From: weiping zhang <zhangweiping@didichuxing.com>
Date: Fri, 25 Aug 2017 23:49:32 +0800
Subject: [PATCH] blkcg: avoid free blkcg_root when failed to alloc blkcg
Git-commit: 4c18c9e962eb02e23731e5b40d4474fb04fdcb23
Patch-mainline: v4.14-rc1
References: bsc#1104967,FATE#325924
policy
this patch fix two errors, firstly avoid kfree blk_root, secondly not
free(blkcg) ,if blkcg alloc fail(blkcg == NULL), just unlock that mutex;
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
block/blk-cgroup.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 0480892e97e5..d3f56baee936 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1067,7 +1067,7 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css)
blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL);
if (!blkcg) {
ret = ERR_PTR(-ENOMEM);
- goto free_blkcg;
+ goto unlock;
}
}
@@ -1111,8 +1111,10 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css)
for (i--; i >= 0; i--)
if (blkcg->cpd[i])
blkcg_policy[i]->cpd_free_fn(blkcg->cpd[i]);
-free_blkcg:
- kfree(blkcg);
+
+ if (blkcg != &blkcg_root)
+ kfree(blkcg);
+unlock:
mutex_unlock(&blkcg_pol_mutex);
return ret;
}
--
2.16.4