| Message ID | 9db6df3e544dd6ec6e4ec5091b0a750ac08d6e1b.1616125961.git.lucien.xin@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 8ff0b1f08ea73e5c08f5addd23481e76a60e741c |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | sctp: move sk_route_caps check and set into sctp_outq_flush_transports | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Guessed tree name to be net-next |
| netdev/subject_prefix | warning | Target tree name not specified in the subject |
| netdev/cc_maintainers | warning | 2 maintainers not CCed: vyasevich@gmail.com nhorman@tuxdriver.com |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 32 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
Hello: This patch was applied to netdev/net.git (refs/heads/master): On Fri, 19 Mar 2021 11:52:41 +0800 you wrote: > The sk's sk_route_caps is set in sctp_packet_config, and later it > only needs to change when traversing the transport_list in a loop, > as the dst might be changed in the tx path. > > So move sk_route_caps check and set into sctp_outq_flush_transports > from sctp_packet_transmit. This also fixes a dst leak reported by > Chen Yi: > > [...] Here is the summary with links: - sctp: move sk_route_caps check and set into sctp_outq_flush_transports https://git.kernel.org/netdev/net/c/8ff0b1f08ea7 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/net/sctp/output.c b/net/sctp/output.c index 6614c9f..a6aa17d 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -584,13 +584,6 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp) goto out; } - rcu_read_lock(); - if (__sk_dst_get(sk) != tp->dst) { - dst_hold(tp->dst); - sk_setup_caps(sk, tp->dst); - } - rcu_read_unlock(); - /* pack up chunks */ pkt_count = sctp_packet_pack(packet, head, gso, gfp); if (!pkt_count) { diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c index 3fd06a2..5cb1aa5 100644 --- a/net/sctp/outqueue.c +++ b/net/sctp/outqueue.c @@ -1135,6 +1135,7 @@ static void sctp_outq_flush_data(struct sctp_flush_ctx *ctx, static void sctp_outq_flush_transports(struct sctp_flush_ctx *ctx) { + struct sock *sk = ctx->asoc->base.sk; struct list_head *ltransport; struct sctp_packet *packet; struct sctp_transport *t; @@ -1144,6 +1145,12 @@ static void sctp_outq_flush_transports(struct sctp_flush_ctx *ctx) t = list_entry(ltransport, struct sctp_transport, send_ready); packet = &t->packet; if (!sctp_packet_empty(packet)) { + rcu_read_lock(); + if (t->dst && __sk_dst_get(sk) != t->dst) { + dst_hold(t->dst); + sk_setup_caps(sk, t->dst); + } + rcu_read_unlock(); error = sctp_packet_transmit(packet, ctx->gfp); if (error < 0) ctx->q->asoc->base.sk->sk_err = -error;
The sk's sk_route_caps is set in sctp_packet_config, and later it only needs to change when traversing the transport_list in a loop, as the dst might be changed in the tx path. So move sk_route_caps check and set into sctp_outq_flush_transports from sctp_packet_transmit. This also fixes a dst leak reported by Chen Yi: https://bugzilla.kernel.org/show_bug.cgi?id=212227 As calling sk_setup_caps() in sctp_packet_transmit may also set the sk_route_caps for the ctrl sock in a netns. When the netns is being deleted, the ctrl sock's releasing is later than dst dev's deleting, which will cause this dev's deleting to hang and dmesg error occurs: unregister_netdevice: waiting for xxx to become free. Usage count = 1 Reported-by: Chen Yi <yiche@redhat.com> Fixes: bcd623d8e9fa ("sctp: call sk_setup_caps in sctp_packet_transmit instead") Signed-off-by: Xin Long <lucien.xin@gmail.com> --- net/sctp/output.c | 7 ------- net/sctp/outqueue.c | 7 +++++++ 2 files changed, 7 insertions(+), 7 deletions(-)