[PATCH 5.15 050/201] nvme: fix block device naming collision

Greg Kroah-Hartman
2022-07-27T17:05:36Z

From: Israel Rukshin <israelr@nvidia.com>

[ Upstream commit 6961b5e02876b3b47f030a1f1ee8fd3e631ac270 ]

The issue exists when multipath is enabled and the namespace is
shared, but all the other controller checks at nvme_is_unique_nsid()
are false. The reason for this issue is that nvme_is_unique_nsid()
returns false when is called from nvme_mpath_alloc_disk() due to an
uninitialized value of head->shared. The patch fixes it by setting
head->shared before nvme_mpath_alloc_disk() is called.

Fixes: 5974ea7ce0f9 ("nvme: allow duplicate NSIDs for private namespaces")
Signed-off-by: Israel Rukshin <israelr@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/nvme/host/core.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 8fca84d44446..0c9cdbaf5cd6 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -3660,7 +3660,7 @@ static int nvme_add_ns_cdev(struct nvme_ns *ns)
}

static struct nvme_ns_head *nvme_alloc_ns_head(struct nvme_ctrl *ctrl,
- unsigned nsid, struct nvme_ns_ids *ids)
+ unsigned nsid, struct nvme_ns_ids *ids, bool is_shared)
{
struct nvme_ns_head *head;
size_t size = sizeof(*head);
@@ -3684,6 +3684,7 @@ static struct nvme_ns_head *nvme_alloc_ns_head(struct nvme_ctrl *ctrl,
head->subsys = ctrl->subsys;
head->ns_id = nsid;
head->ids = *ids;
+ head->shared = is_shared;
kref_init(&head->ref);

if (head->ids.csi) {
@@ -3730,12 +3731,11 @@ static int nvme_init_ns_head(struct nvme_ns *ns, unsigned nsid,
"duplicate IDs for nsid %d\n", nsid);
goto out_unlock;
}
- head = nvme_alloc_ns_head(ctrl, nsid, ids);
+ head = nvme_alloc_ns_head(ctrl, nsid, ids, is_shared);
if (IS_ERR(head)) {
ret = PTR_ERR(head);
goto out_unlock;
}
- head->shared = is_shared;
} else {
ret = -EINVAL;
if (!is_shared || !head->shared) {
--
2.35.1