From 567190aa704b0d548f029c29017a70ff1cdfd036 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 commit 2394e628738933aa014093d93093030f6232946d upstream. 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: db5b4f3e75fa ("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 Signed-off-by: Greg Kroah-Hartman --- 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 c8b9ab40a1027..9c98ddef0097d 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; } -- 2.39.5