Re: [PATCH 1/2] migration/multifd: fix memleaks in multifd_new_send_channel_async

[Juan Quintela <quintela@redhat.com>]

Pan Nengyuan <pannengyuan@huawei.com> wrote:
> When error happen in multifd_new_send_channel_async, 'sioc' will not be used
> to create the multifd_send_thread. Let's free it to avoid a memleak. And also
> do error_free after migrate_set_error() to avoid another leak in the same place.
>
> The leak stack:
> Direct leak of 2880 byte(s) in 8 object(s) allocated from:
>     #0 0x7f20b5118ae8 in __interceptor_malloc (/lib64/libasan.so.5+0xefae8)
>     #1 0x7f20b44df1d5 in g_malloc (/lib64/libglib-2.0.so.0+0x531d5)
>     #2 0x564133bce18b in object_new_with_type /mnt/sdb/backup/qemu/qom/object.c:683
>     #3 0x564133eea950 in qio_channel_socket_new /mnt/sdb/backup/qemu/io/channel-socket.c:56
>     #4 0x5641339cfe4f in socket_send_channel_create /mnt/sdb/backup/qemu/migration/socket.c:37
>     #5 0x564133a10328 in multifd_save_setup /mnt/sdb/backup/qemu/migration/multifd.c:772
>     #6 0x5641339cebed in migrate_fd_connect /mnt/sdb/backup/qemu/migration/migration.c:3530
>     #7 0x5641339d15e4 in migration_channel_connect /mnt/sdb/backup/qemu/migration/channel.c:92
>     #8 0x5641339cf5b7 in socket_outgoing_migration /mnt/sdb/backup/qemu/migration/socket.c:108
>
> Direct leak of 384 byte(s) in 8 object(s) allocated from:
>     #0 0x7f20b5118cf0 in calloc (/lib64/libasan.so.5+0xefcf0)
>     #1 0x7f20b44df22d in g_malloc0 (/lib64/libglib-2.0.so.0+0x5322d)
>     #2 0x56413406fc17 in error_setv /mnt/sdb/backup/qemu/util/error.c:61
>     #3 0x564134070464 in error_setg_errno_internal /mnt/sdb/backup/qemu/util/error.c:109
>     #4 0x5641340851be in inet_connect_addr /mnt/sdb/backup/qemu/util/qemu-sockets.c:379
>     #5 0x5641340851be in inet_connect_saddr /mnt/sdb/backup/qemu/util/qemu-sockets.c:458
>     #6 0x5641340870ab in socket_connect /mnt/sdb/backup/qemu/util/qemu-sockets.c:1105
>     #7 0x564133eeaabf in qio_channel_socket_connect_sync /mnt/sdb/backup/qemu/io/channel-socket.c:145
>     #8 0x564133eeabf5 in qio_channel_socket_connect_worker /mnt/sdb/backup/qemu/io/channel-socket.c:168
>
> Indirect leak of 360 byte(s) in 8 object(s) allocated from:
>     #0 0x7f20b5118ae8 in __interceptor_malloc (/lib64/libasan.so.5+0xefae8)
>     #1 0x7f20af901817 in __GI___vasprintf_chk (/lib64/libc.so.6+0x10d817)
>     #2 0x7f20b451fa6c in g_vasprintf (/lib64/libglib-2.0.so.0+0x93a6c)
>     #3 0x7f20b44f8cd0 in g_strdup_vprintf (/lib64/libglib-2.0.so.0+0x6ccd0)
>     #4 0x7f20b44f8d8c in g_strdup_printf (/lib64/libglib-2.0.so.0+0x6cd8c)
>     #5 0x56413406fc86 in error_setv /mnt/sdb/backup/qemu/util/error.c:65
>     #6 0x564134070464 in error_setg_errno_internal /mnt/sdb/backup/qemu/util/error.c:109
>     #7 0x5641340851be in inet_connect_addr /mnt/sdb/backup/qemu/util/qemu-sockets.c:379
>     #8 0x5641340851be in inet_connect_saddr /mnt/sdb/backup/qemu/util/qemu-sockets.c:458
>     #9 0x5641340870ab in socket_connect /mnt/sdb/backup/qemu/util/qemu-sockets.c:1105
>     #10 0x564133eeaabf in qio_channel_socket_connect_sync /mnt/sdb/backup/qemu/io/channel-socket.c:145
>     #11 0x564133eeabf5 in qio_channel_socket_connect_worker /mnt/sdb/backup/qemu/io/channel-socket.c:168
>
> Reported-by: Euler Robot <euler.robot@huawei.com>
> Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>

Reviewed-by: Juan Quintela <quintela@redhat.com>

I am not sure that this are the only possible error cases, but they are
a step on the right direction.

Thanks, Juan.