From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37897) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dIDvy-0000kX-U2 for qemu-devel@nongnu.org; Tue, 06 Jun 2017 08:50:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dIDvy-00025V-13 for qemu-devel@nongnu.org; Tue, 06 Jun 2017 08:50:07 -0400 Date: Tue, 6 Jun 2017 14:49:53 +0200 From: Kevin Wolf Message-ID: <20170606124953.GD5448@noname.redhat.com> References: <20170606052438.35405-1-haoqf@linux.vnet.ibm.com> <20170606052438.35405-2-haoqf@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170606052438.35405-2-haoqf@linux.vnet.ibm.com> Subject: Re: [Qemu-devel] [PATCH v2 1/1] qemu/migration: fix the double free problem on from_src_file List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: QingFeng Hao Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, peterx@redhat.com, dgilbert@redhat.com, borntraeger@de.ibm.com, cornelia.huck@de.ibm.com, liujbjl@linux.vnet.ibm.com, famz@redhat.com Am 06.06.2017 um 07:24 hat QingFeng Hao geschrieben: > In load_snapshot, mis->from_src_file is freed twice, the first free is by > qemu_fclose, the second is by migration_incoming_state_destroy and > it causes Illegal instruction exception. The fix is just to remove the > first free. > > This problem is found by qemu-iotests case 068 since commit > "660819b migration: shut src return path unconditionally". The error is: > 068 1s ... - output mismatch (see 068.out.bad) > --- tests/qemu-iotests/068.out 2017-05-06 01:00:26.417270437 +0200 > +++ 068.out.bad 2017-06-03 13:59:55.360274640 +0200 > @@ -6,6 +6,8 @@ > QEMU X.Y.Z monitor - type 'help' for more information > (qemu) savevm 0 > (qemu) quit > +./common.config: line 107: 242472 Illegal instruction (core dumped) ( if [ -n "${QEMU_NEED_PID}" ]; then > + echo $BASHPID > "${QEMU_TEST_DIR}/qemu-${_QEMU_HANDLE}.pid"; > +fi; exec "$QEMU_PROG" $QEMU_OPTIONS "$@" ) > QEMU X.Y.Z monitor - type 'help' for more information > -(qemu) quit > -*** done > +(qemu) *** done > > Signed-off-by: QingFeng Hao > Reviewed-by: Dr. David Alan Gilbert > Reviewed-by: Peter Xu Dave, as you only gave R-b rather than merging the patch, should this be merged through the block tree? > diff --git a/migration/savevm.c b/migration/savevm.c > index 9c320f59d0..853e14e34e 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -2290,7 +2290,6 @@ int load_snapshot(const char *name, Error **errp) > > aio_context_acquire(aio_context); > ret = qemu_loadvm_state(f); > - qemu_fclose(f); > aio_context_release(aio_context); > > migration_incoming_state_destroy(); Did we check other callers of migration_incoming_state_destroy()? For example, qmp_xen_load_devices_state() looks suspicious, too. I can't tell for postcopy_ram_listen_thread() - commit 660819b didn't seem to remove a qemu_fclose() call there, but I can't see one left behind either. Was the file leaked before commit 660819b or am I missing something? Kevin