diff options
| author | Niels de Vos <ndevos@redhat.com> | 2014-12-04 15:40:52 +0100 |
|---|---|---|
| committer | Niels de Vos <ndevos@redhat.com> | 2014-12-12 06:26:02 -0800 |
| commit | 09af313fe6b49b03501939dd9e46b783ca4b5416 (patch) | |
| tree | bbf09664feeaa2dc5f3795e091e6f712c644e143 /xlators/mount | |
| parent | 12c15f47fe68bcf8b32f55f3ca42638fd4eda998 (diff) | |
fuse: protect checking/modifying graph->used with a mutex
While reviewing http://review.gluster.org/#/c/9060/ we noticed that fuse
checks/modifies graph->used in a unlocked way. There is a potential race
in case when fuse_graph_setup() gets called from two different threads
(currently unlikely, but poller/notify() might change in future?).
In libgfapi we came to the conclusion that each glfs structure can be
used to protect the checking/updating of graph->used. In fuse this would
be the fuse_private_t with sync_mutex.
BUG: 1170643
Change-Id: If5ab5468d22fdb92cfb24a469f538f63f12baf78
Signed-off-by: Niels de Vos <ndevos@redhat.com>
Reviewed-on: http://review.gluster.org/9237
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
Diffstat (limited to 'xlators/mount')
| -rw-r--r-- | xlators/mount/fuse/src/fuse-bridge.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/xlators/mount/fuse/src/fuse-bridge.c b/xlators/mount/fuse/src/fuse-bridge.c index 1404b148bd5..e61671829e1 100644 --- a/xlators/mount/fuse/src/fuse-bridge.c +++ b/xlators/mount/fuse/src/fuse-bridge.c @@ -5032,10 +5032,16 @@ fuse_graph_setup (xlator_t *this, glusterfs_graph_t *graph) if (priv->active_subvol == graph->top) return 0; /* This is a valid case */ - if (graph->used) - return 0; + pthread_mutex_lock (&priv->sync_mutex); + { + if (graph->used) { + pthread_mutex_unlock (&priv->sync_mutex); + return 0; + } - graph->used = 1; + graph->used = 1; + } + pthread_mutex_unlock (&priv->sync_mutex); itable = inode_table_new (0, graph->top); if (!itable) |