23.12.2019 12:06, Eiichi Tsukata wrote:
> bdrv_open_driver() allocates bs->opaque according to drv->instance_size.
> There is no need to allocate it and overwrite opaque in
> bdrv_backup_top_append().
>
> Reproducer:
>
> $ QTEST_QEMU_BINARY=./x86_64-softmmu/qemu-system-x86_64 valgrind -q
> --leak-check=full tests/test-replication -p /replication/secondary/start
> ==29792== 24 bytes in 1 blocks are definitely lost in loss record 52 of 226
> ==29792== at 0x483AB1A: calloc (vg_replace_malloc.c:762)
> ==29792== by 0x4B07CE0: g_malloc0 (in
> /usr/lib64/libglib-2.0.so.0.6000.7)
> ==29792== by 0x12BAB9: bdrv_open_driver (block.c:1289)
> ==29792== by 0x12BEA9: bdrv_new_open_driver (block.c:1359)
> ==29792== by 0x1D15CB: bdrv_backup_top_append (backup-top.c:190)
> ==29792== by 0x1CC11A: backup_job_create (backup.c:439)
> ==29792== by 0x1CD542: replication_start (replication.c:544)
> ==29792== by 0x1401B9: replication_start_all (replication.c:52)
> ==29792== by 0x128B50: test_secondary_start (test-replication.c:427)
> ...
>
> Fixes: 7df7868b9640 ("block: introduce backup-top filter driver")
> Signed-off-by: Eiichi Tsukata <de...@etsukata.com>
> ---
> block/backup-top.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/block/backup-top.c b/block/backup-top.c
> index 7cdb1f8eba..617217374d 100644
> --- a/block/backup-top.c
> +++ b/block/backup-top.c
> @@ -196,7 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState
> *source,
> }
>
> top->total_sectors = source->total_sectors;
> - top->opaque = state = g_new0(BDRVBackupTopState, 1);
> + state = top->opaque;
>
> bdrv_ref(target);
> state->target = bdrv_attach_child(top, target, "target", &child_file,
> errp);
>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Hmm, it was not my idea, I just copied it from mirror.. And there should be the
same leak. and
may be in other places:
# git grep 'opaque =.*g_new'
block/backup-top.c: top->opaque = state = g_new0(BDRVBackupTopState, 1);
block/file-posix.c: state->opaque = g_new0(BDRVRawReopenState, 1);
block/gluster.c: state->opaque = g_new0(BDRVGlusterReopenState, 1);
block/iscsi.c: bs->opaque = g_new0(struct IscsiLun, 1);
block/mirror.c: bs_opaque = g_new0(MirrorBDSOpaque, 1);
block/raw-format.c: reopen_state->opaque = g_new0(BDRVRawState, 1);
block/sheepdog.c: re_s = state->opaque = g_new0(BDRVSheepdogReopenState, 1);
--
Best regards,
Vladimir
