diff options
Diffstat (limited to 'kernel/bpf/syscall.c')
-rw-r--r-- | kernel/bpf/syscall.c | 245 |
1 files changed, 226 insertions, 19 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index bfcde949c7f8..388d4feda348 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -18,7 +18,9 @@ #include <linux/vmalloc.h> #include <linux/mmzone.h> #include <linux/anon_inodes.h> +#include <linux/fdtable.h> #include <linux/file.h> +#include <linux/fs.h> #include <linux/license.h> #include <linux/filter.h> #include <linux/version.h> @@ -65,9 +67,9 @@ static const struct bpf_map_ops * const bpf_map_types[] = { * copy_from_user() call. However, this is not a concern since this function is * meant to be a future-proofing of bits. */ -static int check_uarg_tail_zero(void __user *uaddr, - size_t expected_size, - size_t actual_size) +int bpf_check_uarg_tail_zero(void __user *uaddr, + size_t expected_size, + size_t actual_size) { unsigned char __user *addr; unsigned char __user *end; @@ -422,7 +424,7 @@ static int bpf_obj_name_cpy(char *dst, const char *src) return 0; } -#define BPF_MAP_CREATE_LAST_FIELD btf_value_id +#define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id /* called via syscall */ static int map_create(union bpf_attr *attr) { @@ -457,10 +459,10 @@ static int map_create(union bpf_attr *attr) atomic_set(&map->usercnt, 1); if (bpf_map_support_seq_show(map) && - (attr->btf_key_id || attr->btf_value_id)) { + (attr->btf_key_type_id || attr->btf_value_type_id)) { struct btf *btf; - if (!attr->btf_key_id || !attr->btf_value_id) { + if (!attr->btf_key_type_id || !attr->btf_value_type_id) { err = -EINVAL; goto free_map_nouncharge; } @@ -471,16 +473,16 @@ static int map_create(union bpf_attr *attr) goto free_map_nouncharge; } - err = map->ops->map_check_btf(map, btf, attr->btf_key_id, - attr->btf_value_id); + err = map->ops->map_check_btf(map, btf, attr->btf_key_type_id, + attr->btf_value_type_id); if (err) { btf_put(btf); goto free_map_nouncharge; } map->btf = btf; - map->btf_key_id = attr->btf_key_id; - map->btf_value_id = attr->btf_value_id; + map->btf_key_type_id = attr->btf_key_type_id; + map->btf_value_type_id = attr->btf_value_type_id; } err = security_bpf_map_alloc(map); @@ -1899,7 +1901,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, u32 ulen; int err; - err = check_uarg_tail_zero(uinfo, sizeof(info), info_len); + err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); if (err) return err; info_len = min_t(u32, sizeof(info), info_len); @@ -1933,6 +1935,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, if (!capable(CAP_SYS_ADMIN)) { info.jited_prog_len = 0; info.xlated_prog_len = 0; + info.nr_jited_ksyms = 0; goto done; } @@ -1969,18 +1972,93 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, * for offload. */ ulen = info.jited_prog_len; - info.jited_prog_len = prog->jited_len; + if (prog->aux->func_cnt) { + u32 i; + + info.jited_prog_len = 0; + for (i = 0; i < prog->aux->func_cnt; i++) + info.jited_prog_len += prog->aux->func[i]->jited_len; + } else { + info.jited_prog_len = prog->jited_len; + } + if (info.jited_prog_len && ulen) { if (bpf_dump_raw_ok()) { uinsns = u64_to_user_ptr(info.jited_prog_insns); ulen = min_t(u32, info.jited_prog_len, ulen); - if (copy_to_user(uinsns, prog->bpf_func, ulen)) - return -EFAULT; + + /* for multi-function programs, copy the JITed + * instructions for all the functions + */ + if (prog->aux->func_cnt) { + u32 len, free, i; + u8 *img; + + free = ulen; + for (i = 0; i < prog->aux->func_cnt; i++) { + len = prog->aux->func[i]->jited_len; + len = min_t(u32, len, free); + img = (u8 *) prog->aux->func[i]->bpf_func; + if (copy_to_user(uinsns, img, len)) + return -EFAULT; + uinsns += len; + free -= len; + if (!free) + break; + } + } else { + if (copy_to_user(uinsns, prog->bpf_func, ulen)) + return -EFAULT; + } } else { info.jited_prog_insns = 0; } } + ulen = info.nr_jited_ksyms; + info.nr_jited_ksyms = prog->aux->func_cnt; + if (info.nr_jited_ksyms && ulen) { + if (bpf_dump_raw_ok()) { + u64 __user *user_ksyms; + ulong ksym_addr; + u32 i; + + /* copy the address of the kernel symbol + * corresponding to each function + */ + ulen = min_t(u32, info.nr_jited_ksyms, ulen); + user_ksyms = u64_to_user_ptr(info.jited_ksyms); + for (i = 0; i < ulen; i++) { + ksym_addr = (ulong) prog->aux->func[i]->bpf_func; + ksym_addr &= PAGE_MASK; + if (put_user((u64) ksym_addr, &user_ksyms[i])) + return -EFAULT; + } + } else { + info.jited_ksyms = 0; + } + } + + ulen = info.nr_jited_func_lens; + info.nr_jited_func_lens = prog->aux->func_cnt; + if (info.nr_jited_func_lens && ulen) { + if (bpf_dump_raw_ok()) { + u32 __user *user_lens; + u32 func_len, i; + + /* copy the JITed image lengths for each function */ + ulen = min_t(u32, info.nr_jited_func_lens, ulen); + user_lens = u64_to_user_ptr(info.jited_func_lens); + for (i = 0; i < ulen; i++) { + func_len = prog->aux->func[i]->jited_len; + if (put_user(func_len, &user_lens[i])) + return -EFAULT; + } + } else { + info.jited_func_lens = 0; + } + } + done: if (copy_to_user(uinfo, &info, info_len) || put_user(info_len, &uattr->info.info_len)) @@ -1998,7 +2076,7 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map, u32 info_len = attr->info.info_len; int err; - err = check_uarg_tail_zero(uinfo, sizeof(info), info_len); + err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len); if (err) return err; info_len = min_t(u32, sizeof(info), info_len); @@ -2013,8 +2091,8 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map, if (map->btf) { info.btf_id = btf_id(map->btf); - info.btf_key_id = map->btf_key_id; - info.btf_value_id = map->btf_value_id; + info.btf_key_type_id = map->btf_key_type_id; + info.btf_value_type_id = map->btf_value_type_id; } if (bpf_map_is_dev_bound(map)) { @@ -2038,7 +2116,7 @@ static int bpf_btf_get_info_by_fd(struct btf *btf, u32 info_len = attr->info.info_len; int err; - err = check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); + err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len); if (err) return err; @@ -2102,6 +2180,132 @@ static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) return btf_get_fd_by_id(attr->btf_id); } +static int bpf_task_fd_query_copy(const union bpf_attr *attr, + union bpf_attr __user *uattr, + u32 prog_id, u32 fd_type, + const char *buf, u64 probe_offset, + u64 probe_addr) +{ + char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); + u32 len = buf ? strlen(buf) : 0, input_len; + int err = 0; + + if (put_user(len, &uattr->task_fd_query.buf_len)) + return -EFAULT; + input_len = attr->task_fd_query.buf_len; + if (input_len && ubuf) { + if (!len) { + /* nothing to copy, just make ubuf NULL terminated */ + char zero = '\0'; + + if (put_user(zero, ubuf)) + return -EFAULT; + } else if (input_len >= len + 1) { + /* ubuf can hold the string with NULL terminator */ + if (copy_to_user(ubuf, buf, len + 1)) + return -EFAULT; + } else { + /* ubuf cannot hold the string with NULL terminator, + * do a partial copy with NULL terminator. + */ + char zero = '\0'; + + err = -ENOSPC; + if (copy_to_user(ubuf, buf, input_len - 1)) + return -EFAULT; + if (put_user(zero, ubuf + input_len - 1)) + return -EFAULT; + } + } + + if (put_user(prog_id, &uattr->task_fd_query.prog_id) || + put_user(fd_type, &uattr->task_fd_query.fd_type) || + put_user(probe_offset, &uattr->task_fd_query.probe_offset) || + put_user(probe_addr, &uattr->task_fd_query.probe_addr)) + return -EFAULT; + + return err; +} + +#define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr + +static int bpf_task_fd_query(const union bpf_attr *attr, + union bpf_attr __user *uattr) +{ + pid_t pid = attr->task_fd_query.pid; + u32 fd = attr->task_fd_query.fd; + const struct perf_event *event; + struct files_struct *files; + struct task_struct *task; + struct file *file; + int err; + + if (CHECK_ATTR(BPF_TASK_FD_QUERY)) + return -EINVAL; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (attr->task_fd_query.flags != 0) + return -EINVAL; + + task = get_pid_task(find_vpid(pid), PIDTYPE_PID); + if (!task) + return -ENOENT; + + files = get_files_struct(task); + put_task_struct(task); + if (!files) + return -ENOENT; + + err = 0; + spin_lock(&files->file_lock); + file = fcheck_files(files, fd); + if (!file) + err = -EBADF; + else + get_file(file); + spin_unlock(&files->file_lock); + put_files_struct(files); + + if (err) + goto out; + + if (file->f_op == &bpf_raw_tp_fops) { + struct bpf_raw_tracepoint *raw_tp = file->private_data; + struct bpf_raw_event_map *btp = raw_tp->btp; + + err = bpf_task_fd_query_copy(attr, uattr, + raw_tp->prog->aux->id, + BPF_FD_TYPE_RAW_TRACEPOINT, + btp->tp->name, 0, 0); + goto put_file; + } + + event = perf_get_event(file); + if (!IS_ERR(event)) { + u64 probe_offset, probe_addr; + u32 prog_id, fd_type; + const char *buf; + + err = bpf_get_perf_event_info(event, &prog_id, &fd_type, + &buf, &probe_offset, + &probe_addr); + if (!err) + err = bpf_task_fd_query_copy(attr, uattr, prog_id, + fd_type, buf, + probe_offset, + probe_addr); + goto put_file; + } + + err = -ENOTSUPP; +put_file: + fput(file); +out: + return err; +} + SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) { union bpf_attr attr = {}; @@ -2110,7 +2314,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) return -EPERM; - err = check_uarg_tail_zero(uattr, sizeof(attr), size); + err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); if (err) return err; size = min_t(u32, size, sizeof(attr)); @@ -2188,6 +2392,9 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz case BPF_BTF_GET_FD_BY_ID: err = bpf_btf_get_fd_by_id(&attr); break; + case BPF_TASK_FD_QUERY: + err = bpf_task_fd_query(&attr, uattr); + break; default: err = -EINVAL; break; |