Hi, i wrote: > > > I will think about creating such an ISO by help of xorriso and dd.
Daniel Kiper wrote: > Yeah, that would be perfect... I believe to have created one. But grub-fstest does not produce a memory fault. See my mail Date: Tue, 29 Nov 2022 19:47:22 +0100 Message-Id: <50363882005823...@scdbackup.webframe.org> for the recipe to create that ISO. I riddle: - Would valgrind detect out-of-bounds reading in GRUB code ? (Or does the code under grub-fstest allocate a large memory chunk on which the memory management of GRUB operates ?) - Is there a way to build the involved code for use under gdb ? - How can i insert debug messages into grub-core/fs/iso9660.c ? > > > [more opportunities to let the code derail] > Huh! Could you fix these issues too? I will try. But first i need to master grub-fstest or some other testbed so that i can verify my theoretical considerations. (The "- 1" problem is obvious from C code considerations. But the number to replace the "1" is not so obvious and in general we should not fix what is not broken.) > > > In general: > > > How mistrusting should GRUB be towards the bytes in the filesystem ? > I think as little as possible. Especially if incorrect values may lead > to OOB writes... It is about out-of-bounds reads. But i don't understand well the combination of your two sentences: GRUB shall be credulent, especially if bad writes were involved ? I would think that this is to be avoided most. So please explain the philosopy a bit more verbous for an old programmer or point me to examples. (I would look into the other fs drivers if i would understand filesystems other than ISO 9660.) Have a nice day :) Thomas _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
