On Mon, Feb 14, 2022 at 12:01:05PM -0800, Linus Torvalds wrote: > On Mon, Feb 14, 2022 at 11:46 AM Arnd Bergmann <arnd@xxxxxxxxxx> wrote: > > > > As Al pointed out, they turned out to be necessary on sparc64, but the only > > definitions are on sparc64 and x86, so it's possible that they serve a similar > > purpose here, in which case changing the limit from TASK_SIZE to > > TASK_SIZE_MAX is probably wrong as well. > > x86-64 has always(*) used TASK_SIZE_MAX for access_ok(), and the > get_user() assembler implementation does the same. > > I think any __range_not_ok() users that use TASK_SIZE are entirely > historical, and should be just fixed. IIRC, that was mostly userland stack trace collection in perf. I'll try to dig in archives and see what shows up - it's been a while ago...
