Re: [Qemu-devel] [PATCH v2 1/1] blockjob: leak fix, remove from txn when failing early

[Jeff Cody <jcody@redhat.com>]

On Wed, Mar 28, 2018 at 04:28:05PM +0200, Marc-André Lureau wrote:
> On Wed, Mar 28, 2018 at 4:09 PM, Jeff Cody <jcody@redhat.com> wrote:
> > From: Marc-André Lureau <marcandre.lureau@redhat.com>
> >
> > This fixes leaks found by ASAN such as:
> >   GTESTER tests/test-blockjob
> > =================================================================
> > ==31442==ERROR: LeakSanitizer: detected memory leaks
> >
> > Direct leak of 24 byte(s) in 1 object(s) allocated from:
> >     #0 0x7f88483cba38 in __interceptor_calloc (/lib64/libasan.so.4+0xdea38)
> >     #1 0x7f8845e1bd77 in g_malloc0 ../glib/gmem.c:129
> >     #2 0x7f8845e1c04b in g_malloc0_n ../glib/gmem.c:360
> >     #3 0x5584d2732498 in block_job_txn_new /home/elmarco/src/qemu/blockjob.c:172
> >     #4 0x5584d2739b28 in block_job_create /home/elmarco/src/qemu/blockjob.c:973
> >     #5 0x5584d270ae31 in mk_job /home/elmarco/src/qemu/tests/test-blockjob.c:34
> >     #6 0x5584d270b1c1 in do_test_id /home/elmarco/src/qemu/tests/test-blockjob.c:57
> >     #7 0x5584d270b65c in test_job_ids /home/elmarco/src/qemu/tests/test-blockjob.c:118
> >     #8 0x7f8845e40b69 in test_case_run ../glib/gtestutils.c:2255
> >     #9 0x7f8845e40f29 in g_test_run_suite_internal ../glib/gtestutils.c:2339
> >     #10 0x7f8845e40fd2 in g_test_run_suite_internal ../glib/gtestutils.c:2351
> >     #11 0x7f8845e411e9 in g_test_run_suite ../glib/gtestutils.c:2426
> >     #12 0x7f8845e3fe72 in g_test_run ../glib/gtestutils.c:1692
> >     #13 0x5584d270d6e2 in main /home/elmarco/src/qemu/tests/test-blockjob.c:377
> >     #14 0x7f8843641f29 in __libc_start_main (/lib64/libc.so.6+0x20f29)
> >
> > Add an assert to make sure that the job doesn't have associated txn before free().
> >
> > [Jeff Cody: N.B., used updated patch provided by John Snow]
> 
> Looks good to me, so :)
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> thanks

Thanks,

Applied to my block branch:

git://github.com/codyprime/qemu-kvm-jtc block

-Jeff

> 
> >
> > ---
> >  blockjob.c | 14 ++++++++++++--
> >  1 file changed, 12 insertions(+), 2 deletions(-)
> >
> > diff --git a/blockjob.c b/blockjob.c
> > index ef3ed69ff1..c510a9fde5 100644
> > --- a/blockjob.c
> > +++ b/blockjob.c
> > @@ -204,6 +204,15 @@ void block_job_txn_add_job(BlockJobTxn *txn, BlockJob *job)
> >      block_job_txn_ref(txn);
> >  }
> >
> > +static void block_job_txn_del_job(BlockJob *job)
> > +{
> > +    if (job->txn) {
> > +        QLIST_REMOVE(job, txn_list);
> > +        block_job_txn_unref(job->txn);
> > +        job->txn = NULL;
> > +    }
> > +}
> > +
> >  static void block_job_pause(BlockJob *job)
> >  {
> >      job->pause_count++;
> > @@ -232,6 +241,7 @@ void block_job_unref(BlockJob *job)
> >  {
> >      if (--job->refcnt == 0) {
> >          assert(job->status == BLOCK_JOB_STATUS_NULL);
> > +        assert(!job->txn);
> >          BlockDriverState *bs = blk_bs(job->blk);
> >          QLIST_REMOVE(job, job_list);
> >          bs->job = NULL;
> > @@ -392,6 +402,7 @@ static void block_job_decommission(BlockJob *job)
> >      job->busy = false;
> >      job->paused = false;
> >      job->deferred_to_main_loop = true;
> > +    block_job_txn_del_job(job);
> >      block_job_state_transition(job, BLOCK_JOB_STATUS_NULL);
> >      block_job_unref(job);
> >  }
> > @@ -481,8 +492,7 @@ static int block_job_finalize_single(BlockJob *job)
> >          }
> >      }
> >
> > -    QLIST_REMOVE(job, txn_list);
> > -    block_job_txn_unref(job->txn);
> > +    block_job_txn_del_job(job);
> >      block_job_conclude(job);
> >      return 0;
> >  }
> > --
> > 2.13.6
> >