[PATCH 3.16.y-ckt 001/126] irda: precedence bug in irlmp_seq_hb_idx()

[Luis Henriques]

3.16.7-ckt21 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter at oracle.com>

commit 50010c20597d14667eff0fdb628309986f195230 upstream.

This is decrementing the pointer, instead of the value stored in the
pointer.  KASan detects it as an out of bounds reference.

Reported-by: "Berry Cheng 程君(成淼)" <chengmiao.cj at alibaba-inc.com>
Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/irda/irlmp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/irda/irlmp.c b/net/irda/irlmp.c
index 98ad6ec4bd3c..8ad149478e19 100644
--- a/net/irda/irlmp.c
+++ b/net/irda/irlmp.c
@@ -1876,7 +1876,7 @@ static void *irlmp_seq_hb_idx(struct irlmp_iter_state *iter, loff_t *off)
 	for (element = hashbin_get_first(iter->hashbin);
 	     element != NULL;
 	     element = hashbin_get_next(iter->hashbin)) {
-		if (!off || *off-- == 0) {
+		if (!off || (*off)-- == 0) {
 			/* NB: hashbin left locked */
 			return element;
 		}