From 1bf86336e4b6cf40873fda47a7fe191446864937 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Tue, 19 May 2026 13:01:57 -0700 Subject: [PATCH] nvme-pci: fix dma mapping leak on data setup error We're leaking the initial DMA mapping during iteration if we fail to allocate the tracking descriptor for both PRP and SGL. Unmap the iterator directly; we can't use the existing unmap helper because it depends on the tracking descriptor being successfully allocated, so a new one for an in-use iterator is provided. The mappings were also leaking when the driver detects an invalid bio_vec when mapping PRPs, so fix that too. Fixes: b8b7570a7ec87 ("nvme-pci: fix dma unmapping when using PRPs and not using the IOVA mapping") Fixes: 7ce3c1dd78fca ("nvme-pci: convert the data mapping to blk_rq_dma_map") Reviewed-by: Christoph Hellwig Signed-off-by: Keith Busch --- drivers/nvme/host/pci.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index f423f1718439..b5f846200678 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -997,6 +997,23 @@ static bool nvme_pci_prp_iter_next(struct request *req, struct device *dma_dev, return nvme_pci_prp_save_mapping(req, dma_dev, iter); } +static void nvme_unmap_iter(struct request *req, struct blk_dma_iter *iter, + struct dma_iova_state *state) +{ + struct nvme_queue *nvmeq = req->mq_hctx->driver_data; + struct device *dev = nvmeq->dev->dev; + + if (!blk_rq_dma_unmap(req, dev, state, iter->len, iter->p2pdma.map)) { + unsigned int attrs = 0; + + if (iter->p2pdma.map == PCI_P2PDMA_MAP_THRU_HOST_BRIDGE) + attrs |= DMA_ATTR_MMIO; + + dma_unmap_phys(dev, iter->addr, iter->len, rq_dma_dir(req), + attrs); + } +} + static blk_status_t nvme_pci_setup_data_prp(struct request *req, struct blk_dma_iter *iter) { @@ -1007,8 +1024,10 @@ static blk_status_t nvme_pci_setup_data_prp(struct request *req, unsigned int prp_len, i; __le64 *prp_list; - if (!nvme_pci_prp_save_mapping(req, nvmeq->dev->dev, iter)) + if (!nvme_pci_prp_save_mapping(req, nvmeq->dev->dev, iter)) { + nvme_unmap_iter(req, iter, &iod->dma_state); return iter->status; + } /* * PRP1 always points to the start of the DMA transfers. @@ -1113,6 +1132,7 @@ static blk_status_t nvme_pci_setup_data_prp(struct request *req, dev_err_once(nvmeq->dev->dev, "Incorrectly formed request for payload:%d nents:%d\n", blk_rq_payload_bytes(req), blk_rq_nr_phys_segments(req)); + nvme_unmap_data(req); return BLK_STS_IOERR; } @@ -1156,8 +1176,11 @@ static blk_status_t nvme_pci_setup_data_sgl(struct request *req, sg_list = dma_pool_alloc(nvme_dma_pool(nvmeq, iod), GFP_ATOMIC, &sgl_dma); - if (!sg_list) + if (!sg_list) { + nvme_unmap_iter(req, iter, &iod->dma_state); return BLK_STS_RESOURCE; + } + iod->descriptors[iod->nr_descriptors++] = sg_list; do { @@ -1314,8 +1337,10 @@ static blk_status_t nvme_pci_setup_meta_iter(struct request *req) sg_list = dma_pool_alloc(nvmeq->descriptor_pools.small, GFP_ATOMIC, &sgl_dma); - if (!sg_list) + if (!sg_list) { + nvme_unmap_iter(req, &iter, &iod->meta_dma_state); return BLK_STS_RESOURCE; + } iod->meta_descriptor = sg_list; iod->meta_dma = sgl_dma;