This is a note to let you know that I've just added the patch titled staging: media: tegra-video: fix device_node use after free to the 6.0-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: staging-media-tegra-video-fix-device_node-use-after-free.patch and it can be found in the queue-6.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c4d344163c3a7f90712525f931a6c016bbb35e18 Mon Sep 17 00:00:00 2001 From: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx> Date: Wed, 2 Nov 2022 12:01:02 +0100 Subject: staging: media: tegra-video: fix device_node use after free From: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx> commit c4d344163c3a7f90712525f931a6c016bbb35e18 upstream. At probe time this code path is followed: * tegra_csi_init * tegra_csi_channels_alloc * for_each_child_of_node(node, channel) -- iterates over channels * automatically gets 'channel' * tegra_csi_channel_alloc() * saves into chan->of_node a pointer to the channel OF node * automatically gets and puts 'channel' * now the node saved in chan->of_node has refcount 0, can disappear * tegra_csi_channels_init * iterates over channels * tegra_csi_channel_init -- uses chan->of_node After that, chan->of_node keeps storing the node until the device is removed. of_node_get() the node and of_node_put() it during teardown to avoid any risk. Fixes: 1ebaeb09830f ("media: tegra-video: Add support for external sensor capture") Cc: stable@xxxxxxxxxxxxxxx Cc: Sowjanya Komatineni <skomatineni@xxxxxxxxxx> Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/media/tegra-video/csi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/staging/media/tegra-video/csi.c +++ b/drivers/staging/media/tegra-video/csi.c @@ -433,7 +433,7 @@ static int tegra_csi_channel_alloc(struc for (i = 0; i < chan->numgangports; i++) chan->csi_port_nums[i] = port_num + i * CSI_PORTS_PER_BRICK; - chan->of_node = node; + chan->of_node = of_node_get(node); chan->numpads = num_pads; if (num_pads & 0x2) { chan->pads[0].flags = MEDIA_PAD_FL_SINK; @@ -641,6 +641,7 @@ static void tegra_csi_channels_cleanup(s media_entity_cleanup(&subdev->entity); } + of_node_put(chan->of_node); list_del(&chan->list); kfree(chan); } Patches currently in stable-queue which might be from luca.ceresoli@xxxxxxxxxxx are queue-6.0/staging-media-tegra-video-fix-device_node-use-after-free.patch queue-6.0/staging-media-tegra-video-fix-chan-mipi-value-on-error.patch