From 2394e628738933aa014093d93093030f6232946d Mon Sep 17 00:00:00 2001 From: Andreas Persson Date: Mon, 12 Jul 2021 09:54:52 +0200 Subject: [PATCH] mtd: cfi_cmdset_0002: fix crash when erasing/writing AMD cards Erasing an AMD linear flash card (AM29F016D) crashes after the first sector has been erased. Likewise, writing to it crashes after two bytes have been written. The reason is a missing check for a null pointer - the cmdset_priv field is not set for this type of card. Fixes: 4844ef80305d ("mtd: cfi_cmdset_0002: Add support for polling status register") Signed-off-by: Andreas Persson Signed-off-by: Miquel Raynal Link: https://lore.kernel.org/linux-mtd/DB6P189MB05830B3530B8087476C5CFE4C1159@DB6P189MB0583.EURP189.PROD.OUTLOOK.COM --- drivers/mtd/chips/cfi_cmdset_0002.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c index 3097e93..a761134 100644 --- a/drivers/mtd/chips/cfi_cmdset_0002.c +++ b/drivers/mtd/chips/cfi_cmdset_0002.c @@ -119,7 +119,7 @@ static int cfi_use_status_reg(struct cfi_private *cfi) struct cfi_pri_amdstd *extp = cfi->cmdset_priv; u8 poll_mask = CFI_POLL_STATUS_REG | CFI_POLL_DQ; - return extp->MinorVersion >= '5' && + return extp && extp->MinorVersion >= '5' && (extp->SoftwareFeatures & poll_mask) == CFI_POLL_STATUS_REG; } -- 2.7.4