clang-scan: fix multiple issues

* Buffer overflow issue in glusterfsd
* Null argument passed to function expecting non-null (event-epoll)
* Make sure the op_ret value is set in macro (posix)

Updates: bz#1622665

Change-Id: I32b378fc40a5e3ee800c0dfbc13335d44c9db9ac
Signed-off-by: Amar Tumballi <amarts@redhat.com>

4 files changed, 19 insertions, 8 deletions

diff --git a/xlators/storage/posix/src/posix-entry-ops.c b/xlators/storage/posix/src/posix-entry-ops.c
index 11ce9d69540..34dff4bd726 100644
--- a/xlators/storage/posix/src/posix-entry-ops.c
+++ b/xlators/storage/posix/src/posix-entry-ops.c
@@ -1725,7 +1725,7 @@ posix_rename (call_frame_t *frame, xlator_t *this,
                 }
 
                 if ((xdata) && (dict_get (xdata, GET_LINK_COUNT))
-                    && (real_newpath) && (was_present)) {
+                    && (real_newpath) && (was_present) && ctx_new) {
                         pthread_mutex_lock (&ctx_new->pgfid_lock);
                         locked = _gf_true;
                         get_link_count = _gf_true;
diff --git a/xlators/storage/posix/src/posix-helpers.c b/xlators/storage/posix/src/posix-helpers.c
index d521d80e8aa..99be6366e11 100644
--- a/xlators/storage/posix/src/posix-helpers.c
+++ b/xlators/storage/posix/src/posix-helpers.c
@@ -3390,7 +3390,7 @@ posix_cs_maintenance (xlator_t *this, fd_t *fd, loc_t *loc, int *pfd,
         } else {
                 if (!loc->inode) {
                         ret = 0;
-                        goto unlock;
+                        goto out;
                 }
 
                 LOCK (&loc->inode->lock);
@@ -3450,6 +3450,6 @@ unlock:
                 UNLOCK (&fd->inode->lock);
         else
                 UNLOCK (&loc->inode->lock);
-
+out:
         return ret;
 }
diff --git a/xlators/storage/posix/src/posix-inode-fd-ops.c b/xlators/storage/posix/src/posix-inode-fd-ops.c
index 795f19a1515..64fa5ea7a82 100644
--- a/xlators/storage/posix/src/posix-inode-fd-ops.c
+++ b/xlators/storage/posix/src/posix-inode-fd-ops.c
@@ -1257,13 +1257,14 @@ posix_readlink (call_frame_t *frame, xlator_t *this,
 {
         char *  dest      = NULL;
         int32_t op_ret    = -1;
-        int32_t op_errno  = 0;
+        int32_t op_errno  = EINVAL;
         char *  real_path = NULL;
         struct iatt stbuf = {0,};
 
         DECLARE_OLD_FS_ID_VAR;
 
         VALIDATE_OR_GOTO (frame, out);
+        VALIDATE_OR_GOTO (loc, out);
 
         SET_FS_ID (frame->root->uid, frame->root->gid);
 
@@ -3993,12 +3994,15 @@ int32_t
 posix_removexattr (call_frame_t *frame, xlator_t *this,
                    loc_t *loc, const char *name, dict_t *xdata)
 {
-        int    op_ret     = 0;
-        int    op_errno   = 0;
+        int    op_ret     = -1;
+        int    op_errno   = EINVAL;
         dict_t *xdata_rsp = NULL;
 
+        VALIDATE_OR_GOTO (loc, out);
+
         op_ret = posix_common_removexattr (frame, loc, NULL, name, xdata,
                                            &op_errno, &xdata_rsp);
+out:
         STACK_UNWIND_STRICT (removexattr, frame, op_ret, op_errno, xdata_rsp);
 
         if (xdata_rsp)
@@ -4011,12 +4015,15 @@ int32_t
 posix_fremovexattr (call_frame_t *frame, xlator_t *this,
                     fd_t *fd, const char *name, dict_t *xdata)
 {
-        int32_t op_ret     = 0;
-        int32_t op_errno   = 0;
+        int32_t op_ret     = -1;
+        int32_t op_errno   = EINVAL;
         dict_t  *xdata_rsp = NULL;
 
+        VALIDATE_OR_GOTO (fd, out);
+
         op_ret = posix_common_removexattr (frame, NULL, fd, name, xdata,
                                            &op_errno, &xdata_rsp);
+out:
         STACK_UNWIND_STRICT (fremovexattr, frame, op_ret, op_errno, xdata_rsp);
 
         if (xdata_rsp)
diff --git a/xlators/storage/posix/src/posix-inode-handle.h b/xlators/storage/posix/src/posix-inode-handle.h
index 33d908fa3de..cb315424dd0 100644
--- a/xlators/storage/posix/src/posix-inode-handle.h
+++ b/xlators/storage/posix/src/posix-inode-handle.h
@@ -54,14 +54,18 @@
                 var = NULL;                                             \
         } while (0)
 
+/* TODO: it is not a good idea to change a variable which
+   is not passed to the macro.. Fix it later */
 #define MAKE_INODE_HANDLE(rpath, this, loc, iatt_p) do {                \
         if (!this->private) {                                           \
+                op_ret = -1;                                            \
                 gf_msg ("make_inode_handle", GF_LOG_ERROR, 0,           \
                          P_MSG_INODE_HANDLE_CREATE,                     \
                          "private is NULL, fini is already called");    \
                 break;                                                  \
         }                                                               \
         if (gf_uuid_is_null (loc->gfid)) {                              \
+                op_ret = -1;                                            \
                 gf_msg (this->name, GF_LOG_ERROR, 0,                    \
                         P_MSG_INODE_HANDLE_CREATE,                      \
                         "null gfid for path %s", (loc)->path);          \