On Sun, 28 Apr 2024 21:04:50 -0700 Luis Chamberlain <mcgrof@xxxxxxxxxx> wrote: > On Thu, Apr 25, 2024 at 02:01:26PM -0700, Andrew Morton wrote: > > On Wed, 24 Apr 2024 15:54:48 -0700 Luis Chamberlain <mcgrof@xxxxxxxxxx> wrote: > > > > > If the file entry is too long we may easily end up going out of bounds > > > and crash after strsep() on sscanf(). > > > > > > > Can you explain why? I'm not seeing it. > > I couldn't see it either but I just looked at the crash below and > its the only thing I could think of. So I think its when userspace > somehow abuses MAX_INPUT_BUF_SZ a lot somehow. This isn't a good basis for making kernel changes :( Can you investigate a little further please? What actually is present at *buf when your new checks succeed? Could we be seeing 0xNNN,0xNNN and leaving new_order unaltered? Or something.