ucode-mod-bpf: fix unaligned access in integer iterator

The iterator key buffer is a flexible array member placed directly
after a bool, leaving it without natural alignment for the u32/u64
loads in next_int. Copy the key via memcpy instead of dereferencing
a misaligned pointer, which traps on strict-alignment targets.

Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/package/utils/ucode-mod-bpf/src/bpf.c b/package/utils/ucode-mod-bpf/src/bpf.c
index 1758510a54e82551b13ebe8d2b315c8954ce8a52..eb7d5a03ac3515f773ba97ef0ad893179ada1b17 100644 (file)
--- a/package/utils/ucode-mod-bpf/src/bpf.c
+++ b/package/utils/ucode-mod-bpf/src/bpf.c
@@ -544,12 +544,16 @@ uc_bpf_map_iter_next_int(uc_vm_t *vm, size_t nargs)
        if (!iter->has_next)
                return NULL;
 
-       if (iter->key_size == 4)
-               intval = *(uint32_t *)iter->key;
-       else if (iter->key_size == 8)
-               intval = *(uint64_t *)iter->key;
-       else
+       if (iter->key_size == 4) {
+               uint32_t val32;
+
+               memcpy(&val32, iter->key, sizeof(val32));
+               intval = val32;
+       } else if (iter->key_size == 8) {
+               memcpy(&intval, iter->key, sizeof(intval));
+       } else {
                return NULL;
+       }
 
        rv = ucv_int64_new(intval);
        iter->has_next = !bpf_map_get_next_key(iter->fd, &iter->key, &iter->key);