tools/testing/selftests/bpf/progs/test_deny_namespace.c

File Facts

System

Linux kernel

Corpus path

tools/testing/selftests/bpf/progs/test_deny_namespace.c

Extension

.c

Size

627 bytes

Lines

31

Domain

Support Tooling And Documentation

Bucket

tools

Inferred role

Support Tooling And Documentation: implementation source

Status

source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

• Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/bpf.h
• bpf/bpf_helpers.h
• bpf/bpf_tracing.h
• errno.h
• linux/capability.h

Detected Declarations

• struct cred
• function BPF_PROG

Annotated Snippet

struct cred {
	kernel_cap_t cap_effective;
} __attribute__((preserve_access_index));

char _license[] SEC("license") = "GPL";

SEC("lsm.s/userns_create")
int BPF_PROG(test_userns_create, const struct cred *cred, int ret)
{
	kernel_cap_t caps = cred->cap_effective;
	__u64 cap_mask = 1ULL << CAP_SYS_ADMIN;

	if (ret)
		return 0;

	ret = -EPERM;
	if (caps.val & cap_mask)
		return 0;

	return -EPERM;
}

Annotation

• Immediate include surface: `linux/bpf.h`, `bpf/bpf_helpers.h`, `bpf/bpf_tracing.h`, `errno.h`, `linux/capability.h`.
• Detected declarations: `struct cred`, `function BPF_PROG`.
• Atlas domain: Support Tooling And Documentation / tools.
• Implementation status: source implementation candidate.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.