The async dosmode implementation has a fallback to sync processing which is triggered if SMB_VFS_GET_DOS_ATTRIBUTES_RECV() returns NT_STATUS_NOT_IMPLEMENTED. The code creates a new struct smb_filename by calling synthetic_smb_fname() to construct an absolute path, but it passes NULL to the struct stat_ex parameter of synthetic_smb_fname() which means when this path is passed to dosmode(), the VALID_STAT() check in dosmode() fires. Have patch, need bugnumber.
Created attachment 15608 [details] Patch for 4.10 and 4.11 cherry-picked from master
Re-assigning to Karolin for inclusion in 4.11.next, 4.10.next.
(In reply to Jeremy Allison from comment #2) Pushed to autobuild-v4-{11,10}-test.
(In reply to Karolin Seeger from comment #3) Pushed to both branches. Closing out bug report. Thanks!