On 9/12/22 11:11 AM, Dave Marchevsky wrote:
After the previous patch, which added PTR_TO_MEM types to
map_key_value_types, the only difference between map_key_value_types and
mem_types sets is PTR_TO_BUF, which is in the latter set but not the
former.
Add a selftest with PTR_TO_BUF as the map key/value?
Helpers which expect ARG_PTR_TO_MAP_KEY or ARG_PTR_TO_MAP_VALUE
already effectively expect a valid blob of arbitrary memory that isn't
necessarily explicitly associated with a map. When validating a
PTR_TO_MAP_{KEY,VALUE} arg, the verifier expects meta->map_ptr to have
already been set, either by an earlier ARG_CONST_MAP_PTR arg, or custom
logic like that in process_timer_func or process_kptr_func.
So let's get rid of map_key_value_types and just use mem_types for those
args.
This has the effect of adding PTR_TO_BUF to the set of compatible types
for ARG_PTR_TO_MAP_KEY and ARG_PTR_TO_MAP_VALUE.
Signed-off-by: Dave Marchevsky <davemarchevsky@xxxxxx>
---
kernel/bpf/verifier.c | 16 ++--------------
1 file changed, 2 insertions(+), 14 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index d093618aed99..ae2259d782bb 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5619,18 +5619,6 @@ struct bpf_reg_types {
u32 *btf_id;
};
-static const struct bpf_reg_types map_key_value_types = {
- .types = {
- PTR_TO_STACK,
- PTR_TO_PACKET,
- PTR_TO_PACKET_META,
- PTR_TO_MAP_KEY,
- PTR_TO_MAP_VALUE,
- PTR_TO_MEM,
- PTR_TO_MEM | MEM_ALLOC,
- },
-};
-
static const struct bpf_reg_types sock_types = {
.types = {
PTR_TO_SOCK_COMMON,
@@ -5691,8 +5679,8 @@ static const struct bpf_reg_types timer_types = { .types = { PTR_TO_MAP_VALUE }
static const struct bpf_reg_types kptr_types = { .types = { PTR_TO_MAP_VALUE } };
static const struct bpf_reg_types *compatible_reg_types[__BPF_ARG_TYPE_MAX] = {
- [ARG_PTR_TO_MAP_KEY] = &map_key_value_types,
- [ARG_PTR_TO_MAP_VALUE] = &map_key_value_types,
+ [ARG_PTR_TO_MAP_KEY] = &mem_types,
+ [ARG_PTR_TO_MAP_VALUE] = &mem_types,
[ARG_CONST_SIZE] = &scalar_types,
[ARG_CONST_SIZE_OR_ZERO] = &scalar_types,
[ARG_CONST_ALLOC_SIZE_OR_ZERO] = &scalar_types,
