1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <vmlinux.h> 4 #include <bpf/bpf_helpers.h> 5 #include "bpf_misc.h" 6 7 void *user_ptr; 8 char dynptr_buf[8]; 9 u64 kaddr; 10 11 extern struct kmem_cache *bpf_get_kmem_cache(u64 addr) __ksym; 12 13 SEC("socket") 14 __success 15 __caps_unpriv(CAP_BPF) 16 __failure_unpriv 17 __msg_unpriv("bpf_rdonly_cast is allowed only to CAP_PERFMON and CAP_SYS_ADMIN") 18 int rdonly_cast_noperfmon(void *ctx) 19 { 20 char *p = bpf_rdonly_cast(0, 0); 21 22 return p[0x7fff]; 23 } 24 25 SEC("socket") 26 __success 27 __caps_unpriv(CAP_BPF) 28 __failure_unpriv 29 __msg_unpriv("bpf_probe_read_kernel_dynptr is allowed only to CAP_PERFMON and CAP_SYS_ADMIN") 30 int probe_read_kernel_dynptr_noperfmon(void *ctx) 31 { 32 struct bpf_dynptr dptr; 33 34 bpf_dynptr_from_mem(dynptr_buf, sizeof(dynptr_buf), 0, &dptr); 35 bpf_probe_read_kernel_dynptr(&dptr, 0, sizeof(dynptr_buf), user_ptr); 36 return 0; 37 } 38 39 SEC("socket") 40 __success 41 __caps_unpriv(CAP_BPF) 42 __failure_unpriv 43 __msg_unpriv("bpf_stream_vprintk is allowed only to CAP_PERFMON and CAP_SYS_ADMIN") 44 int stream_vprintk_noperfmon(void *ctx) 45 { 46 bpf_stream_printk(BPF_STDOUT, "%pB", (void *)kaddr); 47 return 0; 48 } 49 50 SEC("socket") 51 __success 52 __caps_unpriv(CAP_BPF) 53 __failure_unpriv 54 __msg_unpriv("bpf_get_kmem_cache is allowed only to CAP_PERFMON and CAP_SYS_ADMIN") 55 int get_kmem_cache_noperfmon(void *ctx) 56 { 57 return !!bpf_get_kmem_cache(kaddr); 58 } 59 60 __weak int subprog_untrusted_read(void *p __arg_untrusted) 61 { 62 return *(char *)p; 63 } 64 65 SEC("socket") 66 __success 67 __caps_unpriv(CAP_BPF) 68 __failure_unpriv 69 __msg_unpriv("rdonly_untrusted_mem access is allowed only to CAP_PERFMON and CAP_SYS_ADMIN") 70 int arg_untrusted_read_noperfmon(void *ctx) 71 { 72 return subprog_untrusted_read(0); 73 } 74 75 char _license[] SEC("license") = "GPL"; 76