Prevent invalid free of workspace name

An allocated pointer was incremented before being freed in
`sway/workspace.c` which led to an invalid free. This has been fixed by
keeping the pointer in place and moving the data instead.

Fixes #1548

1 files changed, 3 insertions, 2 deletions

diff --git a/sway/workspace.c b/sway/workspace.c
index e0367190..42525f3d 100644
--- a/sway/workspace.c
+++ b/sway/workspace.c
@@ -68,8 +68,9 @@ char *workspace_next_name(const char *output_name) {
                         sway_log(L_DEBUG, "Got valid workspace command for target: '%s'", name);
                         char *_target = strdup(name);
                         strip_quotes(_target);
-                        while (isspace(*_target))
-                                _target++;
+                        while (isspace(*_target)) {
+                                memmove(_target, _target+1, strlen(_target+1));
+                        }
 
                         // Make sure that the command references an actual workspace
                         // not a command about workspaces