[PATCH AUTOSEL 5.4 15/39] drivers: net: fix memory leak in peak_usb_create_dev

From: Sasha Levin
Date: Mon Apr 12 2021 - 12:36:24 EST


From: Pavel Skripkin <paskripkin@xxxxxxxxx>

[ 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+91adee8d9ebb9193d22d@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 f22089101cdd..4b18f37beb4c 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb_core.c
+++ b/drivers/net/can/usb/peak_usb/pcan_usb_core.c
@@ -856,7 +856,7 @@ 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 */
@@ -868,6 +868,10 @@ 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