This change takes capsicum-test from upstream and applies some local changes to make the
tests work on FreeBSD when executed via Kyua.
The local modifications are as follows:
1. Make `OpenatTest.WithFlag` pass with the new dot-dot lookup behavior in FreeBSD 12.x+.
2. capsicum-test references a set of helper binaries: `mini-me`, `mini-me.noexec`, and
`mini-me.setuid`, as part of the execve/fexecve tests, via execve, fexecve, and open.
It achieves this upstream by assuming `mini-me*` is in the current directory, however,
in order for Kyua to execute `capsicum-test`, it needs to provide a full path to
`mini-me*`. In order to achieve this, I made `capsicum-test` cache the executable's
path from argv[0] in main(..) and use the cached value to compute the path to
`mini-me*` as part of the execve/fexecve testcases.
3. The capsicum-test test suite assumes that it's always being run on CAPABILITIES enabled
kernels. However, there's a chance that the test will be run on a host without a
CAPABILITIES enabled kernel, so we must check for the support before running the tests.
The way to achieve this is to add the relevant `feature_present("security_capabilities")`
check to SetupEnvironment::SetUp() and skip the tests when the support is not available.
While here, add a check for `kern.trap_enotcap` being enabled. As noted by markj@ in
https://github.com/google/capsicum-test/issues/23, this sysctl being enabled can trigger
non-deterministic failures. Therefore, the tests should be skipped if this sysctl is
enabled.
All local changes have been submitted to the capsicum-test project
(https://github.com/google/capsicum-test) and are in various stages of review.
Please see the following pull requests for more details:
1. https://github.com/google/capsicum-test/pull/35
2. https://github.com/google/capsicum-test/pull/41
3. https://github.com/google/capsicum-test/pull/42
Reviewed by: asomers
Discussed with: emaste, markj
Approved by: emaste (mentor)
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D19758
Previously it was possible to connect a socket (which had the
CAP_CONNECT right) by calling "connectat(AT_FDCWD, ...)" even in
capabilties mode. This combination should be treated the same as a call
to connect (i.e. forbidden in capabilities mode). Similarly for bindat.
Disable connectat/bindat with AT_FDCWD in capabilities mode, fix up the
documentation and add tests.
PR: 222632
Submitted by: Jan Kokemüller <jan.kokemueller@gmail.com>
Reviewed by: Domagoj Stolfa
MFC after: 1 week
Relnotes: Yes
Differential Revision: https://reviews.freebsd.org/D15221
fget_cap() tries to do a cheaper snapshot of a file descriptor without
holding the file descriptor lock. This snapshot does not do a deep
copy of the ioctls capability array, but instead uses a different
return value to inform the caller to retry the copy with the lock
held. However, filecaps_copy() was returning 1 to indicate that a
retry was required, and fget_cap() was checking for 0 (actually
'!filecaps_copy()'). As a result, fget_cap() did not do a deep copy
of the ioctls array and just reused the original pointer. This cause
multiple file descriptor entries to think they owned the same pointer
and eventually resulted in duplicate frees.
The only code path that I'm aware of that triggers this is to create a
listen socket that has a restricted list of ioctls and then call
accept() which calls fget_cap() with a valid filecaps structure from
getsock_cap().
To fix, change the return value of filecaps_copy() to return true if
it succeeds in copying the caps and false if it fails because the lock
is required. I find this more intuitive than fixing the caller in
this case. While here, change the return type from 'int' to 'bool'.
Finally, make filecaps_copy() more robust in the failure case by not
copying any of the source filecaps structure over. This avoids the
possibility of leaking a pointer into a structure if a similar future
caller doesn't properly handle the return value from filecaps_copy()
at the expense of one more branch.
I also added a test case that panics before this change and now passes.
Reviewed by: kib
Discussed with: mjg (not a fan of the extra branch)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D15047
