diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/preempt_lock.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/preempt_lock.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/preempt_lock.c b/tools/testing/selftests/bpf/progs/preempt_lock.c new file mode 100644 index 000000000000..7d04254e61f1 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/preempt_lock.c @@ -0,0 +1,212 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <vmlinux.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> +#include "bpf_misc.h" +#include "bpf_experimental.h" + +extern int bpf_copy_from_user_str(void *dst, u32 dst__sz, const void *unsafe_ptr__ign, u64 flags) __weak __ksym; + +SEC("?tc") +__failure __msg("BPF_EXIT instruction in main prog cannot be used inside bpf_preempt_disable-ed region") +int preempt_lock_missing_1(struct __sk_buff *ctx) +{ + bpf_preempt_disable(); + return 0; +} + +SEC("?tc") +__failure __msg("BPF_EXIT instruction in main prog cannot be used inside bpf_preempt_disable-ed region") +int preempt_lock_missing_2(struct __sk_buff *ctx) +{ + bpf_preempt_disable(); + bpf_preempt_disable(); + return 0; +} + +SEC("?tc") +__failure __msg("BPF_EXIT instruction in main prog cannot be used inside bpf_preempt_disable-ed region") +int preempt_lock_missing_3(struct __sk_buff *ctx) +{ + bpf_preempt_disable(); + bpf_preempt_disable(); + bpf_preempt_disable(); + return 0; +} + +SEC("?tc") +__failure __msg("BPF_EXIT instruction in main prog cannot be used inside bpf_preempt_disable-ed region") +int preempt_lock_missing_3_minus_2(struct __sk_buff *ctx) +{ + bpf_preempt_disable(); + bpf_preempt_disable(); + bpf_preempt_disable(); + bpf_preempt_enable(); + bpf_preempt_enable(); + return 0; +} + +static __noinline void preempt_disable(void) +{ + bpf_preempt_disable(); +} + +static __noinline void preempt_enable(void) +{ + bpf_preempt_enable(); +} + +SEC("?tc") +__failure __msg("BPF_EXIT instruction in main prog cannot be used inside bpf_preempt_disable-ed region") +int preempt_lock_missing_1_subprog(struct __sk_buff *ctx) +{ + preempt_disable(); + return 0; +} + +SEC("?tc") +__failure __msg("BPF_EXIT instruction in main prog cannot be used inside bpf_preempt_disable-ed region") +int preempt_lock_missing_2_subprog(struct __sk_buff *ctx) +{ + preempt_disable(); + preempt_disable(); + return 0; +} + +SEC("?tc") +__failure __msg("BPF_EXIT instruction in main prog cannot be used inside bpf_preempt_disable-ed region") +int preempt_lock_missing_2_minus_1_subprog(struct __sk_buff *ctx) +{ + preempt_disable(); + preempt_disable(); + preempt_enable(); + return 0; +} + +static __noinline void preempt_balance_subprog(void) +{ + preempt_disable(); + preempt_enable(); +} + +SEC("?tc") +__success int preempt_balance(struct __sk_buff *ctx) +{ + bpf_guard_preempt(); + return 0; +} + +SEC("?tc") +__success int preempt_balance_subprog_test(struct __sk_buff *ctx) +{ + preempt_balance_subprog(); + return 0; +} + +SEC("?fentry.s/" SYS_PREFIX "sys_getpgid") +__failure __msg("sleepable helper bpf_copy_from_user#") +int preempt_sleepable_helper(void *ctx) +{ + u32 data; + + bpf_preempt_disable(); + bpf_copy_from_user(&data, sizeof(data), NULL); + bpf_preempt_enable(); + return 0; +} + +SEC("?fentry.s/" SYS_PREFIX "sys_getpgid") +__failure __msg("kernel func bpf_copy_from_user_str is sleepable within non-preemptible region") +int preempt_sleepable_kfunc(void *ctx) +{ + u32 data; + + bpf_preempt_disable(); + bpf_copy_from_user_str(&data, sizeof(data), NULL, 0); + bpf_preempt_enable(); + return 0; +} + +int __noinline preempt_global_subprog(void) +{ + preempt_balance_subprog(); + return 0; +} + +SEC("?tc") +__success +int preempt_global_subprog_test(struct __sk_buff *ctx) +{ + preempt_disable(); + preempt_global_subprog(); + preempt_enable(); + return 0; +} + +int __noinline +global_subprog(int i) +{ + if (i) + bpf_printk("%p", &i); + return i; +} + +int __noinline +global_sleepable_helper_subprog(int i) +{ + if (i) + bpf_copy_from_user(&i, sizeof(i), NULL); + return i; +} + +int __noinline +global_sleepable_kfunc_subprog(int i) +{ + if (i) + bpf_copy_from_user_str(&i, sizeof(i), NULL, 0); + global_subprog(i); + return i; +} + +int __noinline +global_subprog_calling_sleepable_global(int i) +{ + if (!i) + global_sleepable_kfunc_subprog(i); + return i; +} + +SEC("?syscall") +__failure __msg("global functions that may sleep are not allowed in non-sleepable context") +int preempt_global_sleepable_helper_subprog(struct __sk_buff *ctx) +{ + preempt_disable(); + if (ctx->mark) + global_sleepable_helper_subprog(ctx->mark); + preempt_enable(); + return 0; +} + +SEC("?syscall") +__failure __msg("global functions that may sleep are not allowed in non-sleepable context") +int preempt_global_sleepable_kfunc_subprog(struct __sk_buff *ctx) +{ + preempt_disable(); + if (ctx->mark) + global_sleepable_kfunc_subprog(ctx->mark); + preempt_enable(); + return 0; +} + +SEC("?syscall") +__failure __msg("global functions that may sleep are not allowed in non-sleepable context") +int preempt_global_sleepable_subprog_indirect(struct __sk_buff *ctx) +{ + preempt_disable(); + if (ctx->mark) + global_subprog_calling_sleepable_global(ctx->mark); + preempt_enable(); + return 0; +} + +char _license[] SEC("license") = "GPL"; |