31 lines
627 B
C
31 lines
627 B
C
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// SPDX-License-Identifier: GPL-2.0
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#include <linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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#include <errno.h>
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#include <linux/capability.h>
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typedef struct { unsigned long long val; } kernel_cap_t;
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struct cred {
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kernel_cap_t cap_effective;
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} __attribute__((preserve_access_index));
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char _license[] SEC("license") = "GPL";
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SEC("lsm.s/userns_create")
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int BPF_PROG(test_userns_create, const struct cred *cred, int ret)
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{
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kernel_cap_t caps = cred->cap_effective;
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__u64 cap_mask = 1ULL << CAP_SYS_ADMIN;
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if (ret)
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return 0;
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ret = -EPERM;
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if (caps.val & cap_mask)
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return 0;
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return -EPERM;
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}
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