From cb7c1cddc588895f27b12003a7c125db0a442a1a Mon Sep 17 00:00:00 2001
From: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Date: Mon, 25 Feb 2019 17:05:01 +0300
Subject: [PATCH] tools: console: add missing locks in callbacks

Stream/fd callbacks accessing console object are called from the
event loop thread and the console object is also accessed from
the main thread so we are better add locking to handlers.

Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
---
 tools/virsh-console.c | 35 +++++++++++++++++++++++++----------
 1 file changed, 25 insertions(+), 10 deletions(-)

diff --git a/tools/virsh-console.c b/tools/virsh-console.c
index 928922135f..3dae70799e 100644
--- a/tools/virsh-console.c
+++ b/tools/virsh-console.c
@@ -137,6 +137,8 @@ virConsoleEventOnStream(virStreamPtr st,
 {
     virConsolePtr con = opaque;
 
+    virObjectLock(con);
+
     if (events & VIR_STREAM_EVENT_READABLE) {
         size_t avail = con->streamToTerminal.length -
             con->streamToTerminal.offset;
@@ -146,7 +148,7 @@ virConsoleEventOnStream(virStreamPtr st,
             if (VIR_REALLOC_N(con->streamToTerminal.data,
                               con->streamToTerminal.length + 1024) < 0) {
                 virConsoleShutdown(con);
-                return;
+                goto cleanup;
             }
             con->streamToTerminal.length += 1024;
             avail += 1024;
@@ -157,10 +159,10 @@ virConsoleEventOnStream(virStreamPtr st,
                             con->streamToTerminal.offset,
                             avail);
         if (got == -2)
-            return; /* blocking */
+            goto cleanup; /* blocking */
         if (got <= 0) {
             virConsoleShutdown(con);
-            return;
+            goto cleanup;
         }
         con->streamToTerminal.offset += got;
         if (con->streamToTerminal.offset)
@@ -176,10 +178,10 @@ virConsoleEventOnStream(virStreamPtr st,
                              con->terminalToStream.data,
                              con->terminalToStream.offset);
         if (done == -2)
-            return; /* blocking */
+            goto cleanup; /* blocking */
         if (done < 0) {
             virConsoleShutdown(con);
-            return;
+            goto cleanup;
         }
         memmove(con->terminalToStream.data,
                 con->terminalToStream.data + done,
@@ -201,6 +203,9 @@ virConsoleEventOnStream(virStreamPtr st,
         events & VIR_STREAM_EVENT_HANGUP) {
         virConsoleShutdown(con);
     }
+
+ cleanup:
+    virObjectUnlock(con);
 }
 
 
@@ -212,6 +217,8 @@ virConsoleEventOnStdin(int watch ATTRIBUTE_UNUSED,
 {
     virConsolePtr con = opaque;
 
+    virObjectLock(con);
+
     if (events & VIR_EVENT_HANDLE_READABLE) {
         size_t avail = con->terminalToStream.length -
             con->terminalToStream.offset;
@@ -221,7 +228,7 @@ virConsoleEventOnStdin(int watch ATTRIBUTE_UNUSED,
             if (VIR_REALLOC_N(con->terminalToStream.data,
                               con->terminalToStream.length + 1024) < 0) {
                 virConsoleShutdown(con);
-                return;
+                goto cleanup;
             }
             con->terminalToStream.length += 1024;
             avail += 1024;
@@ -234,15 +241,15 @@ virConsoleEventOnStdin(int watch ATTRIBUTE_UNUSED,
         if (got < 0) {
             if (errno != EAGAIN)
                 virConsoleShutdown(con);
-            return;
+            goto cleanup;
         }
         if (got == 0) {
             virConsoleShutdown(con);
-            return;
+            goto cleanup;
         }
         if (con->terminalToStream.data[con->terminalToStream.offset] == con->escapeChar) {
             virConsoleShutdown(con);
-            return;
+            goto cleanup;
         }
 
         con->terminalToStream.offset += got;
@@ -256,6 +263,9 @@ virConsoleEventOnStdin(int watch ATTRIBUTE_UNUSED,
         events & VIR_EVENT_HANDLE_HANGUP) {
         virConsoleShutdown(con);
     }
+
+ cleanup:
+    virObjectUnlock(con);
 }
 
 
@@ -267,6 +277,8 @@ virConsoleEventOnStdout(int watch ATTRIBUTE_UNUSED,
 {
     virConsolePtr con = opaque;
 
+    virObjectLock(con);
+
     if (events & VIR_EVENT_HANDLE_WRITABLE &&
         con->streamToTerminal.offset) {
         ssize_t done;
@@ -277,7 +289,7 @@ virConsoleEventOnStdout(int watch ATTRIBUTE_UNUSED,
         if (done < 0) {
             if (errno != EAGAIN)
                 virConsoleShutdown(con);
-            return;
+            goto cleanup;
         }
         memmove(con->streamToTerminal.data,
                 con->streamToTerminal.data + done,
@@ -299,6 +311,9 @@ virConsoleEventOnStdout(int watch ATTRIBUTE_UNUSED,
         events & VIR_EVENT_HANDLE_HANGUP) {
         virConsoleShutdown(con);
     }
+
+ cleanup:
+    virObjectUnlock(con);
 }