The branch stable/13 has been updated by gallatin: URL: https://cgit.FreeBSD.org/src/commit/?id=bf2a85f4e304aa6223ab007231e71b707320600e
commit bf2a85f4e304aa6223ab007231e71b707320600e Author: Andrew Gallatin <[email protected]> AuthorDate: 2022-01-27 15:28:15 +0000 Commit: Andrew Gallatin <[email protected]> CommitDate: 2022-02-10 20:39:22 +0000 Fix a memory leak when ip_output_send() returns EAGAIN due to send tag issues When ip_output_send() returns EAGAIN due to issues with send tags (route change, lagg failover, etc), it must free the mbuf. This is because ip_output_send() was written as a wrapper/replacement for a direct call to if_output(), and the contract with if_output() has historically been that it owns the mbufs once called. When ip_output_send() failed to free mbufs, it violated this assumption and lead to leaked mbufs. This was noticed when using NIC TLS in combination with hardware rate-limited connections. When seeing lots of NIC output drops triggered ratelimit send tag changes, we noticed we were leaking ktls_sessions, send tags and mbufs. This was due ip_output_send() leaking mbufs which held references to ktls_sessions, which in turn held references to send tags. Many thanks to jbh, rrs, hselasky and markj for their help in debugging this. Sponsored by: Netflix Differential Revision: https://reviews.freebsd.org/D34054 Reviewed by: hselasky, jhb, rrs MFC after: 2 weeks (cherry picked from commit 9ba117960e1755a693f9361e4d076630dfe13dba) --- sys/netinet/ip_output.c | 2 ++ sys/netinet6/ip6_output.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c index a011c28441bd..a23a38b08fa8 100644 --- a/sys/netinet/ip_output.c +++ b/sys/netinet/ip_output.c @@ -239,6 +239,7 @@ ip_output_send(struct inpcb *inp, struct ifnet *ifp, struct mbuf *m, * packet. */ if (mst == NULL) { + m_freem(m); error = EAGAIN; goto done; } @@ -263,6 +264,7 @@ ip_output_send(struct inpcb *inp, struct ifnet *ifp, struct mbuf *m, KASSERT(m->m_pkthdr.rcvif == NULL, ("trying to add a send tag to a forwarded packet")); if (mst->ifp != ifp) { + m_freem(m); error = EAGAIN; goto done; } diff --git a/sys/netinet6/ip6_output.c b/sys/netinet6/ip6_output.c index 209169dbdabd..de9ed673de79 100644 --- a/sys/netinet6/ip6_output.c +++ b/sys/netinet6/ip6_output.c @@ -336,6 +336,7 @@ ip6_output_send(struct inpcb *inp, struct ifnet *ifp, struct ifnet *origifp, * packet. */ if (mst == NULL) { + m_freem(m); error = EAGAIN; goto done; } @@ -360,6 +361,7 @@ ip6_output_send(struct inpcb *inp, struct ifnet *ifp, struct ifnet *origifp, KASSERT(m->m_pkthdr.rcvif == NULL, ("trying to add a send tag to a forwarded packet")); if (mst->ifp != ifp) { + m_freem(m); error = EAGAIN; goto done; }
