diff options
| author | Florian Westphal <fw@strlen.de> | 2021-03-04 13:32:11 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-03-04 14:30:13 -0800 |
| commit | 17aee05dc8822e354f5ad2d68ee39e3ba4b6acf2 (patch) | |
| tree | 10b8a937d5859c77ac3e24fb19b5498b2227422b /net | |
| parent | eaeef1ce55ec9161e0c44ff27017777b1644b421 (diff) | |
| download | lwn-17aee05dc8822e354f5ad2d68ee39e3ba4b6acf2.tar.gz lwn-17aee05dc8822e354f5ad2d68ee39e3ba4b6acf2.zip | |
mptcp: dispose initial struct socket when its subflow is closed
Christoph Paasch reported following crash:
dst_release underflow
WARNING: CPU: 0 PID: 1319 at net/core/dst.c:175 dst_release+0xc1/0xd0 net/core/dst.c:175
CPU: 0 PID: 1319 Comm: syz-executor217 Not tainted 5.11.0-rc6af8e85128b4d0d24083c5cac646e891227052e0c #70
Call Trace:
rt_cache_route+0x12e/0x140 net/ipv4/route.c:1503
rt_set_nexthop.constprop.0+0x1fc/0x590 net/ipv4/route.c:1612
__mkroute_output net/ipv4/route.c:2484 [inline]
...
The worker leaves msk->subflow alone even when it
happened to close the subflow ssk associated with it.
Fixes: 866f26f2a9c33b ("mptcp: always graft subflow socket to parent")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/157
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/mptcp/protocol.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index aa59101ffe54..a58da04bed71 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2116,6 +2116,14 @@ static struct sock *mptcp_subflow_get_retrans(const struct mptcp_sock *msk) return backup; } +static void mptcp_dispose_initial_subflow(struct mptcp_sock *msk) +{ + if (msk->subflow) { + iput(SOCK_INODE(msk->subflow)); + msk->subflow = NULL; + } +} + /* subflow sockets can be either outgoing (connect) or incoming * (accept). * @@ -2160,6 +2168,9 @@ static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk, if (ssk == msk->last_snd) msk->last_snd = NULL; + + if (msk->subflow && ssk == msk->subflow->sk) + mptcp_dispose_initial_subflow(msk); } void mptcp_close_ssk(struct sock *sk, struct sock *ssk, @@ -2529,12 +2540,6 @@ static void __mptcp_destroy_sock(struct sock *sk) might_sleep(); - /* dispose the ancillatory tcp socket, if any */ - if (msk->subflow) { - iput(SOCK_INODE(msk->subflow)); - msk->subflow = NULL; - } - /* be sure to always acquire the join list lock, to sync vs * mptcp_finish_join(). */ @@ -2559,6 +2564,7 @@ static void __mptcp_destroy_sock(struct sock *sk) sk_stream_kill_queues(sk); xfrm_sk_free_policy(sk); sk_refcnt_debug_release(sk); + mptcp_dispose_initial_subflow(msk); sock_put(sk); } |