GENL_SET_ERR_MSG(info, "too many addresses or duplicate one"); + GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret); goto out_free; }