Re: random canary bytes for malloc

2020-10-04 Thread Theo Buehler
On Sun, Oct 04, 2020 at 09:51:14AM +0200, Otto Moerbeek wrote: > On Tue, Sep 29, 2020 at 08:17:54AM +0200, Otto Moerbeek wrote: > > > Hi, > > > > until now, canary bytes (used by the C olption) were the same as the > > bytes used to junk (0xfd). This means that certain overwrites are not > >

Re: random canary bytes for malloc

2020-10-04 Thread Otto Moerbeek
On Tue, Sep 29, 2020 at 08:17:54AM +0200, Otto Moerbeek wrote: > Hi, > > until now, canary bytes (used by the C olption) were the same as the > bytes used to junk (0xfd). This means that certain overwrites are not > detected, like setting the high bit. > > This makes the byte value used to

random canary bytes for malloc

2020-09-29 Thread Otto Moerbeek
Hi, until now, canary bytes (used by the C olption) were the same as the bytes used to junk (0xfd). This means that certain overwrites are not detected, like setting the high bit. This makes the byte value used to write canaries random. I do not want to complicate the code to handle all