[PATCH AUTOSEL 4.4 07/23] drivers: net: fix memory leak in peak_usb_create_dev

[Sasha Levin]

From: Pavel Skripkin <paskrip...@gmail.com>

[ Upstream commit a0b96b4a62745397aee662670cfc2157bac03f55 ]

syzbot reported memory leak in peak_usb.
The problem was in case of failure after calling
->dev_init()[2] in peak_usb_create_dev()[1]. The data
allocated int dev_init() wasn't freed, so simple
->dev_free() call fix this problem.

backtrace:
    [<0000000079d6542a>] kmalloc include/linux/slab.h:552 [inline]
    [<0000000079d6542a>] kzalloc include/linux/slab.h:682 [inline]
    [<0000000079d6542a>] pcan_usb_fd_init+0x156/0x210 
drivers/net/can/usb/peak_usb/pcan_usb_fd.c:868   [2]
    [<00000000c09f9057>] peak_usb_create_dev 
drivers/net/can/usb/peak_usb/pcan_usb_core.c:851 [inline] [1]
    [<00000000c09f9057>] peak_usb_probe+0x389/0x490 
drivers/net/can/usb/peak_usb/pcan_usb_core.c:949

Reported-by: syzbot+91adee8d9ebb9193d...@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskrip...@gmail.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/net/can/usb/peak_usb/pcan_usb_core.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_core.c 
b/drivers/net/can/usb/peak_usb/pcan_usb_core.c
index 7b148174eb76..620db93ab9a3 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb_core.c
+++ b/drivers/net/can/usb/peak_usb/pcan_usb_core.c
@@ -882,7 +882,7 @@ static int peak_usb_create_dev(const struct 
peak_usb_adapter *peak_usb_adapter,
        if (dev->adapter->dev_set_bus) {
                err = dev->adapter->dev_set_bus(dev, 0);
                if (err)
-                       goto lbl_unregister_candev;
+                       goto adap_dev_free;
        }
 
        /* get device number early */
@@ -894,6 +894,10 @@ static int peak_usb_create_dev(const struct 
peak_usb_adapter *peak_usb_adapter,
 
        return 0;
 
+adap_dev_free:
+       if (dev->adapter->dev_free)
+               dev->adapter->dev_free(dev);
+
 lbl_unregister_candev:
        unregister_candev(netdev);
 
-- 
2.30.2