diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/kfunc_call_fail.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/kfunc_call_fail.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/kfunc_call_fail.c b/tools/testing/selftests/bpf/progs/kfunc_call_fail.c new file mode 100644 index 000000000000..b98313d391c6 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/kfunc_call_fail.c @@ -0,0 +1,160 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Facebook */ +#include <vmlinux.h> +#include <bpf/bpf_helpers.h> + +extern struct prog_test_ref_kfunc *bpf_kfunc_call_test_acquire(unsigned long *sp) __ksym; +extern void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym; +extern void bpf_kfunc_call_test_mem_len_pass1(void *mem, int len) __ksym; +extern int *bpf_kfunc_call_test_get_rdwr_mem(struct prog_test_ref_kfunc *p, const int rdwr_buf_size) __ksym; +extern int *bpf_kfunc_call_test_get_rdonly_mem(struct prog_test_ref_kfunc *p, const int rdonly_buf_size) __ksym; +extern int *bpf_kfunc_call_test_acq_rdonly_mem(struct prog_test_ref_kfunc *p, const int rdonly_buf_size) __ksym; +extern void bpf_kfunc_call_int_mem_release(int *p) __ksym; + +struct syscall_test_args { + __u8 data[16]; + size_t size; +}; + +SEC("?syscall") +int kfunc_syscall_test_fail(struct syscall_test_args *args) +{ + bpf_kfunc_call_test_mem_len_pass1(&args->data, sizeof(*args) + 1); + + return 0; +} + +SEC("?syscall") +int kfunc_syscall_test_null_fail(struct syscall_test_args *args) +{ + /* Must be called with args as a NULL pointer + * we do not check for it to have the verifier consider that + * the pointer might not be null, and so we can load it. + * + * So the following can not be added: + * + * if (args) + * return -22; + */ + + bpf_kfunc_call_test_mem_len_pass1(args, sizeof(*args)); + + return 0; +} + +SEC("?tc") +int kfunc_call_test_get_mem_fail_rdonly(struct __sk_buff *skb) +{ + struct prog_test_ref_kfunc *pt; + unsigned long s = 0; + int *p = NULL; + int ret = 0; + + pt = bpf_kfunc_call_test_acquire(&s); + if (pt) { + p = bpf_kfunc_call_test_get_rdonly_mem(pt, 2 * sizeof(int)); + if (p) + p[0] = 42; /* this is a read-only buffer, so -EACCES */ + else + ret = -1; + + bpf_kfunc_call_test_release(pt); + } + return ret; +} + +SEC("?tc") +int kfunc_call_test_get_mem_fail_use_after_free(struct __sk_buff *skb) +{ + struct prog_test_ref_kfunc *pt; + unsigned long s = 0; + int *p = NULL; + int ret = 0; + + pt = bpf_kfunc_call_test_acquire(&s); + if (pt) { + p = bpf_kfunc_call_test_get_rdwr_mem(pt, 2 * sizeof(int)); + if (p) { + p[0] = 42; + ret = p[1]; /* 108 */ + } else { + ret = -1; + } + + bpf_kfunc_call_test_release(pt); + } + if (p) + ret = p[0]; /* p is not valid anymore */ + + return ret; +} + +SEC("?tc") +int kfunc_call_test_get_mem_fail_oob(struct __sk_buff *skb) +{ + struct prog_test_ref_kfunc *pt; + unsigned long s = 0; + int *p = NULL; + int ret = 0; + + pt = bpf_kfunc_call_test_acquire(&s); + if (pt) { + p = bpf_kfunc_call_test_get_rdonly_mem(pt, 2 * sizeof(int)); + if (p) + ret = p[2 * sizeof(int)]; /* oob access, so -EACCES */ + else + ret = -1; + + bpf_kfunc_call_test_release(pt); + } + return ret; +} + +int not_const_size = 2 * sizeof(int); + +SEC("?tc") +int kfunc_call_test_get_mem_fail_not_const(struct __sk_buff *skb) +{ + struct prog_test_ref_kfunc *pt; + unsigned long s = 0; + int *p = NULL; + int ret = 0; + + pt = bpf_kfunc_call_test_acquire(&s); + if (pt) { + p = bpf_kfunc_call_test_get_rdonly_mem(pt, not_const_size); /* non const size, -EINVAL */ + if (p) + ret = p[0]; + else + ret = -1; + + bpf_kfunc_call_test_release(pt); + } + return ret; +} + +SEC("?tc") +int kfunc_call_test_mem_acquire_fail(struct __sk_buff *skb) +{ + struct prog_test_ref_kfunc *pt; + unsigned long s = 0; + int *p = NULL; + int ret = 0; + + pt = bpf_kfunc_call_test_acquire(&s); + if (pt) { + /* we are failing on this one, because we are not acquiring a PTR_TO_BTF_ID (a struct ptr) */ + p = bpf_kfunc_call_test_acq_rdonly_mem(pt, 2 * sizeof(int)); + if (p) + ret = p[0]; + else + ret = -1; + + bpf_kfunc_call_int_mem_release(p); + + bpf_kfunc_call_test_release(pt); + } + return ret; +} + +char _license[] SEC("license") = "GPL"; |