Commit 70bb0896 authored Sep 05, 2008 by Andrew Morton Committed by Linus Torvalds Sep 05, 2008

drivers/mmc/card/block.c: fix refcount leak in mmc_block_open()



mmc_block_open() increments md->usage although it returns with -EROFS when
default mounting a MMC/SD card with write protect switch on.  This
reference counting bug prevents /dev/mmcblkX from being released on card
removal, and situation worsen with reinsertion until the minor number
range runs out.

Reported-by:  <sasin@solomon-systech.com>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: <stable@kernel.org>		[2.6.25.x, 2.6.26.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 22f30168

drivers/mmc/card/block.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -103,9 +103,11 @@ static int mmc_blk_open(struct inode inode, struct file filp)
		check_disk_change(inode->i_bdev);
		ret = 0;

		if ((filp->f_mode & FMODE_WRITE) && md->read_only)
		if ((filp->f_mode & FMODE_WRITE) && md->read_only) {
		mmc_blk_put(md);
		ret = -EROFS;
		}
		}

		return ret;
		}

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