On Mon, 2018-12-17 at 11:06 -0800, Linus Torvalds wrote: > On Mon, Dec 17, 2018 at 10:49 AM Linus Torvalds > <torva...@linux-foundation.org> wrote: > > > > So the *simplest* fix would seem to be to literally remove all those > > "= -1" for the Opt_err initialization. Making the code smaller, > > simpler, and fixing the bug in the process. > > Something like this > > git grep -l 'Opt_err = -1' | xargs sed -i 's/Opt_err = -1/Opt_err/' > > would do it, but I also notice that > security/integrity/ima/ima_policy.c then has some truly funky code > that plays around with the enum numbers , ie > > #define pt(token) policy_tokens[token + Opt_err].pattern
Yikes! > which actually depends on the ordering of policy_tokens[], and depends > on the exact values, ie it literally (and quite insanely) sets Opt_err > to -1, and then Opt_measure to 1, and leaves 0 unused. That code > seriously makes no sense at all, and is fundamentally broken. > > It would be better to use > > #define pt(token) policy_tokens[token - Opt_measure].pattern > > instead, but even then you should have a huge comment about how the > policy_tokens[] array absolutely has to be properly ordered. Will do. > > Honestly, for being about "security", all of this code seems to be > doing some really questionable things with all those Opt_xyz enums. It's being used for parsing and displaying the policy, which do need to be in sync. Mimi
