hw/arm/boot: Correctly free the MemoryDeviceInfoList

When running the bios-tables-test under ASAN we see leaks like this:

Direct leak of 16 byte(s) in 1 object(s) allocated from:
    #0 0x5bc58579b00d in calloc (/mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/qemu-system-aarch64+0x250400d) (BuildId: 2e27b63dc9ac45f522ced40a17c2a60cc32f1d38)
    #1 0x7b4ad90337b1 in g_malloc0 (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x637b1) (BuildId: 1eb6131419edb83b2178b682829a6913cf682d75)
    #2 0x5bc5861826db in qmp_memory_device_list /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/../../hw/mem/memory-device.c:307:34
    #3 0x5bc587a9edb6 in arm_load_dtb /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/../../hw/arm/boot.c:656:15

Indirect leak of 28 byte(s) in 2 object(s) allocated from:
    #0 0x5bc58579ae23 in malloc (/mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/qemu-system-aarch64+0x2503e23) (BuildId: 2e27b63dc9ac45f522ced40a17c2a60cc32f1d38)
    #1 0x7b4ad6c8f947 in __vasprintf_internal libio/vasprintf.c:116:16
    #2 0x7b4ad9080a52 in g_vasprintf (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0xb0a52) (BuildId: 1eb6131419edb83b2178b682829a6913cf682d75)
    #3 0x7b4ad90515e4 in g_strdup_vprintf (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x815e4) (BuildId: 1eb6131419edb83b2178b682829a6913cf682d75)
    #4 0x7b4ad9051940 in g_strdup_printf (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x81940) (BuildId: 1eb6131419edb83b2178b682829a6913cf682d75)
    #5 0x5bc5885eb739 in object_get_canonical_path /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/../../qom/object.c:2123:19
    qemu#6 0x5bc58618dca8 in pc_dimm_md_fill_device_info /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/../../hw/mem/pc-dimm.c:268:18
    qemu#7 0x5bc586182792 in qmp_memory_device_list /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-asan/../../hw/mem/memory-device.c:310:9

This happens because we declared the MemoryDeviceInfoList *md_list
with g_autofree, which will free the direct memory with g_free() but
doesn't free all the other data structures referenced by it.  Instead
what we want is to declare the pointer with g_autoptr(), which will
automatically call the qapi_free_MemoryDeviceInfoList() cleanup
function when the variable goes out of scope.

Fixes: 36bc78a ("hw/arm: add static NVDIMMs in device tree")
Signed-off-by: Peter Maydell <[email protected]>
Reviewed-by: Manos Pitsidianakis <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Message-ID: <[email protected]>
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>

Author: pm215

hw/arm/boot.c

@@ -549,7 +549,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
     unsigned int i;
     hwaddr mem_base, mem_len;
     char **node_path;
-    g_autofree MemoryDeviceInfoList *md_list = NULL;
+    g_autoptr(MemoryDeviceInfoList) md_list = NULL;
     Error *err = NULL;
 
     if (binfo->dtb_filename) {