[PATCH] VFS: renaming across file systems no longer possible?

[Rainer Link]

Hi,


I received a bug report for samba-vscan today that moving (correctly
spoken renaming) an infected file into quarantine across file system does 
not work with Samba 3.0. 

So, I had a look at vfs-wrap.c in Samba 2.2.x and Samba 3.0 - the
copy_reg function is missing in vfs-wrap.c of Samba 3.0. I tried
to find out the reason for that in CVS log, but was not able to
find it (moreover, I was too stupid to find the "branch off" the
Samba 3.0 code, as the samba-3-split tag is too late ...).

Any reason why the code in Samba 3.0 is different here? I attached
a diff which is just a cut&paste from the SAMBA-2.2 code. 

Thanks.

best regards,
Rainer Link

-------------- next part --------------
Index: vfs-wrap.c
===================================================================
RCS file: /cvsroot/samba/source/smbd/vfs-wrap.c,v
retrieving revision 1.37.2.12
diff -u -r1.37.2.12 vfs-wrap.c
--- vfs-wrap.c	7 Aug 2003 21:47:46 -0000	1.37.2.12
+++ vfs-wrap.c	21 Nov 2003 16:22:55 -0000
@@ -237,12 +237,100 @@
 	return result;
 }
 
+/*********************************************************
+ For rename across filesystems Patch from Warren Birnbaum
+ <warrenb at hpcvscdp.cv.hp.com>
+**********************************************************/
+static int copy_reg(const char *source, const char *dest)
+{
+        SMB_STRUCT_STAT source_stats;
+        int saved_errno;
+        int ifd = -1;
+        int ofd = -1;
+
+        if (sys_lstat (source, &source_stats) == -1)
+                return -1;
+
+        if (!S_ISREG (source_stats.st_mode))
+                return -1;
+
+        if((ifd = sys_open (source, O_RDONLY, 0)) < 0)
+                return -1;
+
+        if (unlink (dest) && errno != ENOENT)
+                return -1;
+
+#ifdef O_NOFOLLOW
+        if((ofd = sys_open (dest, O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW, 0600)) < 0 )
+#else
+        if((ofd = sys_open (dest, O_WRONLY | O_CREAT | O_TRUNC , 0600)) < 0 )
+#endif
+                goto err;
+
+        if (transfer_file(ifd, ofd, (size_t)-1) == -1)
+                goto err;
+
+        /*
+         * Try to preserve ownership.  For non-root it might fail, but that's ok.
+         * But root probably wants to know, e.g. if NFS disallows it.
+         */
+
+        if ((fchown(ofd, source_stats.st_uid, source_stats.st_gid) == -1) && (errno != EPERM))
+                goto err;
+
+        /*
+         * fchown turns off set[ug]id bits for non-root,
+         * so do the chmod last.
+         */
+
+#if defined(HAVE_FCHMOD)
+        if (fchmod (ofd, source_stats.st_mode & 07777))
+#else
+        if (chmod (dest, source_stats.st_mode & 07777))
+#endif
+                goto err;
+
+        if (close (ifd) == -1)
+                goto err;
+
+        if (close (ofd) == -1)
+                return -1;
+
+        /* Try to copy the old file's modtime and access time.  */
+        {
+                struct utimbuf tv;
+
+                tv.actime = source_stats.st_atime;
+                tv.modtime = source_stats.st_mtime;
+                utime (dest, &tv);
+        }
+
+        if (unlink (source) == -1)
+                return -1;
+
+        return 0;
+
+  err:
+        saved_errno = errno;
+        if (ifd != -1)
+                close(ifd);
+        if (ofd != -1)
+                close(ofd);
+        errno = saved_errno;
+        return -1;
+}
+
+
 int vfswrap_rename(vfs_handle_struct *handle, connection_struct *conn, const char *old, const char *new)
 {
     int result;
 
     START_PROFILE(syscall_rename);
     result = rename(old, new);
+    if (errno == EXDEV) {
+	/* Rename across filesystems needed. */
+        result = copy_reg(oldname, newname);
+    }
     END_PROFILE(syscall_rename);
     return result;
 }