Commit 58bb5081cba1 ("ASoC: SOF: Xtensa: dump ar registers to restore
call stack") added a shared Xtensa helper that iterates over a flexible
array of AR registers (`ar[]`) controlled by `plat_hdr.numaregs`.

While Intel IPC4 allocates dynamic storage for the AR block, the i.MX
IPC3 path reads the oops message into a stack-allocated struct without
backing storage for `ar[]`, while leaving `numaregs` unvalidated. This
causes a stack out-of-bounds read when printing a DSP panic.

Clear `numaregs` to 0 on i.MX since the AR block is not fetched or
supported on this platform, preventing unsafe out-of-bounds memory
accesses in the shared Xtensa helper.

Fixes: 58bb5081cba1 ("ASoC: SOF: Xtensa: dump ar registers to restore call stack")
Signed-off-by: Ștefan Ghețu <stefanghetu9@gmail.com>
---
 sound/soc/sof/imx/imx-common.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sound/soc/sof/imx/imx-common.c b/sound/soc/sof/imx/imx-common.c
index 7a03c8cc5dd4..436fe49246ba 100644
--- a/sound/soc/sof/imx/imx-common.c
+++ b/sound/soc/sof/imx/imx-common.c
@@ -34,6 +34,7 @@ void imx8_get_registers(struct snd_sof_dev *sdev,
 
 	/* first read registers */
 	sof_mailbox_read(sdev, offset, xoops, sizeof(*xoops));
+	xoops->plat_hdr.numaregs = 0;
 
 	/* then get panic info */
 	if (xoops->arch_hdr.totalsize > EXCEPT_MAX_HDR_SIZE) {
-- 
2.53.0

On Tue, 08 Sep 2026 20:07:40 +0300, Ștefan Ghețu wrote:
> ASoC: SOF: imx: Prevent stack OOB read in DSP panic dump

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-7.4

Thanks!

[1/1] ASoC: SOF: imx: Prevent stack OOB read in DSP panic dump
      https://git.kernel.org/broonie/sound/c/48ed992bfbe5

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.

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Thanks,
Mark