On Wed, Sep 19, 2018 at 2:50 AM Eric Biggers <ebiggers@xxxxxxxxxx> wrote: > Hardcoding the 'input' array to 600 bytes forces the full amount of space to be > reserved in the kernel image for every test vector. Also, if anyone adds a > longer test vector they will need to remember to increase the value. > > It should be a const pointer instead, like the test vectors in crypto/testmgr.h. I know. The agony. This has been really annoying me. I originally did it the right way, but removed it last week, when I noticed that gcc failed to put it in the initconst section: https://git.zx2c4.com/WireGuard/commit/?id=f4698d20f13946afc6ce99e98685ba3f9adc4474 Even changing the (u8[]){ ... } into a (const u8[]){ ... } or even into a const string literal does not do the trick. It makes it into the constant data section with const, but it does not make it into the initconst section. What a bummer. I went asking about this on the gcc mailing list, to see if there was just some aspect of C that I had overlooked: https://gcc.gnu.org/ml/gcc/2018-09/msg00043.html So far, it looks like we're SOL. I could probably make some macros to do this in a .S file but... that's pretty unacceptably gross. Or I could define lots and lots of variables in __initconst, and then connect them all together at the end, but that's pretty gross too. Or I could have all this data in one variable and record offsets into it, but that's even more atrocious. So I think it comes down to these two non-ugly options: - We use fixed sized buffers, waste a lot of space, and be happy that it's cleared from memory immediately after init/insertion anyway, so it's not actually wasting ram. - We use const string literals / constant compound literals, save space on disk, but not benefit from having it cleared from memory after init/insertion. Of these, which would you prefer? I can see the argument both ways, but in the end opted for the first. Or perhaps you have a better third option? Jason
