From: Nuno Sá Date: Fri, 15 Jul 2022 12:28:49 +0000 (+0200) Subject: iio: inkern: only release the device node when done with it X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=79c3e84874c7d14f04ad58313b64955a0d2e9437;p=linux.git iio: inkern: only release the device node when done with it 'of_node_put()' can potentially release the memory pointed to by 'iiospec.np' which would leave us with an invalid pointer (and we would still pass it in 'of_xlate()'). Note that it is not guaranteed for the of_node lifespan to be attached to the device (to which is attached) lifespan so that there is (even though very unlikely) the possibility for the node to be freed while the device is still around. Thus, as there are indeed some of_xlate users which do access the node, a race is indeed possible. As such, we can only release the node after we are done with it. Fixes: 17d82b47a215d ("iio: Add OF support") Signed-off-by: Nuno Sá Link: https://lore.kernel.org/r/20220715122903.332535-2-nuno.sa@analog.com Signed-off-by: Jonathan Cameron --- diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c index df74765d33dcb..9d87057794fca 100644 --- a/drivers/iio/inkern.c +++ b/drivers/iio/inkern.c @@ -165,9 +165,10 @@ static int __of_iio_channel_get(struct iio_channel *channel, idev = bus_find_device(&iio_bus_type, NULL, iiospec.np, iio_dev_node_match); - of_node_put(iiospec.np); - if (idev == NULL) + if (idev == NULL) { + of_node_put(iiospec.np); return -EPROBE_DEFER; + } indio_dev = dev_to_iio_dev(idev); channel->indio_dev = indio_dev; @@ -175,6 +176,7 @@ static int __of_iio_channel_get(struct iio_channel *channel, index = indio_dev->info->of_xlate(indio_dev, &iiospec); else index = __of_iio_simple_xlate(indio_dev, &iiospec); + of_node_put(iiospec.np); if (index < 0) goto err_put; channel->channel = &indio_dev->channels[index];