From: Feng Yang <[email protected]> if it works under NMI and doesn't use any context-dependent things, should be fine for any program type. The detailed discussion is in [1].
[1] https://lore.kernel.org/all/caef4bza6gk3dsrtosk6k3ozgthesndsrdd8sdeq-gis6oji...@mail.gmail.com/ Suggested-by: Andrii Nakryiko <[email protected]> Signed-off-by: Feng Yang <[email protected]> --- Changes in v2: - not expose compat probe read APIs to more program types. - Remove the prog->sleepable check added for copy_from_user, - or the summarization_freplace/might_sleep_with_might_sleep test will fail with the error "program of this type cannot use helper bpf_copy_from_user" - Link to v1: https://lore.kernel.org/all/[email protected]/ --- kernel/bpf/cgroup.c | 6 ------ kernel/bpf/helpers.c | 38 +++++++++++++++++++++++++++++++++++++ kernel/trace/bpf_trace.c | 41 ++++------------------------------------ net/core/filter.c | 2 -- 4 files changed, 42 insertions(+), 45 deletions(-) diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 84f58f3d028a..dbdad5f42761 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -2607,16 +2607,10 @@ const struct bpf_func_proto * cgroup_current_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { - case BPF_FUNC_get_current_uid_gid: - return &bpf_get_current_uid_gid_proto; - case BPF_FUNC_get_current_comm: - return &bpf_get_current_comm_proto; #ifdef CONFIG_CGROUP_NET_CLASSID case BPF_FUNC_get_cgroup_classid: return &bpf_get_cgroup_classid_curr_proto; #endif - case BPF_FUNC_current_task_under_cgroup: - return &bpf_current_task_under_cgroup_proto; default: return NULL; } diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index e3a2662f4e33..a01a2e55e17d 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -23,6 +23,7 @@ #include <linux/btf_ids.h> #include <linux/bpf_mem_alloc.h> #include <linux/kasan.h> +#include <linux/bpf_verifier.h> #include "../../lib/kstrtox.h" @@ -1912,6 +1913,12 @@ const struct bpf_func_proto bpf_probe_read_user_str_proto __weak; const struct bpf_func_proto bpf_probe_read_kernel_proto __weak; const struct bpf_func_proto bpf_probe_read_kernel_str_proto __weak; const struct bpf_func_proto bpf_task_pt_regs_proto __weak; +const struct bpf_func_proto bpf_perf_event_read_proto __weak; +const struct bpf_func_proto bpf_send_signal_proto __weak; +const struct bpf_func_proto bpf_send_signal_thread_proto __weak; +const struct bpf_func_proto bpf_get_task_stack_sleepable_proto __weak; +const struct bpf_func_proto bpf_get_task_stack_proto __weak; +const struct bpf_func_proto bpf_get_branch_snapshot_proto __weak; const struct bpf_func_proto * bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) @@ -1965,6 +1972,8 @@ bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_current_pid_tgid_proto; case BPF_FUNC_get_ns_current_pid_tgid: return &bpf_get_ns_current_pid_tgid_proto; + case BPF_FUNC_get_current_uid_gid: + return &bpf_get_current_uid_gid_proto; default: break; } @@ -2022,6 +2031,8 @@ bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_current_cgroup_id_proto; case BPF_FUNC_get_current_ancestor_cgroup_id: return &bpf_get_current_ancestor_cgroup_id_proto; + case BPF_FUNC_current_task_under_cgroup: + return &bpf_current_task_under_cgroup_proto; #endif default: break; @@ -2037,6 +2048,8 @@ bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_current_task_proto; case BPF_FUNC_get_current_task_btf: return &bpf_get_current_task_btf_proto; + case BPF_FUNC_get_current_comm: + return &bpf_get_current_comm_proto; case BPF_FUNC_probe_read_user: return &bpf_probe_read_user_proto; case BPF_FUNC_probe_read_kernel: @@ -2047,6 +2060,10 @@ bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_probe_read_kernel_str: return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ? NULL : &bpf_probe_read_kernel_str_proto; + case BPF_FUNC_copy_from_user: + return &bpf_copy_from_user_proto; + case BPF_FUNC_copy_from_user_task: + return &bpf_copy_from_user_task_proto; case BPF_FUNC_snprintf_btf: return &bpf_snprintf_btf_proto; case BPF_FUNC_snprintf: @@ -2057,6 +2074,27 @@ bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return bpf_get_trace_vprintk_proto(); case BPF_FUNC_perf_event_read_value: return bpf_get_perf_event_read_value_proto(); + case BPF_FUNC_perf_event_read: + return &bpf_perf_event_read_proto; + case BPF_FUNC_send_signal: + return &bpf_send_signal_proto; + case BPF_FUNC_send_signal_thread: + return &bpf_send_signal_thread_proto; + case BPF_FUNC_get_task_stack: + return prog->sleepable ? &bpf_get_task_stack_sleepable_proto + : &bpf_get_task_stack_proto; + case BPF_FUNC_task_storage_get: + if (bpf_prog_check_recur(prog)) + return &bpf_task_storage_get_recur_proto; + return &bpf_task_storage_get_proto; + case BPF_FUNC_task_storage_delete: + if (bpf_prog_check_recur(prog)) + return &bpf_task_storage_delete_recur_proto; + return &bpf_task_storage_delete_proto; + case BPF_FUNC_get_branch_snapshot: + return &bpf_get_branch_snapshot_proto; + case BPF_FUNC_find_vma: + return &bpf_find_vma_proto; default: return NULL; } diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 52c432a44aeb..868920994517 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -572,7 +572,7 @@ BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags) return value; } -static const struct bpf_func_proto bpf_perf_event_read_proto = { +const struct bpf_func_proto bpf_perf_event_read_proto = { .func = bpf_perf_event_read, .gpl_only = true, .ret_type = RET_INTEGER, @@ -882,7 +882,7 @@ BPF_CALL_1(bpf_send_signal, u32, sig) return bpf_send_signal_common(sig, PIDTYPE_TGID, NULL, 0); } -static const struct bpf_func_proto bpf_send_signal_proto = { +const struct bpf_func_proto bpf_send_signal_proto = { .func = bpf_send_signal, .gpl_only = false, .ret_type = RET_INTEGER, @@ -894,7 +894,7 @@ BPF_CALL_1(bpf_send_signal_thread, u32, sig) return bpf_send_signal_common(sig, PIDTYPE_PID, NULL, 0); } -static const struct bpf_func_proto bpf_send_signal_thread_proto = { +const struct bpf_func_proto bpf_send_signal_thread_proto = { .func = bpf_send_signal_thread, .gpl_only = false, .ret_type = RET_INTEGER, @@ -1185,7 +1185,7 @@ BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags) return entry_cnt * br_entry_size; } -static const struct bpf_func_proto bpf_get_branch_snapshot_proto = { +const struct bpf_func_proto bpf_get_branch_snapshot_proto = { .func = bpf_get_branch_snapshot, .gpl_only = true, .ret_type = RET_INTEGER, @@ -1430,14 +1430,8 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) const struct bpf_func_proto *func_proto; switch (func_id) { - case BPF_FUNC_get_current_uid_gid: - return &bpf_get_current_uid_gid_proto; - case BPF_FUNC_get_current_comm: - return &bpf_get_current_comm_proto; case BPF_FUNC_get_smp_processor_id: return &bpf_get_smp_processor_id_proto; - case BPF_FUNC_perf_event_read: - return &bpf_perf_event_read_proto; #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE case BPF_FUNC_probe_read: return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ? @@ -1446,35 +1440,8 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ? NULL : &bpf_probe_read_compat_str_proto; #endif -#ifdef CONFIG_CGROUPS - case BPF_FUNC_current_task_under_cgroup: - return &bpf_current_task_under_cgroup_proto; -#endif - case BPF_FUNC_send_signal: - return &bpf_send_signal_proto; - case BPF_FUNC_send_signal_thread: - return &bpf_send_signal_thread_proto; - case BPF_FUNC_get_task_stack: - return prog->sleepable ? &bpf_get_task_stack_sleepable_proto - : &bpf_get_task_stack_proto; - case BPF_FUNC_copy_from_user: - return &bpf_copy_from_user_proto; - case BPF_FUNC_copy_from_user_task: - return &bpf_copy_from_user_task_proto; - case BPF_FUNC_task_storage_get: - if (bpf_prog_check_recur(prog)) - return &bpf_task_storage_get_recur_proto; - return &bpf_task_storage_get_proto; - case BPF_FUNC_task_storage_delete: - if (bpf_prog_check_recur(prog)) - return &bpf_task_storage_delete_recur_proto; - return &bpf_task_storage_delete_proto; case BPF_FUNC_get_func_ip: return &bpf_get_func_ip_proto_tracing; - case BPF_FUNC_get_branch_snapshot: - return &bpf_get_branch_snapshot_proto; - case BPF_FUNC_find_vma: - return &bpf_find_vma_proto; default: break; } diff --git a/net/core/filter.c b/net/core/filter.c index 79cab4d78dc3..53bf560354f7 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8488,8 +8488,6 @@ sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_msg_pop_data_proto; case BPF_FUNC_perf_event_output: return &bpf_event_output_data_proto; - case BPF_FUNC_get_current_uid_gid: - return &bpf_get_current_uid_gid_proto; case BPF_FUNC_sk_storage_get: return &bpf_sk_storage_get_proto; case BPF_FUNC_sk_storage_delete: -- 2.43.0
