1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ 3 4 #include "vmlinux.h" 5 #include <bpf/bpf_helpers.h> 6 #include <bpf/bpf_tracing.h> 7 8 char _license[] SEC("license") = "GPL"; 9 10 /* rodata section */ 11 const volatile pid_t pid; 12 const volatile size_t bss_array_len; 13 const volatile size_t data_array_len; 14 15 /* bss section */ 16 int sum = 0; 17 int array[1]; 18 19 /* custom data section */ 20 int my_array[1] SEC(".data.custom"); 21 22 /* custom data section which should NOT be resizable, 23 * since it contains a single var which is not an array 24 */ 25 int my_int SEC(".data.non_array"); 26 27 /* custom data section which should NOT be resizable, 28 * since its last var is not an array 29 */ 30 int my_array_first[1] SEC(".data.array_not_last"); 31 int my_int_last SEC(".data.array_not_last"); 32 33 int percpu_arr[1] SEC(".data.percpu_arr"); 34 35 /* at least one extern is included, to ensure that a specific 36 * regression is tested whereby resizing resulted in a free-after-use 37 * bug after type information is invalidated by the resize operation. 38 * 39 * There isn't a particularly good API to test for this specific condition, 40 * but by having externs for the resizing tests it will cover this path. 41 */ 42 extern int LINUX_KERNEL_VERSION __kconfig; 43 long version_sink; 44 45 SEC("tp/syscalls/sys_enter_getpid") bss_array_sum(void * ctx)46int bss_array_sum(void *ctx) 47 { 48 if (pid != (bpf_get_current_pid_tgid() >> 32)) 49 return 0; 50 51 /* this will be zero, we just rely on verifier not rejecting this */ 52 sum = percpu_arr[bpf_get_smp_processor_id()]; 53 54 for (size_t i = 0; i < bss_array_len; ++i) 55 sum += array[i]; 56 57 /* see above; ensure this is not optimized out */ 58 version_sink = LINUX_KERNEL_VERSION; 59 60 return 0; 61 } 62 63 SEC("tp/syscalls/sys_enter_getuid") data_array_sum(void * ctx)64int data_array_sum(void *ctx) 65 { 66 if (pid != (bpf_get_current_pid_tgid() >> 32)) 67 return 0; 68 69 /* this will be zero, we just rely on verifier not rejecting this */ 70 sum = percpu_arr[bpf_get_smp_processor_id()]; 71 72 for (size_t i = 0; i < data_array_len; ++i) 73 sum += my_array[i]; 74 75 /* see above; ensure this is not optimized out */ 76 version_sink = LINUX_KERNEL_VERSION; 77 78 return 0; 79 } 80 81 SEC("struct_ops/test_1") BPF_PROG(test_1)82int BPF_PROG(test_1) 83 { 84 return 0; 85 } 86 87 struct bpf_testmod_ops { 88 int (*test_1)(void); 89 }; 90 91 SEC(".struct_ops.link") 92 struct bpf_testmod_ops st_ops_resize = { 93 .test_1 = (void *)test_1 94 }; 95