features/locks: error-out {inode,entry}lk fops with all-zero lk-owner

Problem:
Sometimes we find that developers forget to assign lk-owner for an
inodelk/entrylk/lk before writing code to wind these fops. locks
xlator at the moment allows this operation. This leads to multiple
threads in the same client being able to get locks on the inode
because lk-owner is same and transport is same. So isolation
with locks can't be achieved.

Fix:
Disallow locks with lk-owner zero.

fixes bz#1624701
Change-Id: I1c816280cffd150ebb392e3dcd4d21007cdd767f
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/xlators/features/locks/src/entrylk.c b/xlators/features/locks/src/entrylk.c
index ced5eca2749..9d6a4c93057 100644
--- a/xlators/features/locks/src/entrylk.c
+++ b/xlators/features/locks/src/entrylk.c
@@ -39,13 +39,20 @@ __pl_entrylk_ref(pl_entry_lock_t *lock)
 
 static pl_entry_lock_t *
 new_entrylk_lock(pl_inode_t *pinode, const char *basename, entrylk_type type,
-                 const char *domain, call_frame_t *frame, char *conn_id)
+                 const char *domain, call_frame_t *frame, char *conn_id,
+                 int32_t *op_errno)
 {
     pl_entry_lock_t *newlock = NULL;
 
+    if (!pl_is_lk_owner_valid(&frame->root->lk_owner, frame->root->client)) {
+        *op_errno = EINVAL;
+        goto out;
+    }
+
     newlock = GF_CALLOC(1, sizeof(pl_entry_lock_t),
                         gf_locks_mt_pl_entry_lock_t);
     if (!newlock) {
+        *op_errno = ENOMEM;
         goto out;
     }
 
@@ -793,10 +800,9 @@ pl_common_entrylk(call_frame_t *frame, xlator_t *this, const char *volume,
     entrylk_trace_in(this, frame, volume, fd, loc, basename, cmd, type);
 
     reqlock = new_entrylk_lock(pinode, basename, type, dom->domain, frame,
-                               conn_id);
+                               conn_id, &op_errno);
     if (!reqlock) {
         op_ret = -1;
-        op_errno = ENOMEM;
         goto unwind;
     }