From: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
[ Upstream commit 6173a77b7e9d3e202bdb9897b23f2a8afe7bf286 ]
An nvme target ->queue_response() operation implementation may free the
request passed as argument. Such implementation potentially could result
in a use after free of the request pointer when percpu_ref_put() is
called in nvmet_req_complete().
Avoid such problem by using a local variable to save the sq pointer
before calling __nvmet_req_complete(), thus avoiding dereferencing the
req pointer after that function call.
Fixes: a07b4970f464 ("nvmet: add a generic NVMe target")
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/nvme/target/core.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index f66ed13d7c11d..3935165048e74 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -756,8 +756,10 @@ static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
void nvmet_req_complete(struct nvmet_req *req, u16 status)
{
+ struct nvmet_sq *sq = req->sq;
+
__nvmet_req_complete(req, status);
- percpu_ref_put(&req->sq->ref);
+ percpu_ref_put(&sq->ref);
}
EXPORT_SYMBOL_GPL(nvmet_req_complete);
--
2.39.2
