6.12-stable review patch. If anyone has any objections, please let me know.
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From: Caleb Sander Mateos csander@purestorage.com
[ Upstream commit 578539e0969028f711c34d9a4565931edfe1d730 ]
nvme_tcp_init_connection() attempts to receive an ICResp PDU but only checks that the return value from recvmsg() is non-negative. If the sender closes the TCP connection or sends fewer than 128 bytes, this check will pass even though the full PDU wasn't received.
Ensure the full ICResp PDU is received by checking that recvmsg() returns the expected 128 bytes.
Additionally set the MSG_WAITALL flag for recvmsg(), as a sender could split the ICResp over multiple TCP frames. Without MSG_WAITALL, recvmsg() could return prematurely with only part of the PDU.
Fixes: 3f2304f8c6d6 ("nvme-tcp: add NVMe over TCP host driver") Signed-off-by: Caleb Sander Mateos csander@purestorage.com Reviewed-by: Sagi Grimberg sagi@grimberg.me Reviewed-by: Hannes Reinecke hare@suse.de Signed-off-by: Keith Busch kbusch@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/tcp.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 34eb3dabdc8a6..840ae475074d0 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -1449,11 +1449,14 @@ static int nvme_tcp_init_connection(struct nvme_tcp_queue *queue) msg.msg_control = cbuf; msg.msg_controllen = sizeof(cbuf); } + msg.msg_flags = MSG_WAITALL; ret = kernel_recvmsg(queue->sock, &msg, &iov, 1, iov.iov_len, msg.msg_flags); - if (ret < 0) { + if (ret < sizeof(*icresp)) { pr_warn("queue %d: failed to receive icresp, error %d\n", nvme_tcp_queue_id(queue), ret); + if (ret >= 0) + ret = -ECONNRESET; goto free_icresp; } ret = -ENOTCONN;