Fix concurrency issue in server socket handling

Do-not-call-gpm_grab_sock-twice.patch

@@ -0,0 +1,59 @@
+From 99062c344b7dba58ab8db0fad5520a754d9a6841 Mon Sep 17 00:00:00 2001
+From: Simo Sorce <simo@redhat.com>
+Date: Thu, 26 Oct 2017 16:59:18 -0400
+Subject: [PATCH] Do not call gpm_grab_sock() twice
+
+In the gpm_get_ctx() call, we unnecessarily call gpm_grab_sock() which
+would cause the lock to be held by one thread and never released.  We
+already call gpm_grab_sock() as the first thing after gpm_get_ctx() in
+gpm_make_call(), plus gpm_make_call() properly releases the socket
+once done.
+
+This corrects the deadlock fix in
+461a5fa9f91a2753ebeef6323a64239c35e2f250, which incorrectly released
+the lock we wanted to grab.  This caused the socket to not be locked
+to our thread.  Another thread could come along and change the global
+ctx while we were still using the socket from another thread, causing
+concurrency issues as only one request can be in flight on any given
+socket at the same time.
+
+In special cases where the "thread" uid/gid changes (like in
+rpc.gssd), we end up closing the socket while we are still waiting for
+an answer from the server, causing additional issues and confusion.
+
+[rharwood@redhat.com: squashed 2 commits; minor edits accordingly]
+Signed-off-by: Simo Sorce <simo@redhat.com>
+Reviewed-by: Robbie Harwood <rharwood@redhat.com>
+Merges: #218
+(cherry picked from commit 8590c5dbc6fa07d0c366df23b982a4b6b9ffc259)
+---
+ proxy/src/client/gpm_common.c | 9 +++------
+ 1 file changed, 3 insertions(+), 6 deletions(-)
+
+diff --git a/proxy/src/client/gpm_common.c b/proxy/src/client/gpm_common.c
+index 994bd80..8837add 100644
+--- a/proxy/src/client/gpm_common.c
++++ b/proxy/src/client/gpm_common.c
+@@ -163,7 +163,9 @@ static int gpm_grab_sock(struct gpm_ctx *gpmctx)
+         ret = gpm_open_socket(gpmctx);
+     }
+ 
+-    pthread_mutex_unlock(&gpmctx->lock);
++    if (ret) {
++        pthread_mutex_unlock(&gpmctx->lock);
++    }
+     return ret;
+ }
+ 
+@@ -512,11 +514,6 @@ static struct gpm_ctx *gpm_get_ctx(void)
+ 
+     pthread_once(&gpm_init_once_control, gpm_init_once);
+ 
+-    ret = gpm_grab_sock(&gpm_global_ctx);
+-    if (ret) {
+-        return NULL;
+-    }
+-
+     return &gpm_global_ctx;
+ }
+ 

Emit-debug-on-queue-errors.patch

@@ -0,0 +1,26 @@
+From d5f22a1c2ad70ff1e7922c91086a04f0dc31db58 Mon Sep 17 00:00:00 2001
+From: Simo Sorce <simo@redhat.com>
+Date: Thu, 26 Oct 2017 11:47:54 -0400
+Subject: [PATCH] Emit debug on queue errors
+
+Signed-off-by: Simo Sorce <simo@redhat.com>
+Reviewed-by: Robbie Harwood <rharwood@redhat.com>
+Merges: #218
+(cherry picked from commit af666affbd4735ba437e3d89d9e22984a556ed16)
+---
+ proxy/src/gp_workers.c | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/proxy/src/gp_workers.c b/proxy/src/gp_workers.c
+index 2a33c21..18f38f6 100644
+--- a/proxy/src/gp_workers.c
++++ b/proxy/src/gp_workers.c
+@@ -314,6 +314,8 @@ static void gp_handle_reply(verto_ctx *vctx, verto_ev *ev)
+         case GP_QUERY_IN:
+             /* ?! fallback and kill client conn */
+         case GP_QUERY_ERR:
++            GPDEBUGN(3, "[status] Handling query error, terminating CID %d.\n",
++                     gp_conn_get_cid(q->conn));
+             gp_conn_free(q->conn);
+             gp_query_free(q, true);
+             break;

gssproxy.spec

@@ -1,6 +1,6 @@
 Name:		gssproxy
 Version:	0.7.0
-Release:	21%{?dist}
+Release:	22%{?dist}
 Summary:	GSSAPI Proxy
 
 Group:		System Environment/Libraries
@@ -35,6 +35,8 @@ Patch17: Fix-error-handling-in-gpm_send_buffer-gpm_recv_buffe.patch
 Patch18: Handle-outdated-encrypted-ccaches.patch
 Patch19: Fix-error-handling-in-gp_config_from_dir.patch
 Patch20: Fix-silent-crash-with-duplicate-config-sections.patch
+Patch21: Emit-debug-on-queue-errors.patch
+Patch22: Do-not-call-gpm_grab_sock-twice.patch
 
 ### Dependencies ###
 Requires: krb5-libs >= 1.12.0
@@ -132,6 +134,9 @@ rm -rf %{buildroot}
 %systemd_postun_with_restart gssproxy.service
 
 %changelog
+* Fri Oct 27 2017 Robbie Harwood <rharwood@redhat.com> - 0.7.0-22
+- Fix concurrency issue in server socket handling
+
 * Mon Oct 02 2017 Robbie Harwood <rharwood@redhat.com> - 0.7.0-21
 - Off-by-one error fix in selinux-policy version