6.6-stable review patch. If anyone has any objections, please let me know.
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From: Oleksij Rempel o.rempel@pengutronix.de
[ Upstream commit 03819abbeb11117dcbba40bfe322b88c0c88a6b6 ]
In lan78xx_probe(), the buffer `buf` was being freed twice: once implicitly through `usb_free_urb(dev->urb_intr)` with the `URB_FREE_BUFFER` flag and again explicitly by `kfree(buf)`. This caused a double free issue.
To resolve this, reordered `kmalloc()` and `usb_alloc_urb()` calls to simplify the initialization sequence and removed the redundant `kfree(buf)`. Now, `buf` is allocated after `usb_alloc_urb()`, ensuring it is correctly managed by `usb_fill_int_urb()` and freed by `usb_free_urb()` as intended.
Fixes: a6df95cae40b ("lan78xx: Fix memory allocation bug") Cc: John Efstathiades john.efstathiades@pebblebay.com Signed-off-by: Oleksij Rempel o.rempel@pengutronix.de Link: https://patch.msgid.link/20241116130558.1352230-1-o.rempel@pengutronix.de Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/usb/lan78xx.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-)
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c index 921ae046f8604..2ae33ecb67494 100644 --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -4414,29 +4414,30 @@ static int lan78xx_probe(struct usb_interface *intf,
period = ep_intr->desc.bInterval; maxp = usb_maxpacket(dev->udev, dev->pipe_intr); - buf = kmalloc(maxp, GFP_KERNEL); - if (!buf) { + + dev->urb_intr = usb_alloc_urb(0, GFP_KERNEL); + if (!dev->urb_intr) { ret = -ENOMEM; goto out5; }
- dev->urb_intr = usb_alloc_urb(0, GFP_KERNEL); - if (!dev->urb_intr) { + buf = kmalloc(maxp, GFP_KERNEL); + if (!buf) { ret = -ENOMEM; - goto out6; - } else { - usb_fill_int_urb(dev->urb_intr, dev->udev, - dev->pipe_intr, buf, maxp, - intr_complete, dev, period); - dev->urb_intr->transfer_flags |= URB_FREE_BUFFER; + goto free_urbs; }
+ usb_fill_int_urb(dev->urb_intr, dev->udev, + dev->pipe_intr, buf, maxp, + intr_complete, dev, period); + dev->urb_intr->transfer_flags |= URB_FREE_BUFFER; + dev->maxpacket = usb_maxpacket(dev->udev, dev->pipe_out);
/* Reject broken descriptors. */ if (dev->maxpacket == 0) { ret = -ENODEV; - goto out6; + goto free_urbs; }
/* driver requires remote-wakeup capability during autosuspend. */ @@ -4444,7 +4445,7 @@ static int lan78xx_probe(struct usb_interface *intf,
ret = lan78xx_phy_init(dev); if (ret < 0) - goto out7; + goto free_urbs;
ret = register_netdev(netdev); if (ret != 0) { @@ -4466,10 +4467,8 @@ static int lan78xx_probe(struct usb_interface *intf,
out8: phy_disconnect(netdev->phydev); -out7: +free_urbs: usb_free_urb(dev->urb_intr); -out6: - kfree(buf); out5: lan78xx_unbind(dev, intf); out4: