nvme-pci: use sgls for all user requests if possible

[ Upstream commit 6fad84a4d624c300d03ebba457cc641765050c43 ]

If the device supports SGLs, use these for all user requests. This
format encodes the expected transfer length so it can catch short buffer
errors in a user command, whether it occurred accidently or maliciously.

For controllers that support SGL data mode, this is a viable mitigation
to CVE-2023-6238. For controllers that don't support SGLs, log a warning
in the passthrough path since not having the capability can corrupt
data if the interface is not used correctly.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Stable-dep-of: 00817f0f1c45 ("nvme-ioctl: fix leaked requests on mapping error")
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Keith Busch
2024-11-08 15:41:08 -08:00
committed by Greg Kroah-Hartman
parent 595a5b23eb
commit 3c63fb6ef7
2 changed files with 13 additions and 4 deletions

View File

@@ -120,12 +120,20 @@ static int nvme_map_user_request(struct request *req, u64 ubuffer,
struct nvme_ns *ns = q->queuedata;
struct block_device *bdev = ns ? ns->disk->part0 : NULL;
bool supports_metadata = bdev && blk_get_integrity(bdev->bd_disk);
struct nvme_ctrl *ctrl = nvme_req(req)->ctrl;
bool has_metadata = meta_buffer && meta_len;
struct bio *bio = NULL;
int ret;
if (has_metadata && !supports_metadata)
return -EINVAL;
if (!nvme_ctrl_sgl_supported(ctrl))
dev_warn_once(ctrl->device, "using unchecked data buffer\n");
if (has_metadata) {
if (!supports_metadata)
return -EINVAL;
if (!nvme_ctrl_meta_sgl_supported(ctrl))
dev_warn_once(ctrl->device,
"using unchecked metadata buffer\n");
}
if (ioucmd && (ioucmd->flags & IORING_URING_CMD_FIXED)) {
struct iov_iter iter;

View File

@@ -514,7 +514,8 @@ static inline bool nvme_pci_metadata_use_sgls(struct nvme_dev *dev,
{
if (!nvme_ctrl_meta_sgl_supported(&dev->ctrl))
return false;
return req->nr_integrity_segments > 1;
return req->nr_integrity_segments > 1 ||
nvme_req(req)->flags & NVME_REQ_USERCMD;
}
static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req,
@@ -532,7 +533,7 @@ static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req,
if (nvme_pci_metadata_use_sgls(dev, req))
return true;
if (!sgl_threshold || avg_seg_size < sgl_threshold)
return false;
return nvme_req(req)->flags & NVME_REQ_USERCMD;
return true;
}