samba-bugs@samba.org
2008-Oct-09 07:26 UTC
DO NOT REPLY [Bug 5820] New: rsync does not replace symlink atomically
https://bugzilla.samba.org/show_bug.cgi?id=5820 Summary: rsync does not replace symlink atomically Product: rsync Version: 3.0.4 Platform: All OS/Version: All Status: NEW Severity: normal Priority: P3 Component: core AssignedTo: wayned@samba.org ReportedBy: rsync@sysoev.ru QAContact: rsync-qa@samba.org rsync does not replace symlink atomically, i.e, first it unlinks an old symlink and then creates a new symlink. There is short time when symlink does not exist at all. The attached patch against 3.0.4 fixes the issue. However, it has been tested on FreeBSD only. The patch is also available on http://sysoev.ru/tmp/rsync.symlink.patch --- generator.c 2008-08-31 20:51:29.000000000 +0400 +++ generator.c 2008-10-08 23:10:17.000000000 +0400 @@ -1556,9 +1556,40 @@ if (remove_source_files == 1) goto return_with_success; goto cleanup; + } else { + char fnametmp[MAXPATHLEN]; + + /* Replace the symlink atomically. */ + if (!get_tmpname(fnametmp, fname)) + goto cleanup; + if (!mktemp(fnametmp)) + goto cleanup; + if (do_symlink(sl, fnametmp) != 0) { + rsyserr(FERROR_XFER, errno, "symlink %s -> \"%s\" failed", + full_fname(fnametmp), sl); + goto cleanup; + } + set_file_attrs(fnametmp, file, NULL, NULL, 0); + if (do_rename(fnametmp, fname) != 0) { + rsyserr(FERROR_XFER, errno, "rename %s -> %s failed", + full_fname(fnametmp), full_fname(fname)); + goto cleanup; + } + if (itemizing) { + itemize(fname, file, ndx, statret, &sx, + ITEM_LOCAL_CHANGE|ITEM_REPORT_CHANGE, 0, NULL); + } + if (verbose) + rprintf(code, "%s -> %s\n", fname, sl); +#ifdef SUPPORT_HARD_LINKS + if (preserve_hard_links && F_IS_HLINKED(file)) + finish_hard_link(file, fname, ndx, NULL, itemizing, code, -1); +#endif + if (remove_source_files) + goto return_with_success; + goto cleanup; } - /* Not the right symlink (or not a symlink), so - * delete it. */ + /* Not not a symlink, so delete it. */ if (delete_item(fname, sx.st.st_mode, del_opts | DEL_FOR_SYMLINK) != 0) goto cleanup; } else if (basis_dir[0] != NULL) { -- Configure bugmail: https://bugzilla.samba.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the QA contact for the bug, or are watching the QA contact.
samba-bugs@samba.org
2008-Oct-09 17:14 UTC
DO NOT REPLY [Bug 5820] rsync does not replace symlink atomically
https://bugzilla.samba.org/show_bug.cgi?id=5820 ------- Comment #1 from matt@mattmccutchen.net 2008-10-09 12:14 CST ------- The same issue exists with device/special files and also when replacing a file with one of a different type (e.g., a regular file with a symlink). Let's find a way to solve this without duplicating a lot of code. See also the --stage-all option of bug 4561 comment 6. -- Configure bugmail: https://bugzilla.samba.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the QA contact for the bug, or are watching the QA contact.