On 2025/04/05 11:43:40 +0300, Eli Zaretskii wrote: > Ping! Werner, do you plan on submitting a modified patch? What is about the attacheds patch ... here I go with the latest manual page ioctl_tty(2) as well if the macro MAP_DROPPABLE is not defined then the value 0x08 is used. > > From: Philipp Stephani > > Date: Tue, 25 Mar 2025 17:22:22 +0100 > > Cc: Eli Zaretskii , > > 77232@debbugs.gnu.org > > > > > > > > > Am 25.03.2025 um 16:24 schrieb Dr. Werner Fink : > > > > > > On 2025/03/25 16:06:39 +0100, Philipp Stephani wrote: > > >>>> #endif > > >>>> > > >>>> +/* https://github.com/torvalds/linux/commit/9651fcedf7b92d3f7f1ab179e8ab55b85ee10fc1 */ > > >>>> +#ifndef MAP_DROPPABLE > > >>>> +#define MAP_DROPPABLE 0x0 > > >> > > >> Shouldn't this be 0x08? At least that's how it's defined in mman.h. > > > > > > If the kernel does not know (means header does not know) we should not > > > set an unknown flags as this will fail also (IMHO). > > > Only if older header files are used in combination with newer kernel > > > we would see the current behaviour. > > > > The code in question doesn't actually call mmap, it creates a syscall filter that tests whether any unknown flags are set. Basically > > if ((flags & ~known_flags) != 0) abort(); > > So putting something into known_flags that might not be known to the kernel when Emacs is run is harmless. In fact, it's beneficial for the case where the mman.h that's used when compiling seccomp-filter.c is older than the kernel that will be used to run Emacs. Werner -- "Having a smoking section in a restaurant is like having a peeing section in a swimming pool." -- Edward Burr