[PATCH] mtd corruption fix

Read the return value before we release the nand device otherwise the
value can become corrupted by another user of chip->ops, ultimately
resulting in filesystem corruption.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Acked-by: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 62b861304e03..c8cbc00243fe 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1093,9 +1093,10 @@ static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
 
         ret = nand_do_read_ops(mtd, from, &chip->ops);
 
+        *retlen = chip->ops.retlen;
+
         nand_release_device(mtd);
 
-        *retlen = chip->ops.retlen;
         return ret;
 }
 
@@ -1691,9 +1692,10 @@ static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
 
         ret = nand_do_write_ops(mtd, to, &chip->ops);
 
+        *retlen = chip->ops.retlen;
+
         nand_release_device(mtd);
 
-        *retlen = chip->ops.retlen;
         return ret;
 }