[PATCH] [media] Staging: media/lirc: don't call put_ir_rx on rx twice

From: Colin King
Date: Fri Feb 17 2017 - 11:17:42 EST

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

There is an exit path where rx is kfree'd on put_ir_rx and then
a jump to label out_put_xx will again kfree it with another
call to put_ir_rx. Fix this by adding a new label that avoids
this 2nd call to put_ir_rx for this specific case.

Detected with CoverityScan, CID#145119 ("Use after free")

Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
drivers/staging/media/lirc/lirc_zilog.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/lirc/lirc_zilog.c b/drivers/staging/media/lirc/lirc_zilog.c
index 34aac3e..5dd1e62 100644
--- a/drivers/staging/media/lirc/lirc_zilog.c
+++ b/drivers/staging/media/lirc/lirc_zilog.c
@@ -1597,7 +1597,7 @@ static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
i2c_set_clientdata(client, NULL);
put_ir_rx(rx, true);
ir->l.features &= ~LIRC_CAN_REC_LIRCCODE;
- goto out_put_xx;
+ goto out_put_tx;

/* Proceed only if the Tx client is also ready */
@@ -1637,6 +1637,7 @@ static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
if (rx != NULL)
put_ir_rx(rx, true);
if (tx != NULL)
put_ir_tx(tx, true);