Hi Linus,
On 2017/6/14 19:48, Linus Walleij wrote:
mmc_blk_ioctl() calls either mmc_blk_ioctl_cmd() or
mmc_blk_ioctl_multi_cmd() and each of these make the same
check. Factor it into the first call and save one chunk
of duplicate code.
Probably you still cannot save the check like what this patch
does. Refer to commit,
83c742c344c08 ("mmc: block: fix ABI regression of mmc_blk_ioctl")
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
drivers/mmc/core/block.c | 24 ++++++++----------------
1 file changed, 8 insertions(+), 16 deletions(-)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 1ce6012ce3c1..c80bee4a9cff 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -566,14 +566,6 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
int err = 0, ioc_err = 0;
struct request *req;
- /*
- * The caller must have CAP_SYS_RAWIO, and must be calling this on the
- * whole block device, not on a partition. This prevents overspray
- * between sibling partitions.
- */
- if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
- return -EPERM;
-
idata = mmc_blk_ioctl_copy_from_user(ic_ptr);
if (IS_ERR(idata))
return PTR_ERR(idata);
@@ -626,14 +618,6 @@ static int mmc_blk_ioctl_multi_cmd(struct block_device *bdev,
__u64 num_of_cmds;
struct request *req;
- /*
- * The caller must have CAP_SYS_RAWIO, and must be calling this on the
- * whole block device, not on a partition. This prevents overspray
- * between sibling partitions.
- */
- if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
- return -EPERM;
-
if (copy_from_user(&num_of_cmds, &user->num_of_cmds,
sizeof(num_of_cmds)))
return -EFAULT;
@@ -700,6 +684,14 @@ static int mmc_blk_ioctl_multi_cmd(struct block_device *bdev,
static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long arg)
{
+ /*
+ * The caller must have CAP_SYS_RAWIO, and must be calling this on the
+ * whole block device, not on a partition. This prevents overspray
+ * between sibling partitions.
+ */
+ if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
+ return -EPERM;
+
switch (cmd) {
case MMC_IOC_CMD:
return mmc_blk_ioctl_cmd(bdev,
--
Best Regards
Shawn Lin
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
