Re: [PATCH v1] i2c: qcom-geni: Clear stale TX/RX buffer pointers after GPI cleanup

[Wolfram Sang <wsa+renesas@sang-engineering.com>]

On Wed, Sep 02, 2026 at 08:15:13PM +0530, Aniket Randive wrote:
> The TX and RX buffer pointers are reused across messages in a GPI
> transfer. After a buffer is unmapped and freed, the pointer is left
> unchanged. A later message can reuse the stale pointer in the cleanup
> path, causing a double unmap and double free.
> 
> This can happen when a READ message is followed by a WRITE message,
> leaving a stale RX buffer pointer behind. A similar issue can occur for
> the TX buffer when a mapping or allocation failure prevents the pointer
> from being updated before the error path runs.
> 
> Clear tx_buf and rx_buf after unmapping and freeing them. This ensures
> later iterations and error paths only see a valid buffer pointer or
> NULL, preventing double unmap and double free issues.
> 
> Signed-off-by: Aniket Randive <aniket.randive@oss.qualcomm.com>

Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Applied to for-andi, but maybe this should go to i2c-fixes first?