On 8/12/24 10:36, Alexei Starovoitov wrote:
On Mon, Aug 12, 2024 at 10:24 AM Kui-Feng Lee <sinquersw@xxxxxxxxx> wrote:
+static int bpf_map_update_value(struct bpf_map *map, struct file *map_file,
+ void *key, void *value, __u64 flags)
+{
+ int err;
+
+ if (flags & BPF_FROM_USER) {
there shouldn't be a need for this extra flag.
map->record has the info whether uptr is present or not.
The BPF_FROM_USER flag is used to support updating map values from BPF
programs as well. Although BPF programs can udpate map values, I
don't want the values of uptrs to be changed by the BPF programs.
Should we just forbid the BPF programs to udpate the map values having
uptrs in them?
hmm. map_update_elem() is disallowed from bpf prog.
case BPF_MAP_TYPE_TASK_STORAGE:
if (func_id != BPF_FUNC_task_storage_get &&
func_id != BPF_FUNC_task_storage_delete &&
func_id != BPF_FUNC_kptr_xchg)
goto error;
Thank you for the information!
