diff options
| author | Oleksij Rempel <o.rempel@pengutronix.de> | 2024-11-16 14:05:57 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-11-24 16:28:57 -0800 |
| commit | 03819abbeb11117dcbba40bfe322b88c0c88a6b6 (patch) | |
| tree | 3cdd14b0c71e120736ce84a0aeabaa93b3e9bee0 | |
| parent | f26a29a038ee3982099e867bec2260576a19720f (diff) | |
| download | lwn-03819abbeb11117dcbba40bfe322b88c0c88a6b6.tar.gz lwn-03819abbeb11117dcbba40bfe322b88c0c88a6b6.zip | |
net: usb: lan78xx: Fix double free issue with interrupt buffer allocation
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>
| -rw-r--r-- | drivers/net/usb/lan78xx.c | 29 |
1 files changed, 14 insertions, 15 deletions
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c index 8adf77e3557e..094a47b8b97e 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: |