Snap for 4930082 from 75057f07bd7ad967a6cb22a1225b2a2b4121b390 to pi-qpr1-release

Change-Id: I11d01be815265300419f136698a45cd447f1f34f

2 files changed, 20 insertions, 5 deletions

diff --git a/server/NetlinkListener.cpp b/server/NetlinkListener.cpp
index 82ed6d86..38d12df1 100644
--- a/server/NetlinkListener.cpp
+++ b/server/NetlinkListener.cpp
@@ -107,7 +107,7 @@ Status NetlinkListener::run() {
 
     const auto& sys = sSyscalls.get();
     const std::array<Fd, 2> fds{{{mEvent}, {mSock}}};
-    const int events = POLLIN | POLLRDHUP | POLLERR | POLLHUP;
+    const int events = POLLIN;
     const double timeout = 3600;
     while (true) {
         ASSIGN_OR_RETURN(auto revents, sys.ppoll(fds, events, timeout));
@@ -115,11 +115,15 @@ Status NetlinkListener::run() {
         if (revents[0] & POLLIN) {
             break;
         }
-        if (revents[1] & POLLIN) {
+        if (revents[1] & (POLLIN|POLLERR)) {
             auto rx = sys.recvfrom(mSock, makeSlice(rxbuf), 0);
-            if (rx.status().code() == ENOBUFS) {
-                // Ignore ENOBUFS - the socket is still usable
-                // TODO: Users other than NFLOG may need to know about this
+            int err = rx.status().code();
+            if (err) {
+                // Ignore errors. The only error we expect to see here is ENOBUFS, and there's
+                // nothing we can do about that. The recvfrom above will already have cleared the
+                // error indication and ensured we won't get EPOLLERR again.
+                // TODO: Consider using NETLINK_NO_ENOBUFS.
+                ALOGE("Failed to read from netlink socket: %s", strerror(err));
                 continue;
             }
             forEachNetlinkMessage(rx.value(), rxHandler);
diff --git a/server/TrafficController.cpp b/server/TrafficController.cpp
index d6a64802..0268f9b0 100644
--- a/server/TrafficController.cpp
+++ b/server/TrafficController.cpp
@@ -80,6 +80,17 @@ StatusOr<std::unique_ptr<NetlinkListenerInterface>> makeSkDestroyListener() {
     const int protocol = NETLINK_INET_DIAG;
     ASSIGN_OR_RETURN(auto sock, sys.socket(domain, type, protocol));
 
+    // TODO: if too many sockets are closed too quickly, we can overflow the socket buffer, and
+    // some entries in mCookieTagMap will not be freed. In order to fix this we would need to
+    // periodically dump all sockets and remove the tag entries for sockets that have been closed.
+    // For now, set a large-enough buffer that we can close hundreds of sockets without getting
+    // ENOBUFS and leaking mCookieTagMap entries.
+    int rcvbuf = 512 * 1024;
+    auto ret = sys.setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &rcvbuf, sizeof(rcvbuf));
+    if (!ret.ok()) {
+        ALOGW("Failed to set SkDestroyListener buffer size to %d: %s", rcvbuf, ret.msg().c_str());
+    }
+
     sockaddr_nl addr = {
         .nl_family = AF_NETLINK,
         .nl_groups = 1 << (SKNLGRP_INET_TCP_DESTROY - 1) | 1 << (SKNLGRP_INET_UDP_DESTROY - 1) |