Re: [PATCH ima-evm-utils v4] Add tests for MMAP_CHECK and MMAP_CHECK_REQPROT hooks

From: Mimi Zohar
Date: Thu Feb 02 2023 - 15:40:47 EST


On Thu, 2023-02-02 at 17:23 +0100, Roberto Sassu wrote:
> > > + if (ptr == MAP_FAILED) {
> > > + ret = ERR_SETUP;
> > > + if (argv[2] && !strcmp(argv[2], "exec_on_writable") &&
> > > + errno == EACCES)
> > > + ret = ERR_TEST;
> > > +
> >
> > FYI, on an older distro kernel, the mmap fails and results in following
> > without any explanation.
> >
> > Test: check_mmap (hook="MMAP_CHECK", test_mmap arg: "exec")
> > Unexpected exit status 1 from test_mmap
> >
> > With some additional debugging, I'm seeing:
> > Failed mmap() /tmp/tmp.4gD2UjSvC4/tmp.PlzUEm09hO, err: -13 (Permission
> > denied)b
>
> Uhm, ok. Which kernel is failing?

I'm able to reproduce the error on a next-integrity or next-integrity-
testing kernel, by running the tests multiple times. The error doesn't
occur the first time running the test, but subsequent times.

Mimi