From 0743acf746a81e0460a56fd5ff847d97fa7eb370 Mon Sep 17 00:00:00 2001 From: Mikhail Kshevetskiy Date: Sun, 12 Oct 2025 15:17:04 +0300 Subject: [PATCH] spi: airoha: buffer must be 0xff-ed before writing During writing, the entire flash page (including OOB) will be updated with the values from the temporary buffer, so we need to fill the untouched areas of the buffer with 0xff value to prevent accidental data overwriting. Signed-off-by: Mikhail Kshevetskiy Reviewed-by: AngeloGioacchino Del Regno Link: https://patch.msgid.link/20251012121707.2296160-14-mikhail.kshevetskiy@iopsys.eu Signed-off-by: Mark Brown --- drivers/spi/spi-airoha-snfi.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/spi/spi-airoha-snfi.c b/drivers/spi/spi-airoha-snfi.c index 437ab6745b1a5..8408aee9c06ed 100644 --- a/drivers/spi/spi-airoha-snfi.c +++ b/drivers/spi/spi-airoha-snfi.c @@ -776,7 +776,11 @@ static ssize_t airoha_snand_dirmap_write(struct spi_mem_dirmap_desc *desc, return -EOPNOTSUPP; } + if (offs > 0) + memset(txrx_buf, 0xff, offs); memcpy(txrx_buf + offs, buf, len); + if (bytes > offs + len) + memset(txrx_buf + offs + len, 0xff, bytes - offs - len); err = airoha_snand_set_mode(as_ctrl, SPI_MODE_DMA); if (err < 0) -- 2.47.3