diff options
| author | Varun Prakash <varun@chelsio.com> | 2021-10-26 16:31:55 +0300 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2021-10-27 08:58:26 +0300 |
| commit | ce7723e9cdae4eb3030da082876580f4b2dc0861 (patch) | |
| tree | a5e1471acc87c1d2c157b04d2efe2658eb62a3f8 /drivers/nvme/host/tcp.c | |
| parent | 25e1f67eda4a19c91dc05c84d6d413c53efb447b (diff) | |
| download | linux-ce7723e9cdae4eb3030da082876580f4b2dc0861.tar.xz | |
nvme-tcp: fix possible req->offset corruption
With commit db5ad6b7f8cd ("nvme-tcp: try to send request in queue_rq
context") r2t and response PDU can get processed while send function
is executing.
Current data digest send code uses req->offset after kernel_sendmsg(),
this creates a race condition where req->offset gets reset before it
is used in send function.
This can happen in two cases -
1. Target sends r2t PDU which resets req->offset.
2. Target send response PDU which completes the req and then req is
used for a new command, nvme_tcp_setup_cmd_pdu() resets req->offset.
Fix this by storing req->offset in a local variable and using
this local variable after kernel_sendmsg().
Fixes: db5ad6b7f8cd ("nvme-tcp: try to send request in queue_rq context")
Signed-off-by: Varun Prakash <varun@chelsio.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers/nvme/host/tcp.c')
| -rw-r--r-- | drivers/nvme/host/tcp.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 0626d14e6d4c..1a209f0d7181 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -1050,6 +1050,7 @@ static int nvme_tcp_try_send_data_pdu(struct nvme_tcp_request *req) static int nvme_tcp_try_send_ddgst(struct nvme_tcp_request *req) { struct nvme_tcp_queue *queue = req->queue; + size_t offset = req->offset; int ret; struct msghdr msg = { .msg_flags = MSG_DONTWAIT }; struct kvec iov = { @@ -1066,7 +1067,7 @@ static int nvme_tcp_try_send_ddgst(struct nvme_tcp_request *req) if (unlikely(ret <= 0)) return ret; - if (req->offset + ret == NVME_TCP_DIGEST_LENGTH) { + if (offset + ret == NVME_TCP_DIGEST_LENGTH) { nvme_tcp_done_send_req(queue); return 1; } |