As [lru_,]percpu_hash maps support BPF_KPTR_{REF,PERCPU}, missing calls to 'bpf_obj_free_fields()' in 'pcpu_copy_value()' could cause the memory referenced by BPF_KPTR_{REF,PERCPU} fields to be held until the map gets freed. Fix this by calling 'bpf_obj_free_fields()' after 'copy_map_value[,_long]()' in 'pcpu_copy_value()'. Fixes: 65334e64a493 ("bpf: Support kptrs in percpu hashmap and percpu LRU hashmap") Signed-off-by: Leon Hwang --- kernel/bpf/hashtab.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index c2fcd0cd51e51..26308adc9ccb3 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -950,12 +950,14 @@ static void pcpu_copy_value(struct bpf_htab *htab, void __percpu *pptr, if (!onallcpus) { /* copy true value_size bytes */ copy_map_value(&htab->map, this_cpu_ptr(pptr), value); + bpf_obj_free_fields(htab->map.record, this_cpu_ptr(pptr)); } else { u32 size = round_up(htab->map.value_size, 8); int off = 0, cpu; for_each_possible_cpu(cpu) { copy_map_value_long(&htab->map, per_cpu_ptr(pptr, cpu), value + off); + bpf_obj_free_fields(htab->map.record, per_cpu_ptr(pptr, cpu)); off += size; } } -- 2.51.0