bpf: Added new helper bpf_get_ns_current_pid_tgid (b4490c5c) · Commits · 戴 / test

include/linux/bpf.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -1497,6 +1497,7 @@ extern const struct bpf_func_proto bpf_strtol_proto;
		extern const struct bpf_func_proto bpf_strtoul_proto;
		extern const struct bpf_func_proto bpf_tcp_sock_proto;
		extern const struct bpf_func_proto bpf_jiffies64_proto;
		extern const struct bpf_func_proto bpf_get_ns_current_pid_tgid_proto;

		/* Shared helpers among cBPF and eBPF. */
		void bpf_user_rnd_init_once(void);

+19 −1

Original line number	Diff line number	Diff line
		@@ -2914,6 +2914,19 @@ union bpf_attr {
		* of sizeof(struct perf_branch_entry).
		*
		* -ENOENT if architecture does not support branch records.
		*
		* int bpf_get_ns_current_pid_tgid(u64 dev, u64 ino, struct bpf_pidns_info *nsdata, u32 size)
		* Description
		* Returns 0 on success, values for pid and tgid as seen from the current
		* namespace will be returned in nsdata.
		*
		* On failure, the returned value is one of the following:
		*
		* -EINVAL if dev and inum supplied don't match dev_t and inode number
		* with nsfs of current task, or if dev conversion to dev_t lost high bits.
		*
		* -ENOENT if pidns does not exists for the current task.
		*
		*/
		#define __BPF_FUNC_MAPPER(FN) \
		FN(unspec), \
		@@ -3035,7 +3048,8 @@ union bpf_attr {
		FN(tcp_send_ack), \
		FN(send_signal_thread), \
		FN(jiffies64), \
		FN(read_branch_records),
		FN(read_branch_records), \
		FN(get_ns_current_pid_tgid),

		/* integer value in 'imm' field of BPF_CALL instruction selects which helper
		* function eBPF program intends to call
		@@ -3829,4 +3843,8 @@ struct bpf_sockopt {
		__s32 retval;
		};

		struct bpf_pidns_info {
		__u32 pid;
		__u32 tgid;
		};
		#endif /* _UAPI__LINUX_BPF_H__ */

+1 −0

Original line number	Diff line number	Diff line
		@@ -2149,6 +2149,7 @@ const struct bpf_func_proto bpf_get_current_uid_gid_proto __weak;
		const struct bpf_func_proto bpf_get_current_comm_proto __weak;
		const struct bpf_func_proto bpf_get_current_cgroup_id_proto __weak;
		const struct bpf_func_proto bpf_get_local_storage_proto __weak;
		const struct bpf_func_proto bpf_get_ns_current_pid_tgid_proto __weak;

		const struct bpf_func_proto * __weak bpf_get_trace_printk_proto(void)
		{

+45 −0

Original line number	Diff line number	Diff line
		@@ -12,6 +12,8 @@
		#include <linux/filter.h>
		#include <linux/ctype.h>
		#include <linux/jiffies.h>
		#include <linux/pid_namespace.h>
		#include <linux/proc_ns.h>

		#include "../../lib/kstrtox.h"

		@@ -499,3 +501,46 @@ const struct bpf_func_proto bpf_strtoul_proto = {
		.arg4_type = ARG_PTR_TO_LONG,
		};
		#endif

		BPF_CALL_4(bpf_get_ns_current_pid_tgid, u64, dev, u64, ino,
		struct bpf_pidns_info *, nsdata, u32, size)
		{
		struct task_struct *task = current;
		struct pid_namespace *pidns;
		int err = -EINVAL;

		if (unlikely(size != sizeof(struct bpf_pidns_info)))
		goto clear;

		if (unlikely((u64)(dev_t)dev != dev))
		goto clear;

		if (unlikely(!task))
		goto clear;

		pidns = task_active_pid_ns(task);
		if (unlikely(!pidns)) {
		err = -ENOENT;
		goto clear;
		}

		if (!ns_match(&pidns->ns, (dev_t)dev, ino))
		goto clear;

		nsdata->pid = task_pid_nr_ns(task, pidns);
		nsdata->tgid = task_tgid_nr_ns(task, pidns);
		return 0;
		clear:
		memset((void *)nsdata, 0, (size_t) size);
		return err;
		}

		const struct bpf_func_proto bpf_get_ns_current_pid_tgid_proto = {
		.func = bpf_get_ns_current_pid_tgid,
		.gpl_only = false,
		.ret_type = RET_INTEGER,
		.arg1_type = ARG_ANYTHING,
		.arg2_type = ARG_ANYTHING,
		.arg3_type = ARG_PTR_TO_UNINIT_MEM,
		.arg4_type = ARG_CONST_SIZE,
		};

+2 −0

Original line number	Diff line number	Diff line
		@@ -843,6 +843,8 @@ tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
		return &bpf_send_signal_thread_proto;
		case BPF_FUNC_perf_event_read_value:
		return &bpf_perf_event_read_value_proto;
		case BPF_FUNC_get_ns_current_pid_tgid:
		return &bpf_get_ns_current_pid_tgid_proto;
		default:
		return NULL;
		}