[PATCH] spi: ti-qspi: fix use-after-free after DMA setup failure

[PATCH] spi: ti-qspi: fix use-after-free after DMA setup failure

[Johan Hovold]

The driver falls back to PIO mode if DMA setup fails during probe.

Make sure to clear the DMA channel pointer also if buffer allocation
fails to avoid passing a pointer to the released channel to the DMA
engine (or trying to free the channel a second time on late probe errors
or driver unbind).

This issue was flagged by Sashiko when reviewing a devres allocation
conversion patch.

Fixes: c687c46e9e45 ("spi: spi-ti-qspi: Use bounce buffer if read buffer is not DMA'ble")
Link: https://sashiko.dev/#/patchset/20260505072909.618363-1-johan%40kernel.org?part=17
Cc: stable@vger.kernel.org	# 4.12
Cc: Vignesh R <vigneshr@ti.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/spi/spi-ti-qspi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c
index 1fbd710d616f..e3b413b9828c 100644
--- a/drivers/spi/spi-ti-qspi.c
+++ b/drivers/spi/spi-ti-qspi.c
@@ -867,6 +867,7 @@ static int ti_qspi_probe(struct platform_device *pdev)
 		dev_err(qspi->dev,
 			"dma_alloc_coherent failed, using PIO mode\n");
 		dma_release_channel(qspi->rx_chan);
+		qspi->rx_chan = NULL;
 		goto no_dma;
 	}
 	host->dma_rx = qspi->rx_chan;
-- 
2.53.0

Re: [PATCH] spi: ti-qspi: fix use-after-free after DMA setup failure

[Mark Brown]

On Tue, 12 May 2026 09:48:09 +0200, Johan Hovold wrote:
> spi: ti-qspi: fix use-after-free after DMA setup failure

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-7.1

Thanks!

[1/1] spi: ti-qspi: fix use-after-free after DMA setup failure
      https://git.kernel.org/broonie/spi/c/ea6ec3343e05

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark