The discrepancy between 'df' and 'du' along with the inability to create new files, despite apparent available disk space, points to inode exhaustion. 'df' reports total disk space including used inodes, while 'du' reports actual file data usage. Inode exhaustion occurs when all the available inodes are in use; new files cannot be created even if physical space is available. A corrupted filesystem would also prevent new files from being created, but wouldn't normally cause the discrepancies between 'df' and 'du' focused on inodes. A full '/tmp' directory would cause issues with file creation but is more likely to be related to space, not inodes, and rogue processes consuming disk space would not directly prevent new file creation if inodes were still available.