sdio: fix read buffer overflow

Avoid buffer underrun when parsing an invalid CISTPL_VERS_1.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: David Vrabel <david.vrabel@csr.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index 963f2937c5e3..6636354b48ce 100644
--- a/drivers/mmc/core/sdio_cis.c
+++ b/drivers/mmc/core/sdio_cis.c
@@ -40,7 +40,7 @@ static int cistpl_vers_1(struct mmc_card *card, struct sdio_func *func,
                         nr_strings++;
         }
 
-        if (buf[i-1] != '\0') {
+        if (nr_strings < 4) {
                 printk(KERN_WARNING "SDIO: ignoring broken CISTPL_VERS_1\n");
                 return 0;
         }