In the Linux kernel, the following vulnerability has been resolved: ntfs: ->d_compare() must not block ... so don't use __getname() there. Switch it (and ntfs_d_hash(), while we are at it) to kmalloc(PATH_MAX, GFP_NOWAIT). Yes, ntfs_d_hash() almost certainly can do with smaller allocations, but let ntfs folks deal with that - keep the allocation size as-is for now. Stop abusing names_cachep in ntfs, period - various uses of that thing in there have nothing to do with pathnames; just use k[mz]alloc() and be done with that. For now let's keep sizes as-in, but AFAICS none of the users actually want PATH_MAX.
https://git.kernel.org/stable/c/fb4b1f969ba01fa1d4088467a02fc1e5f0806710
https://git.kernel.org/stable/c/ca2a04e84af79596e5cd9cfe697d5122ec39c8ce
https://git.kernel.org/stable/c/142c444a395f4d26055c8a4473e228bb86283f1e