Messages in this thread Patch in this message | | | From | Kuninori Morimoto <> | Subject | [PATCH 2/2 v2] mmc: cast unsigned int to typeof(sector_t) to avoid unexpected error | Date | Mon, 11 May 2015 07:35:28 +0000 |
| |
From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
card->csd.capacity is defined as "unsigned int", and sector_t is defined as "u64" or "unsigned long" (depends on CONFIG_LBDAF). Thus, sector_t data might have strange data (see below). This patch cast it to typeof(sector_t) Special thanks to coverity <http://www.coverity.com>
ex) if sector_t was u64
unsigned int data; sector_t sector;
data = 0x800000; sector = (data << 8); // 0xffffffff80000000 sector = (((typeof(sector_t))data) << 8); // 0x80000000
or
data = 0x80000000; sector = (data << 8); // 0x0 sector = (((typeof(sector_t))data) << 8); // 0x8000000000
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> --- v1 -> v2
- tidyup log comment - tidyup line over 80 characters
drivers/mmc/card/block.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index 60f7141..029a872 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -2217,7 +2217,8 @@ static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card) * The CSD capacity field is in units of read_blkbits. * set_capacity takes units of 512 bytes. */ - size = card->csd.capacity << (card->csd.read_blkbits - 9); + size = (typeof(sector_t))card->csd.capacity + << (card->csd.read_blkbits - 9); } return mmc_blk_alloc_req(card, &card->dev, size, false, NULL, -- 1.9.1
| |