On 12/29/20 10:11 AM, Randy Dunlap wrote: > On 12/29/20 10:01 AM, Toralf Förster wrote: >> On 12/23/20 2:50 AM, Randy Dunlap wrote: >>>> What motivates this change? Is there any reason to think this can >>>> happen? >>> Spotted in the wild: >> I run 2 hardened Gentoo systems, a server and a desktop. >> >> I patched the server with this: >> >> mr-fox ~ # cat ubsan.patch >> --- linux-5.10.1.orig/mm/readahead.c >> +++ linux-5.10.1/mm/readahead.c >> @@ -310,7 +310,11 @@ void force_page_cache_ra(struct readahea >> */ >> static unsigned long get_init_ra_size(unsigned long size, unsigned >> long max) >> { >> - unsigned long newsize = roundup_pow_of_two(size); >> + unsigned long newsize; >> + >> + if (!size) >> + size = 32; >> + newsize = roundup_pow_of_two(size); >> >> if (newsize <= max / 32) >> newsize = newsize * 4; >> >> >> >> and the issue did no longer occurred at the server (5.10.2). >> >> I did not patched the desktop system and the issue occurred still 3 >> times since 21th of december (5.10.2/3) > > Yes, that's the patch that I posted on 2020-DEC-22. > > Looks like I should submit a real patch for that. > > thanks. > Hi Toralf, Do you want either or both of your Reported-by: and Tested-by: on the patch? thanks. -- ~Randy