Commit graph

6 commits

Author SHA1 Message Date
Justine Tunney
5546559034 Improve pledge() usability and consistency
- We now kill the program on violations like OpenBSD
- We now print a message explaining which promise is needed
- This change also fixes a linkage bug with thread local storage
- Your sigaction() handlers should now be more thread safe

A new `__pledge_mode` global has been introduced to make pledge() more
customizable on Linux. For example:

    __attribute__((__constructor__)) static void init(void) {
      __pledge_mode = SECCOMP_RET_ERRNO | EPERM;
    }

Can be used to restore our old permissive pledge() behavior.
2022-08-07 16:18:33 -07:00
Justine Tunney
a8cf0f7e89 Add more missing libc functionality 2022-08-06 10:50:51 -07:00
Justine Tunney
cf93ecbbb2 Prove that Makefile is fully defined
The whole repository is now buildable with GNU Make Landlock sandboxing.
This proves that no Makefile targets exist which touch files other than
their declared prerequisites. In order to do this, we had to:

  1. Stop code morphing GCC output in package.com and instead run a
     newly introduced FIXUPOBJ.COM command after GCC invocations.

  2. Disable all the crumby Python unit tests that do things like create
     files in the current directory, or rename() files between folders.
     This ended up being a lot of tests, but most of them are still ok.

  3. Introduce an .UNSANDBOXED variable to GNU Make to disable Landlock.
     We currently only do this for things like `make tags`.

  4. This change deletes some GNU Make code that was preventing the
     execve() optimization from working. This means it should no longer
     be necessary in most cases for command invocations to be indirected
     through the cocmd interpreter.

  5. Missing dependencies had to be declared in certain places, in cases
     where they couldn't be automatically determined by MKDEPS.COM

  6. The libcxx header situation has finally been tamed. One of the
     things that makes this difficult is MKDEPS.COM only wants to
     consider the first 64kb of a file, in order to go fast. But libcxx
     likes to have #include lines buried after huge documentation.

  7. An .UNVEIL variable has been introduced to GNU Make just in case
     we ever wish to explicitly specify additional things that need to
     be whitelisted which aren't strictly prerequisites. This works in
     a manner similar to the recently introduced .EXTRA_PREREQS feature.

There's now a new build/bootstrap/make.com prebuilt binary available. It
should no longer be possible to write invalid Makefile code.
2022-08-06 04:05:08 -07:00
Justine Tunney
e98514cdb7 Plug a hole in pledge()
Günther Noack points out that O_RDONLY|O_TRUNC will modify a file.
2022-07-24 23:41:59 -07:00
Justine Tunney
3443039f34 Perform code cleanup on test pledges 2022-07-24 22:34:13 -07:00
Justine Tunney
3d2cf95af1 Remove malloc() dependency on pledge() / unveil()
This change also fixes a bug with gettid() being incorrect after fork().
We now implement the ENOENT behavior for getauxval(). The getuid() etc.
system calls are now faster too. Plus issetugid() will work on BSDs.
2022-07-24 21:51:37 -07:00
Renamed from test/libc/mem/unveil_test.c (Browse further)