Add a focused regression test for a sandboxed PTY master holder using
TIOCSIG to signal an out-of-domain slave foreground process group.
The test observes both the ioctl result and the target's signal-handler
effect. It fails on the unpatched base because TIOCSIG succeeds and
SIGTSTP is delivered. It passes with the preceding RFC prototype because
the ioctl fails with EPERM and the target observes no signal.
The identical test binary and initramfs were booted against both kernels
under QEMU. TAP reported one failing test on the affected image and one
passing test on the patched image.
Assisted-by: Claude:claude-opus-4-8
Assisted-by: Codex:gpt-5.6-sol
Signed-off-by: Christopher Lusk <redacted>
Sashiko has reviewed this patch and found no issues. It looks great!
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Sashiko AI review · https://sashiko.dev/#/patchset/20260913221958.839429-1-clusk@northecho.dev?part=2