From: Laibin Qiu qiulaibin@huawei.com
hulk inclusion category: bugfix bugzilla: 186352, https://gitee.com/openeuler/kernel/issues/I4YADX CVE: NA
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In case of BLK_MQ_F_BLOCKING, per-hctx srcu is used to protect dispatch critical area. But the current process is not aware when memory of srcu allocation failed in blk_mq_alloc_hctx, which will leads to illegal address BUG. Add return value validation to avoid this problem.
Signed-off-by: Laibin Qiu qiulaibin@huawei.com Reviewed-by: Hou Tao houtao1@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- block/blk-mq.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c index c3beaca1f4fb..9ae1663348ac 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2852,12 +2852,16 @@ blk_mq_alloc_hctx(struct request_queue *q, struct blk_mq_tag_set *set, if (!hctx->fq) goto free_bitmap;
- if (hctx->flags & BLK_MQ_F_BLOCKING) - init_srcu_struct(hctx->srcu); + if (hctx->flags & BLK_MQ_F_BLOCKING) { + if (init_srcu_struct(hctx->srcu) != 0) + goto free_flush_queue; + } blk_mq_hctx_kobj_init(hctx);
return hctx;
+ free_flush_queue: + blk_free_flush_queue(hctx->fq); free_bitmap: sbitmap_free(&hctx->ctx_map); free_ctxs: