This is a note to let you know that I've just added the patch titled spi: spi-fsl-lpspi: Adjust type of scldiv to the 6.12-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: spi-spi-fsl-lpspi-adjust-type-of-scldiv.patch and it can be found in the queue-6.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e35e04827a85f31d3bd754ad7410df6b86612358 Author: Stefan Wahren <wahrenst@xxxxxxx> Date: Mon Sep 30 11:30:54 2024 +0200 spi: spi-fsl-lpspi: Adjust type of scldiv [ Upstream commit fa8ecda9876ac1e7b29257aa82af1fd0695496e2 ] The target value of scldiv is just a byte, but its calculation in fsl_lpspi_set_bitrate could be negative. So use an adequate type to store the result and avoid overflows. After that this needs range check adjustments, but this should make the code less opaque. Signed-off-by: Stefan Wahren <wahrenst@xxxxxxx> Reviewed-by: Frank Li <Frank.Li@xxxxxxx> Link: https://patch.msgid.link/20240930093056.93418-2-wahrenst@xxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c index 9573b8fa4fbfc..29b9676fe43d8 100644 --- a/drivers/spi/spi-fsl-lpspi.c +++ b/drivers/spi/spi-fsl-lpspi.c @@ -315,9 +315,10 @@ static void fsl_lpspi_set_watermark(struct fsl_lpspi_data *fsl_lpspi) static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi) { struct lpspi_config config = fsl_lpspi->config; - unsigned int perclk_rate, scldiv, div; + unsigned int perclk_rate, div; u8 prescale_max; u8 prescale; + int scldiv; perclk_rate = clk_get_rate(fsl_lpspi->clk_per); prescale_max = fsl_lpspi->devtype_data->prescale_max; @@ -338,13 +339,13 @@ static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi) for (prescale = 0; prescale <= prescale_max; prescale++) { scldiv = div / (1 << prescale) - 2; - if (scldiv < 256) { + if (scldiv >= 0 && scldiv < 256) { fsl_lpspi->config.prescale = prescale; break; } } - if (scldiv >= 256) + if (scldiv < 0 || scldiv >= 256) return -EINVAL; writel(scldiv | (scldiv << 8) | ((scldiv >> 1) << 16),