diff options
author | Hongbo Yao <yaohongbo@huawei.com> | 2019-01-07 10:22:07 +0800 |
---|---|---|
committer | Christoph Hellwig <hch@lst.de> | 2019-01-09 13:47:05 -0500 |
commit | dcca1662727220d18fa351097ddff33f95f516c5 (patch) | |
tree | f2c10b033b953198237cc513edf5d73df9aff69b | |
parent | 8fae268b40f5191227ae7050a99cb2cf1b914ddd (diff) |
nvme-pci: fix out of bounds access in nvme_cqe_pending
There is an out of bounds array access in nvme_cqe_peding().
When enable irq_thread for nvme interrupt, there is racing between the
nvmeq->cq_head updating and reading.
nvmeq->cq_head is updated in nvme_update_cq_head(), if nvmeq->cq_head
equals nvmeq->q_depth and before its value set to zero, nvme_cqe_pending()
uses its value as an array index, the index will be out of bounds.
Signed-off-by: Hongbo Yao <yaohongbo@huawei.com>
[hch: slight coding style update]
Signed-off-by: Christoph Hellwig <hch@lst.de>
-rw-r--r-- | drivers/nvme/host/pci.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index f891eb57f263..3f53a2c3042d 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1020,9 +1020,11 @@ static void nvme_complete_cqes(struct nvme_queue *nvmeq, u16 start, u16 end) static inline void nvme_update_cq_head(struct nvme_queue *nvmeq) { - if (++nvmeq->cq_head == nvmeq->q_depth) { + if (nvmeq->cq_head == nvmeq->q_depth - 1) { nvmeq->cq_head = 0; nvmeq->cq_phase = !nvmeq->cq_phase; + } else { + nvmeq->cq_head++; } } |