From 18630c36fa8880b5104498c0151c24416f70a7c8 Mon Sep 17 00:00:00 2001 From: Christophe Kerello Date: Tue, 12 Aug 2025 09:30:08 +0200 Subject: [PATCH] mtd: rawnand: stm32_fmc2: fix ECC overwrite commit 811c0da4542df3c065f6cb843ced68780e27bb44 upstream. In case OOB write is requested during a data write, ECC is currently lost. Avoid this issue by only writing in the free spare area. This issue has been seen with a YAFFS2 file system. Signed-off-by: Christophe Kerello Cc: stable@vger.kernel.org Fixes: 2cd457f328c1 ("mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver") Signed-off-by: Miquel Raynal Signed-off-by: Greg Kroah-Hartman --- drivers/mtd/nand/raw/stm32_fmc2_nand.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c index ad4d944ada0c..0d9afc960c83 100644 --- a/drivers/mtd/nand/raw/stm32_fmc2_nand.c +++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c @@ -1037,9 +1037,21 @@ static int stm32_fmc2_sequencer_write(struct nand_chip *chip, /* Write oob */ if (oob_required) { - ret = nand_change_write_column_op(chip, mtd->writesize, - chip->oob_poi, mtd->oobsize, - false); + unsigned int offset_in_page = mtd->writesize; + const void *buf = chip->oob_poi; + unsigned int len = mtd->oobsize; + + if (!raw) { + struct mtd_oob_region oob_free; + + mtd_ooblayout_free(mtd, 0, &oob_free); + offset_in_page += oob_free.offset; + buf += oob_free.offset; + len = oob_free.length; + } + + ret = nand_change_write_column_op(chip, offset_in_page, + buf, len, false); if (ret) return ret; }