74 lines
2.5 KiB
Diff
74 lines
2.5 KiB
Diff
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
|
|
From: Fabian Ebner <f.ebner@proxmox.com>
|
|
Date: Wed, 25 May 2022 13:59:38 +0200
|
|
Subject: [PATCH] PVE-Backup: ensure jobs in di_list are referenced
|
|
|
|
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: Fiona Ebner <f.ebner@proxmox.com>
|
|
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
|
|
[FE: adapt for new job lock mechanism replacing AioContext locks]
|
|
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
|
|
---
|
|
pve-backup.c | 22 +++++++++++++++++++---
|
|
1 file changed, 19 insertions(+), 3 deletions(-)
|
|
|
|
diff --git a/pve-backup.c b/pve-backup.c
|
|
index 79d14d6a0b..67e2b99d74 100644
|
|
--- a/pve-backup.c
|
|
+++ b/pve-backup.c
|
|
@@ -318,6 +318,13 @@ static void coroutine_fn pvebackup_co_complete_stream(void *opaque)
|
|
}
|
|
}
|
|
|
|
+ if (di->job) {
|
|
+ WITH_JOB_LOCK_GUARD() {
|
|
+ job_unref_locked(&di->job->job);
|
|
+ di->job = NULL;
|
|
+ }
|
|
+ }
|
|
+
|
|
// remove self from job list
|
|
backup_state.di_list = g_list_remove(backup_state.di_list, di);
|
|
|
|
@@ -493,6 +500,11 @@ static void create_backup_jobs_bh(void *opaque) {
|
|
aio_context_release(aio_context);
|
|
|
|
di->job = job;
|
|
+ if (job) {
|
|
+ WITH_JOB_LOCK_GUARD() {
|
|
+ job_ref_locked(&job->job);
|
|
+ }
|
|
+ }
|
|
|
|
if (!job || local_err) {
|
|
error_setg(errp, "backup_job_create failed: %s",
|
|
@@ -520,11 +532,15 @@ static void create_backup_jobs_bh(void *opaque) {
|
|
di->target = NULL;
|
|
}
|
|
|
|
- if (!canceled && di->job) {
|
|
+ if (di->job) {
|
|
WITH_JOB_LOCK_GUARD() {
|
|
- job_cancel_sync_locked(&di->job->job, true);
|
|
+ if (!canceled) {
|
|
+ job_cancel_sync_locked(&di->job->job, true);
|
|
+ canceled = true;
|
|
+ }
|
|
+ job_unref_locked(&di->job->job);
|
|
+ di->job = NULL;
|
|
}
|
|
- canceled = true;
|
|
}
|
|
}
|
|
}
|