From: Huang, Tao <huangtao@rock-chips.com>
Date: Fri, 4 Mar 2016 09:06:12 +0000 (+0800)
Subject: mmc: block: ioctl return EINVAL if cmd unknown
X-Git-Tag: firefly_0821_release~3288
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7c1abbfe2a27bae41202d4b46687f82eba0c1d5b;p=firefly-linux-kernel-4.4.55.git

mmc: block: ioctl return EINVAL if cmd unknown

We should return -EINVAL if cmd is not MMC_IOC_CMD or MMC_IOC_MULTI_CMD,
otherwise blkdev_roset will return -EPERM.

Android adb, make_block_device_writable ioctl BLKROSET will return error,
make adb remount with error:
remount of /system failed;
couldn't make block device writable: Operation not permitted

Change-Id: I7d0a5727110c0fd9ad301a377e5002eae23f8aed
Fixes: a5f5774c55a2 ("mmc: block: Add new ioctl to send multi commands")
Signed-off-by: Huang, Tao <huangtao@rock-chips.com>
---

diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 7befdaee555a..6efc81ea5dc5 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -690,6 +690,11 @@ cmd_err:
 static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode,
 	unsigned int cmd, unsigned long arg)
 {
+#ifdef CONFIG_ARCH_ROCKCHIP
+	if (cmd != MMC_IOC_CMD && cmd != MMC_IOC_MULTI_CMD)
+		return -EINVAL;
+#endif
+
 	/*
 	 * The caller must have CAP_SYS_RAWIO, and must be calling this on the
 	 * whole block device, not on a partition.  This prevents overspray