diff options
Diffstat (limited to '')
-rw-r--r-- | tools/testing/selftests/bpf/progs/test_core_autosize.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_core_autosize.c b/tools/testing/selftests/bpf/progs/test_core_autosize.c new file mode 100644 index 000000000..9a7829c5e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_autosize.c @@ -0,0 +1,182 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ + +#include <linux/bpf.h> +#include <stdint.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_core_read.h> + +char _license[] SEC("license") = "GPL"; + +/* fields of exactly the same size */ +struct test_struct___samesize { + void *ptr; + unsigned long long val1; + unsigned int val2; + unsigned short val3; + unsigned char val4; +} __attribute((preserve_access_index)); + +/* unsigned fields that have to be downsized by libbpf */ +struct test_struct___downsize { + void *ptr; + unsigned long val1; + unsigned long val2; + unsigned long val3; + unsigned long val4; + /* total sz: 40 */ +} __attribute__((preserve_access_index)); + +/* fields with signed integers of wrong size, should be rejected */ +struct test_struct___signed { + void *ptr; + long val1; + long val2; + long val3; + long val4; +} __attribute((preserve_access_index)); + +/* real layout and sizes according to test's (32-bit) BTF */ +struct test_struct___real { + unsigned int ptr; /* can't use `void *`, it is always 8 byte in BPF target */ + unsigned int val2; + unsigned long long val1; + unsigned short val3; + unsigned char val4; + unsigned char _pad; + /* total sz: 20 */ +}; + +struct test_struct___real input = { + .ptr = 0x01020304, + .val1 = 0x1020304050607080, + .val2 = 0x0a0b0c0d, + .val3 = 0xfeed, + .val4 = 0xb9, + ._pad = 0xff, /* make sure no accidental zeros are present */ +}; + +unsigned long long ptr_samesized = 0; +unsigned long long val1_samesized = 0; +unsigned long long val2_samesized = 0; +unsigned long long val3_samesized = 0; +unsigned long long val4_samesized = 0; +struct test_struct___real output_samesized = {}; + +unsigned long long ptr_downsized = 0; +unsigned long long val1_downsized = 0; +unsigned long long val2_downsized = 0; +unsigned long long val3_downsized = 0; +unsigned long long val4_downsized = 0; +struct test_struct___real output_downsized = {}; + +unsigned long long ptr_probed = 0; +unsigned long long val1_probed = 0; +unsigned long long val2_probed = 0; +unsigned long long val3_probed = 0; +unsigned long long val4_probed = 0; + +unsigned long long ptr_signed = 0; +unsigned long long val1_signed = 0; +unsigned long long val2_signed = 0; +unsigned long long val3_signed = 0; +unsigned long long val4_signed = 0; +struct test_struct___real output_signed = {}; + +SEC("raw_tp/sys_exit") +int handle_samesize(void *ctx) +{ + struct test_struct___samesize *in = (void *)&input; + struct test_struct___samesize *out = (void *)&output_samesized; + + ptr_samesized = (unsigned long long)in->ptr; + val1_samesized = in->val1; + val2_samesized = in->val2; + val3_samesized = in->val3; + val4_samesized = in->val4; + + out->ptr = in->ptr; + out->val1 = in->val1; + out->val2 = in->val2; + out->val3 = in->val3; + out->val4 = in->val4; + + return 0; +} + +SEC("raw_tp/sys_exit") +int handle_downsize(void *ctx) +{ + struct test_struct___downsize *in = (void *)&input; + struct test_struct___downsize *out = (void *)&output_downsized; + + ptr_downsized = (unsigned long long)in->ptr; + val1_downsized = in->val1; + val2_downsized = in->val2; + val3_downsized = in->val3; + val4_downsized = in->val4; + + out->ptr = in->ptr; + out->val1 = in->val1; + out->val2 = in->val2; + out->val3 = in->val3; + out->val4 = in->val4; + + return 0; +} + +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ +#define bpf_core_read_int bpf_core_read +#else +#define bpf_core_read_int(dst, sz, src) ({ \ + /* Prevent "subtraction from stack pointer prohibited" */ \ + volatile long __off = sizeof(*dst) - (sz); \ + bpf_core_read((char *)(dst) + __off, sz, src); \ +}) +#endif + +SEC("raw_tp/sys_enter") +int handle_probed(void *ctx) +{ + struct test_struct___downsize *in = (void *)&input; + __u64 tmp; + + tmp = 0; + bpf_core_read_int(&tmp, bpf_core_field_size(in->ptr), &in->ptr); + ptr_probed = tmp; + + tmp = 0; + bpf_core_read_int(&tmp, bpf_core_field_size(in->val1), &in->val1); + val1_probed = tmp; + + tmp = 0; + bpf_core_read_int(&tmp, bpf_core_field_size(in->val2), &in->val2); + val2_probed = tmp; + + tmp = 0; + bpf_core_read_int(&tmp, bpf_core_field_size(in->val3), &in->val3); + val3_probed = tmp; + + tmp = 0; + bpf_core_read_int(&tmp, bpf_core_field_size(in->val4), &in->val4); + val4_probed = tmp; + + return 0; +} + +SEC("raw_tp/sys_enter") +int handle_signed(void *ctx) +{ + struct test_struct___signed *in = (void *)&input; + struct test_struct___signed *out = (void *)&output_signed; + + val2_signed = in->val2; + val3_signed = in->val3; + val4_signed = in->val4; + + out->val2= in->val2; + out->val3= in->val3; + out->val4= in->val4; + + return 0; +} |