On Fri, Oct 6, 2023 at 10:41 PM Matheus Tavares Bernardino <
quic_mathb...@quicinc.com> wrote:
> When the given uuid is already present in the hash table,
> virtio_add_resource() does not add the passed VirtioSharedObject. In
> this case, free it in the callers to avoid leaking memory. This fixed
> the following `make check` error, when built with --enable-sanitizers:
>
> 4/166 qemu:unit / test-virtio-dmabuf ERROR 1.51s exit status 1
>
> ==7716==ERROR: LeakSanitizer: detected memory leaks
> Direct leak of 320 byte(s) in 20 object(s) allocated from:
> #0 0x7f6fc16e3808 in __interceptor_malloc
> ../../../../src/libsanitizer/asan/asan_malloc_linux.cc:144
> #1 0x7f6fc1503e98 in g_malloc
> (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x57e98)
> #2 0x564d63cafb6b in test_add_invalid_resource
> ../tests/unit/test-virtio-dmabuf.c:100
> #3 0x7f6fc152659d (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x7a59d)
> SUMMARY: AddressSanitizer: 320 byte(s) leaked in 20 allocation(s).
>
> The changes at virtio_add_resource() itself are not strictly necessary
> for the memleak fix, but they make it more obvious that, on an error
> return, the passed object is not added to the hash.
>
> Signed-off-by: Matheus Tavares Bernardino
> ---
> hw/display/virtio-dmabuf.c | 12 ++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/hw/display/virtio-dmabuf.c b/hw/display/virtio-dmabuf.c
> index 4a8e430f3d..3dba4577ca 100644
> --- a/hw/display/virtio-dmabuf.c
> +++ b/hw/display/virtio-dmabuf.c
> @@ -29,7 +29,7 @@ static int uuid_equal_func(const void *lhv, const void
> *rhv)
>
> static bool virtio_add_resource(QemuUUID *uuid, VirtioSharedObject *value)
> {
> -bool result = false;
> +bool result = true;
>
> g_mutex_lock();
> if (resource_uuids == NULL) {
> @@ -39,7 +39,9 @@ static bool virtio_add_resource(QemuUUID *uuid,
> VirtioSharedObject *value)
> g_free);
> }
> if (g_hash_table_lookup(resource_uuids, uuid) == NULL) {
> -result = g_hash_table_insert(resource_uuids, uuid, value);
> +g_hash_table_insert(resource_uuids, uuid, value);
> +} else {
> +result = false;
> }
> g_mutex_unlock();
>
> @@ -57,6 +59,9 @@ bool virtio_add_dmabuf(QemuUUID *uuid, int udmabuf_fd)
> vso->type = TYPE_DMABUF;
> vso->value = GINT_TO_POINTER(udmabuf_fd);
> result = virtio_add_resource(uuid, vso);
> +if (!result) {
> +g_free(vso);
> +}
>
> return result;
> }
> @@ -72,6 +77,9 @@ bool virtio_add_vhost_device(QemuUUID *uuid, struct
> vhost_dev *dev)
> vso->type = TYPE_VHOST_DEV;
> vso->value = dev;
> result = virtio_add_resource(uuid, vso);
> +if (!result) {
> +g_free(vso);
> +}
>
> return result;
> }
> --
> 2.37.2
>
>
Thanks!
Reviewed-by: Albert Esteve
