Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Bradley Bolen <bradleybolen@gmail.com>
To:     linux-mmc@vger.kernel.org
Cc:     ulf.hansson@linaro.org, kstewart@linuxfoundation.org,
        tglx@linutronix.de, avri.altman@wdc.com,
        wsa+renesas@sang-engineering.com, yinbo.zhu@nxp.com,
        hongjiefang@asrmicro.com, linux-kernel@vger.kernel.org,
        Bradley Bolen <bradleybolen@gmail.com>
Subject: [PATCH v2] mmc: core: Fix size overflow for mmc partitions
Date:   Wed,  6 Nov 2019 22:25:59 -0500
Message-Id: <1573097159-3914-1-git-send-email-bradleybolen@gmail.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

With large eMMC cards, it is possible to create general purpose
partitions that are bigger than 4GB.  The size member of the mmc_part
struct is only an unsigned int which overflows for gp partitions larger
than 4GB.  Change this to a u64 to handle the overflow.

Signed-off-by: Bradley Bolen <bradleybolen@gmail.com>
---
 drivers/mmc/core/mmc.c   | 6 +++---
 include/linux/mmc/card.h | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index c880489..fc02124 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -297,7 +297,7 @@ static void mmc_manage_enhanced_area(struct mmc_card *card, u8 *ext_csd)
 	}
 }
 
-static void mmc_part_add(struct mmc_card *card, unsigned int size,
+static void mmc_part_add(struct mmc_card *card, u64 size,
 			 unsigned int part_cfg, char *name, int idx, bool ro,
 			 int area_type)
 {
@@ -313,7 +313,7 @@ static void mmc_manage_gp_partitions(struct mmc_card *card, u8 *ext_csd)
 {
 	int idx;
 	u8 hc_erase_grp_sz, hc_wp_grp_sz;
-	unsigned int part_size;
+	u64 part_size;
 
 	/*
 	 * General purpose partition feature support --
@@ -362,7 +362,7 @@ static void mmc_manage_gp_partitions(struct mmc_card *card, u8 *ext_csd)
 static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd)
 {
 	int err = 0, idx;
-	unsigned int part_size;
+	u64 part_size;
 	struct device_node *np;
 	bool broken_hpi = false;
 
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 9b6336a..b59d35b 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -226,7 +226,7 @@ struct mmc_queue_req;
  * MMC Physical partitions
  */
 struct mmc_part {
-	unsigned int	size;	/* partition size (in bytes) */
+	u64		size;	/* partition size (in bytes) */
 	unsigned int	part_cfg;	/* partition type */
 	char	name[MAX_MMC_PART_NAME_LEN];
 	bool	force_ro;	/* to make boot parts RO by default */
-- 
2.7.4