| Message ID | 20220628083128.28472-1-oneukum@suse.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [PATCHv2] usbnet: fix memory leak in error case | expand |
On Tue, 28 Jun 2022 10:31:28 +0200 Oliver Neukum wrote: > - void *buf = NULL; > + void *buf; > > netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x" > " value=0x%04x index=0x%04x size=%d\n", > @@ -2155,7 +2155,7 @@ int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype, > if (!buf) { > netdev_err(dev->net, "Error allocating buffer" > " in %s!\n", __func__); > - goto fail_free; > + goto fail_free_urb; > } > } > > @@ -2179,14 +2179,21 @@ int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype, > if (err < 0) { > netdev_err(dev->net, "Error submitting the control" > " message: status=%d\n", err); > - goto fail_free; > + goto fail_free_all; > } > return 0; > > +fail_free_all: > + kfree(req); > fail_free_buf: > kfree(buf); Seems like the buf can be uninitialized now if data was NULL
On 30.06.22 05:36, Jakub Kicinski wrote: > > Seems like the buf can be uninitialized now if data was NULL Thank you, are right, sending out v3 Regards Oliver
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 1cb6dab3e2d0..c66d2a097b0c 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -2137,10 +2137,10 @@ static void usbnet_async_cmd_cb(struct urb *urb) int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype, u16 value, u16 index, const void *data, u16 size) { - struct usb_ctrlrequest *req = NULL; + struct usb_ctrlrequest *req; struct urb *urb; int err = -ENOMEM; - void *buf = NULL; + void *buf; netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x" " value=0x%04x index=0x%04x size=%d\n", @@ -2155,7 +2155,7 @@ int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype, if (!buf) { netdev_err(dev->net, "Error allocating buffer" " in %s!\n", __func__); - goto fail_free; + goto fail_free_urb; } } @@ -2179,14 +2179,21 @@ int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype, if (err < 0) { netdev_err(dev->net, "Error submitting the control" " message: status=%d\n", err); - goto fail_free; + goto fail_free_all; } return 0; +fail_free_all: + kfree(req); fail_free_buf: kfree(buf); -fail_free: - kfree(req); + /* + * avoid a double free + * needed because the flag can be set only + * after filling the URB + */ + urb->transfer_flags = 0; +fail_free_urb: usb_free_urb(urb); fail: return err;
usbnet_write_cmd_async() mixed up which buffers need to be freed in which error case. v2: add Fixes tag Fixes: 877bd862f32b8 ("usbnet: introduce usbnet 3 command helpers") Signed-off-by: Oliver Neukum <oneukum@suse.com> --- drivers/net/usb/usbnet.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-)