Ensures that qmp_backup_cancel doesn't pick a job that's already been freed. With unlucky timings it seems possible that: 1. job_exit -> job_completed -> job_finalize_single starts 2. pvebackup_co_complete_stream gets spawned in completion callback 3. job finalize_single finishes -> job's refcount hits zero -> job is freed 4. qmp_backup_cancel comes in and locks backup_state.backup_mutex before pvebackup_co_complete_stream can remove the job from the di_list 5. qmp_backup_cancel will pick a job that's already been freed
Signed-off-by: Fabian Ebner <[email protected]> --- New in v2. pve-backup.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/pve-backup.c b/pve-backup.c index dfaf4c93f8..3cede98b1d 100644 --- a/pve-backup.c +++ b/pve-backup.c @@ -314,6 +314,11 @@ static void coroutine_fn pvebackup_co_complete_stream(void *opaque) } } + if (di->job) { + job_unref(&di->job->job); + di->job = NULL; + } + // remove self from job list backup_state.di_list = g_list_remove(backup_state.di_list, di); @@ -497,6 +502,9 @@ static void create_backup_jobs_bh(void *opaque) { aio_context_release(aio_context); di->job = job; + if (job) { + job_ref(&job->job); + } if (!job || local_err) { error_setg(errp, "backup_job_create failed: %s", @@ -531,6 +539,11 @@ static void create_backup_jobs_bh(void *opaque) { aio_context_release(ctx); canceled = true; } + + if (di->job) { + job_unref(&di->job->job); + di->job = NULL; + } } } -- 2.30.2 _______________________________________________ pve-devel mailing list [email protected] https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
