On 8/3/23 12:36, Michal Privoznik wrote:
> If one of previous commits taught us something, it's that:
> sizeof(variable) and sizeof(type) are not the same. Especially
> because for live enough code the type might change (e.g. as we
> use autoptr more). And since we don't get any warnings when an
> incorrect length is passed to memset() it is easy to mess up. But
> with sizeof(variable) instead, it's not as easy. Therefore,
> switch to using memset(variable, 0, sizeof(*variable)), or its
> alternatives, depending on level of pointers.
>
> Signed-off-by: Michal Privoznik <mprivozn@xxxxxxxxxx>
Reviewed-by: Claudio Fontana <cfontana@xxxxxxx>
> ---
> src/qemu/qemu_monitor_json.c | 4 ++--
> src/qemu/qemu_process.c | 2 +-
> src/remote/remote_driver.c | 2 +-
> src/storage/storage_driver.c | 2 +-
> src/test/test_driver.c | 4 ++--
> 5 files changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
> index 70536028ab..34c4b543e8 100644
> --- a/src/qemu/qemu_monitor_json.c
> +++ b/src/qemu/qemu_monitor_json.c
> @@ -7112,7 +7112,7 @@ qemuMonitorJSONSetIOThread(qemuMonitor *mon,
>
> #define VIR_IOTHREAD_SET_PROP_UL(propName, propVal) \
> if (iothreadInfo->set_##propVal) { \
> - memset(&prop, 0, sizeof(qemuMonitorJSONObjectProperty)); \
> + memset(&prop, 0, sizeof(prop)); \
> prop.type = QEMU_MONITOR_OBJECT_PROPERTY_ULONG; \
> prop.val.ul = iothreadInfo->propVal; \
> if (qemuMonitorJSONSetObjectProperty(mon, path, propName, &prop) < 0) \
> @@ -7145,7 +7145,7 @@ qemuMonitorJSONSetIOThread(qemuMonitor *mon,
>
> #define VIR_IOTHREAD_SET_PROP_INT(propName, propVal) \
> if (iothreadInfo->set_##propVal) { \
> - memset(&prop, 0, sizeof(qemuMonitorJSONObjectProperty)); \
> + memset(&prop, 0, sizeof(prop)); \
> prop.type = QEMU_MONITOR_OBJECT_PROPERTY_INT; \
> prop.val.iv = iothreadInfo->propVal; \
> if (qemuMonitorJSONSetObjectProperty(mon, path, propName, &prop) < 0) \
> diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
> index 572b842349..0644f80161 100644
> --- a/src/qemu/qemu_process.c
> +++ b/src/qemu/qemu_process.c
> @@ -5068,7 +5068,7 @@ qemuProcessGraphicsSetupListen(virQEMUDriver *driver,
> * *_auto_unix_socket set we should use unix socket as
> * default instead of tcp listen. */
> if (useSocket) {
> - memset(glisten, 0, sizeof(virDomainGraphicsListenDef));
> + memset(glisten, 0, sizeof(*glisten));
> glisten->socket = g_strdup_printf("%s/%s.sock", priv->libDir,
> type);
> glisten->fromConfig = true;
> diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c
> index 8e78af0ea0..faad7292ed 100644
> --- a/src/remote/remote_driver.c
> +++ b/src/remote/remote_driver.c
> @@ -2138,7 +2138,7 @@ remoteDomainGetVcpus(virDomainPtr domain,
> goto cleanup;
> }
>
> - memset(info, 0, sizeof(virVcpuInfo) * maxinfo);
> + memset(info, 0, sizeof(*info) * maxinfo);
> memset(cpumaps, 0, maxinfo * maplen);
>
> for (i = 0; i < ret.info.info_len; ++i) {
> diff --git a/src/storage/storage_driver.c b/src/storage/storage_driver.c
> index c19abdd2f3..5a9dcbd193 100644
> --- a/src/storage/storage_driver.c
> +++ b/src/storage/storage_driver.c
> @@ -1279,7 +1279,7 @@ storagePoolGetInfo(virStoragePoolPtr pool,
> if (virStorageBackendForType(def->type) == NULL)
> goto cleanup;
>
> - memset(info, 0, sizeof(virStoragePoolInfo));
> + memset(info, 0, sizeof(*info));
> if (virStoragePoolObjIsActive(obj))
> info->state = VIR_STORAGE_POOL_RUNNING;
> else
> diff --git a/src/test/test_driver.c b/src/test/test_driver.c
> index 3767908d9d..4b8e02c684 100644
> --- a/src/test/test_driver.c
> +++ b/src/test/test_driver.c
> @@ -4826,7 +4826,7 @@ static int testDomainGetDiskErrors(virDomainPtr dom,
>
> if (errors) {
> /* sanitize input */
> - memset(errors, 0, sizeof(virDomainDiskError) * nerrors);
> + memset(errors, 0, sizeof(*errors) * nerrors);
>
> for (i = 0; i < nerrors; i++) {
> errors[i].disk = g_strdup(vm->def->disks[i]->dst);
> @@ -6878,7 +6878,7 @@ testStoragePoolGetInfo(virStoragePoolPtr pool,
> return -1;
> def = virStoragePoolObjGetDef(obj);
>
> - memset(info, 0, sizeof(virStoragePoolInfo));
> + memset(info, 0, sizeof(*info));
> if (virStoragePoolObjIsActive(obj))
> info->state = VIR_STORAGE_POOL_RUNNING;
> else
