Charles-François Natali <neolo...@free.fr> added the comment: > So Python starts by removing the .tmp file, but it fails if another > process is already writing into the .tmp file. In this case, we do > nothing, which is not a problem: the other process will create the > file.
unlink() does not fail, even if the file is open by another process with O_EXCL! Therefore there's a race: - process 1 opens file.tmp - process 2 unlinks file.tmp - process 2 opens file.tmp: this succeeds, since he just removed the file opened by proc 1 - process 1, which was working on its deleted file handle, is done, and renames file.tmp to file: except that it rename the file process 2 is in the middle of writing - game over, file corrupted > Attached patch implements the same algorithm than import.c in > importlib. Same race. The current implementations are safe, both Python/import.c and Lib/importlib/_bootstrap.py The only problem is that since import.c uses mkstemp, the file is created with mode 0600. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue13303> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
