From: Oliver Neukum oneukum@suse.com
stable inclusion from stable-v5.10.130 commit 0085da9df3dced730027923a6b48f58e9016af91 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5YRJO
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit b55a21b764c1e182014630fa5486d717484ac58f upstream.
usbnet_write_cmd_async() mixed up which buffers need to be freed in which error case.
v2: add Fixes tag v3: fix uninitialized buf pointer
Fixes: 877bd862f32b8 ("usbnet: introduce usbnet 3 command helpers") Signed-off-by: Oliver Neukum oneukum@suse.com Link: https://lore.kernel.org/r/20220705125351.17309-1-oneukum@suse.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Acked-by: Xie XiuQi xiexiuqi@huawei.com --- drivers/net/usb/usbnet.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 74a833ad7aa9..58dd77efcaad 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -2102,7 +2102,7 @@ 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; @@ -2120,7 +2120,7 @@ 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; } }
@@ -2144,14 +2144,21 @@ 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;