Patch "nvme-tcp: don't access released socket during error recovery" has been added to the 6.2-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

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

    nvme-tcp: don't access released socket during error recovery

to the 6.2-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:
     nvme-tcp-don-t-access-released-socket-during-error-r.patch
and it can be found in the queue-6.2 subdirectory.

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



commit 5597b1b0d533229afffb3c69f527626afb7889b1
Author: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Date:   Sun Feb 26 21:42:54 2023 +0900

    nvme-tcp: don't access released socket during error recovery
    
    [ Upstream commit 76d54bf20cdcc1ed7569a89885e09636e9a8d71d ]
    
    While the error recovery work is temporarily failing reconnect attempts,
    running the 'nvme list' command causes a kernel NULL pointer dereference
    by calling getsockname() with a released socket.
    
    During error recovery work, the nvme tcp socket is released and a new one
    created, so it is not safe to access the socket without proper check.
    
    Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
    Fixes: 02c57a82c008 ("nvme-tcp: print actual source IP address through sysfs "address" attr")
    Reviewed-by: Martin Belanger <martin.belanger@xxxxxxxx>
    Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
    Signed-off-by: Christoph Hellwig <hch@xxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 8cedc1ef496c7..1ca52ac163c2f 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -2486,6 +2486,10 @@ static int nvme_tcp_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
 
 	len = nvmf_get_address(ctrl, buf, size);
 
+	mutex_lock(&queue->queue_lock);
+
+	if (!test_bit(NVME_TCP_Q_LIVE, &queue->flags))
+		goto done;
 	ret = kernel_getsockname(queue->sock, (struct sockaddr *)&src_addr);
 	if (ret > 0) {
 		if (len > 0)
@@ -2493,6 +2497,8 @@ static int nvme_tcp_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
 		len += scnprintf(buf + len, size - len, "%ssrc_addr=%pISc\n",
 				(len) ? "," : "", &src_addr);
 	}
+done:
+	mutex_unlock(&queue->queue_lock);
 
 	return len;
 }