Possible race condition between cleanup and dereferencing

Signed-off-by: shishir gowda <shishirng@gluster.com>
Signed-off-by: Vijay Bellur <vijay@dev.gluster.com>

BUG: 1760 ()
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=1760

8 files changed, 22 insertions, 1 deletions

diff --git a/xlators/cluster/stripe/src/stripe.c b/xlators/cluster/stripe/src/stripe.c
index a8ac55aa4..d37f38ca6 100644
--- a/xlators/cluster/stripe/src/stripe.c
+++ b/xlators/cluster/stripe/src/stripe.c
@@ -3941,6 +3941,7 @@ fini (xlator_t *this)
 
         priv = this->private;
         if (priv) {
+                this->private = NULL;
                 if (priv->xl_array)
                         GF_FREE (priv->xl_array);
 
diff --git a/xlators/debug/io-stats/src/io-stats.c b/xlators/debug/io-stats/src/io-stats.c
index e87334364..2061d9bc9 100644
--- a/xlators/debug/io-stats/src/io-stats.c
+++ b/xlators/debug/io-stats/src/io-stats.c
@@ -1695,6 +1695,10 @@ fini (xlator_t *this)
 
         conf = this->private;
 
+        if (!conf)
+                return;
+        this->private = NULL;
+
         GF_FREE(conf);
 
         gf_log (this->name, GF_LOG_NORMAL,
diff --git a/xlators/encryption/rot-13/src/rot-13.c b/xlators/encryption/rot-13/src/rot-13.c
index 98bfd1b5a..39549d8be 100644
--- a/xlators/encryption/rot-13/src/rot-13.c
+++ b/xlators/encryption/rot-13/src/rot-13.c
@@ -181,6 +181,9 @@ fini (xlator_t *this)
 {
 	rot_13_private_t *priv = this->private;
 
+        if (!priv)
+                return;
+        this->private = NULL;
 	GF_FREE (priv);
 
 	return;
diff --git a/xlators/features/locks/src/posix.c b/xlators/features/locks/src/posix.c
index 36c399c11..29b3bb079 100644
--- a/xlators/features/locks/src/posix.c
+++ b/xlators/features/locks/src/posix.c
@@ -1885,6 +1885,9 @@ fini (xlator_t *this)
         posix_locks_private_t *priv = NULL;
 
         priv = this->private;
+        if (!priv)
+                return 0;
+        this->private = NULL;
         GF_FREE (priv);
 
         return 0;
diff --git a/xlators/performance/stat-prefetch/src/stat-prefetch.c b/xlators/performance/stat-prefetch/src/stat-prefetch.c
index 972afe313..0a984908f 100644
--- a/xlators/performance/stat-prefetch/src/stat-prefetch.c
+++ b/xlators/performance/stat-prefetch/src/stat-prefetch.c
@@ -777,7 +777,7 @@ sp_cache_add_entries (sp_cache_t *cache, gf_dirent_t *entries)
         sp_private_t *priv = NULL;
 
         this = cache->this;
-        if (this)
+        if (this && this->private)
                 priv = this->private;
 
         LOCK (&cache->lock);
@@ -3676,6 +3676,7 @@ fini (xlator_t *this)
                                 mem_pool_destroy (priv->mem_pool);
                         LOCK_DESTROY (&priv->lock);
                         GF_FREE (priv);
+                        this->private = NULL;
                 }
         }
 out:
diff --git a/xlators/performance/write-behind/src/write-behind.c b/xlators/performance/write-behind/src/write-behind.c
index 8a4be0f7f..42fc0bb7e 100644
--- a/xlators/performance/write-behind/src/write-behind.c
+++ b/xlators/performance/write-behind/src/write-behind.c
@@ -3009,6 +3009,9 @@ fini (xlator_t *this)
 {
         wb_conf_t *conf = this->private;
 
+        if (!conf)
+                return;
+        this->private = NULL;
         GF_FREE (conf);
         return;
 }
diff --git a/xlators/protocol/legacy/transport/socket/src/socket.c b/xlators/protocol/legacy/transport/socket/src/socket.c
index 7b68e3a3e..854529ca2 100644
--- a/xlators/protocol/legacy/transport/socket/src/socket.c
+++ b/xlators/protocol/legacy/transport/socket/src/socket.c
@@ -1547,6 +1547,9 @@ fini (transport_t *this)
 {
         socket_private_t *priv = this->private;
 
+        if (!priv)
+                return;
+        this->private = NULL;
         gf_log (this->xl->name, GF_LOG_TRACE,
                 "transport %p destroyed", this);
 
diff --git a/xlators/storage/posix/src/posix.c b/xlators/storage/posix/src/posix.c
index ef5dae218..51e4230ae 100644
--- a/xlators/storage/posix/src/posix.c
+++ b/xlators/storage/posix/src/posix.c
@@ -4438,6 +4438,9 @@ void
 fini (xlator_t *this)
 {
         struct posix_private *priv = this->private;
+        if (!priv)
+                return;
+        this->private = NULL;
         sys_lremovexattr (priv->base_path, "trusted.glusterfs.test");
         GF_FREE (priv);
         return;