6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx> [ Upstream commit f448451aa62d54be16acb0034223c17e0d12bc69 ] This helper is confusing. It is in pm.c, but it is specific to the in-kernel PM and it cannot be used by the userspace one. Also, it simply calls one in-kernel specific function with the PM lock, while the similar mptcp_pm_remove_addr() helper requires the PM lock. What's left is the pr_debug(), which is not that useful, because a similar one is present in the only function called by this helper: mptcp_pm_nl_rm_subflow_received() After these modifications, this helper can be marked as 'static', and the lock can be taken only once in mptcp_pm_flush_addrs_and_subflows(). Note that it is not a bug fix, but it will help backporting the following commits. Fixes: 0ee4261a3681 ("mptcp: implement mptcp_pm_remove_subflow") Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Mat Martineau <martineau@xxxxxxxxxx> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx> Link: https://patch.msgid.link/20240819-net-mptcp-pm-reusing-id-v1-7-38035d40de5b@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/mptcp/pm.c | 10 ---------- net/mptcp/pm_netlink.c | 16 +++++++--------- net/mptcp/protocol.h | 3 --- 3 files changed, 7 insertions(+), 22 deletions(-) diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index 5d9baade5c3b4..5646c7275a92d 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -59,16 +59,6 @@ int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_ return 0; } -int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list) -{ - pr_debug("msk=%p, rm_list_nr=%d", msk, rm_list->nr); - - spin_lock_bh(&msk->pm.lock); - mptcp_pm_nl_rm_subflow_received(msk, rm_list); - spin_unlock_bh(&msk->pm.lock); - return 0; -} - /* path manager event handlers */ void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 6a85e9665080c..3b3e656a2ab09 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -883,8 +883,8 @@ static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); } -void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, - const struct mptcp_rm_list *rm_list) +static void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, + const struct mptcp_rm_list *rm_list) { mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); } @@ -1526,7 +1526,9 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); if (remove_subflow) { - mptcp_pm_remove_subflow(msk, &list); + spin_lock_bh(&msk->pm.lock); + mptcp_pm_nl_rm_subflow_received(msk, &list); + spin_unlock_bh(&msk->pm.lock); } else if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { /* If the subflow has been used, but now closed */ spin_lock_bh(&msk->pm.lock); @@ -1674,18 +1676,14 @@ void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, alist.ids[alist.nr++] = entry->addr.id; } + spin_lock_bh(&msk->pm.lock); if (alist.nr) { - spin_lock_bh(&msk->pm.lock); msk->pm.add_addr_signaled -= alist.nr; mptcp_pm_remove_addr(msk, &alist); - spin_unlock_bh(&msk->pm.lock); } - if (slist.nr) - mptcp_pm_remove_subflow(msk, &slist); - + mptcp_pm_nl_rm_subflow_received(msk, &slist); /* Reset counters: maybe some subflows have been removed before */ - spin_lock_bh(&msk->pm.lock); bitmap_fill(msk->pm.id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); msk->pm.local_addr_used = 0; spin_unlock_bh(&msk->pm.lock); diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index b4d6710e6ca3a..c3cd68edab779 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -836,7 +836,6 @@ int mptcp_pm_announce_addr(struct mptcp_sock *msk, const struct mptcp_addr_info *addr, bool echo); int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); -int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, struct list_head *rm_list); @@ -931,8 +930,6 @@ static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflo void __init mptcp_pm_nl_init(void); void mptcp_pm_nl_work(struct mptcp_sock *msk); -void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, - const struct mptcp_rm_list *rm_list); unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); -- 2.43.0