Patch "nvmet-rdma: Fix a possible uninitialized variable dereference" has been added to the 4.9-stable tree

Patch "nvmet-rdma: Fix a possible uninitialized variable dereference" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    nvmet-rdma: Fix a possible uninitialized variable dereference

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nvmet-rdma-fix-a-possible-uninitialized-variable-dereference.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Mon Dec 18 14:12:34 CET 2017
From: Sagi Grimberg <sagi@grimberg.me>
Date: Thu, 9 Mar 2017 13:45:52 +0200
Subject: nvmet-rdma: Fix a possible uninitialized variable dereference

From: Sagi Grimberg <sagi@grimberg.me>


[ Upstream commit b25634e2a051bef4b2524b11adddfbfa6448f6cd ]

When handling a new recv command, we grab a new rsp resource and
check for the queue state being live. In case the queue is not in
live state, we simply restore the rsp back to the free list. However
in this flow we didn't set rsp->queue yet, so we cannot dereference it.

Instead, make sure to initialize rsp->queue (and other rsp members)
as soon as possible so we won't reference uninitialized variables.

Reported-by: Yi Zhang <yizhan@redhat.com>
Reported-by: Raju Rangoju <rajur@chelsio.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/nvme/target/rdma.c |    8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -703,11 +703,6 @@ static void nvmet_rdma_handle_command(st
 {
 	u16 status;
 
-	cmd->queue = queue;
-	cmd->n_rdma = 0;
-	cmd->req.port = queue->port;
-
-
 	ib_dma_sync_single_for_cpu(queue->dev->device,
 		cmd->cmd->sge[0].addr, cmd->cmd->sge[0].length,
 		DMA_FROM_DEVICE);
@@ -760,9 +755,12 @@ static void nvmet_rdma_recv_done(struct
 
 	cmd->queue = queue;
 	rsp = nvmet_rdma_get_rsp(queue);
+	rsp->queue = queue;
 	rsp->cmd = cmd;
 	rsp->flags = 0;
 	rsp->req.cmd = cmd->nvme_cmd;
+	rsp->req.port = queue->port;
+	rsp->n_rdma = 0;
 
 	if (unlikely(queue->state != NVMET_RDMA_Q_LIVE)) {
 		unsigned long flags;


Patches currently in stable-queue which might be from sagi@grimberg.me are

queue-4.9/blk-mq-fix-tagset-reinit-in-the-presence-of-cpu-hot-unplug.patch
queue-4.9/nvmet-confirm-sq-percpu-has-scheduled-and-switched-to-atomic.patch
queue-4.9/nvme-use-kref_get_unless_zero-in-nvme_find_get_ns.patch
queue-4.9/nvme-loop-fix-a-possible-use-after-free-when-destroying-the-admin-queue.patch
queue-4.9/nvmet-rdma-fix-a-possible-uninitialized-variable-dereference.patch