On Mon, Jun 15, 2020 at 09:39:31AM -0700, Linus Torvalds wrote: > On Mon, Jun 15, 2020 at 5:13 AM Christoph Hellwig <hch@xxxxxx> wrote: > > > > We still need to check if the fѕ is open write, even for the low-level > > helper. > > Is there actually a way to trigger something like this? I'm wondering > if it's worth a WARN_ON_ONCE()? > > It doesn't sound sensible to have some kernel functionality try to > write to a file it didn't open for write, and sounds like a kernel bug > if this case were to ever trigger.. Yes, this would be bug in the calling code.