diff options
| -rw-r--r-- | include/linux/bpf.h | 1 | ||||
| -rw-r--r-- | include/uapi/linux/bpf.h | 20 | ||||
| -rw-r--r-- | kernel/bpf/core.c | 1 | ||||
| -rw-r--r-- | kernel/bpf/helpers.c | 45 | ||||
| -rw-r--r-- | kernel/trace/bpf_trace.c | 2 | ||||
| -rwxr-xr-x | scripts/bpf_helpers_doc.py | 1 | ||||
| -rw-r--r-- | tools/include/uapi/linux/bpf.h | 20 |
7 files changed, 88 insertions, 2 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 4fd91b7c95ea..4ec835334a1f 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -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); diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 40b2d9476268..15b239da775b 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -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__ */ diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 973a20d49749..0f9ca46e1978 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -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) { diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index d8b7b110a1c5..01878db15eaf 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -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, +}; diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 6a490d8ce9de..b5071c7e93ca 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -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; } diff --git a/scripts/bpf_helpers_doc.py b/scripts/bpf_helpers_doc.py index cebed6fb5bbb..c1e2b5410faa 100755 --- a/scripts/bpf_helpers_doc.py +++ b/scripts/bpf_helpers_doc.py @@ -435,6 +435,7 @@ class PrinterHelpers(Printer): 'struct bpf_fib_lookup', 'struct bpf_perf_event_data', 'struct bpf_perf_event_value', + 'struct bpf_pidns_info', 'struct bpf_sock', 'struct bpf_sock_addr', 'struct bpf_sock_ops', diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 40b2d9476268..15b239da775b 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -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__ */ |