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

[Marc-André Lureau]

On Wed, Mar 28, 2018 at 4:09 PM, Jeff Cody <address@hidden> wrote:
> From: Marc-André Lureau <address@hidden>
>
> 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 <address@hidden>

thanks

>
> ---
>  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
>