It is to unify map flags checking for lookup_elem, update_elem, lookup_batch and update_batch APIs.
Therefore, it will be convenient to check BPF_F_CPU and BPF_F_ALL_CPUS flags in it for these APIs in next patch.
Acked-by: Andrii Nakryiko andrii@kernel.org Signed-off-by: Leon Hwang leon.hwang@linux.dev --- include/linux/bpf.h | 11 +++++++++++ kernel/bpf/syscall.c | 34 +++++++++++----------------------- 2 files changed, 22 insertions(+), 23 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index a9b788c7b4aa..6498be4c44f8 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -3829,4 +3829,15 @@ bpf_prog_update_insn_ptrs(struct bpf_prog *prog, u32 *offsets, void *image) } #endif
+static inline int bpf_map_check_op_flags(struct bpf_map *map, u64 flags, u64 allowed_flags) +{ + if (flags & ~allowed_flags) + return -EINVAL; + + if ((flags & BPF_F_LOCK) && !btf_record_has_field(map->record, BPF_SPIN_LOCK)) + return -EINVAL; + + return 0; +} + #endif /* _LINUX_BPF_H */ diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 792623a7c90b..cef8963d69f9 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1725,9 +1725,6 @@ static int map_lookup_elem(union bpf_attr *attr) if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) return -EINVAL;
- if (attr->flags & ~BPF_F_LOCK) - return -EINVAL; - CLASS(fd, f)(attr->map_fd); map = __bpf_map_get(f); if (IS_ERR(map)) @@ -1735,9 +1732,9 @@ static int map_lookup_elem(union bpf_attr *attr) if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) return -EPERM;
- if ((attr->flags & BPF_F_LOCK) && - !btf_record_has_field(map->record, BPF_SPIN_LOCK)) - return -EINVAL; + err = bpf_map_check_op_flags(map, attr->flags, BPF_F_LOCK); + if (err) + return err;
key = __bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) @@ -1800,11 +1797,9 @@ static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) goto err_put; }
- if ((attr->flags & BPF_F_LOCK) && - !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { - err = -EINVAL; + err = bpf_map_check_op_flags(map, attr->flags, ~0); + if (err) goto err_put; - }
key = ___bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) { @@ -2008,13 +2003,9 @@ int generic_map_update_batch(struct bpf_map *map, struct file *map_file, void *key, *value; int err = 0;
- if (attr->batch.elem_flags & ~BPF_F_LOCK) - return -EINVAL; - - if ((attr->batch.elem_flags & BPF_F_LOCK) && - !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { - return -EINVAL; - } + err = bpf_map_check_op_flags(map, attr->batch.elem_flags, BPF_F_LOCK); + if (err) + return err;
value_size = bpf_map_value_size(map);
@@ -2071,12 +2062,9 @@ int generic_map_lookup_batch(struct bpf_map *map, u32 value_size, cp, max_count; int err;
- if (attr->batch.elem_flags & ~BPF_F_LOCK) - return -EINVAL; - - if ((attr->batch.elem_flags & BPF_F_LOCK) && - !btf_record_has_field(map->record, BPF_SPIN_LOCK)) - return -EINVAL; + err = bpf_map_check_op_flags(map, attr->batch.elem_flags, BPF_F_LOCK); + if (err) + return err;
value_size = bpf_map_value_size(map);