This is a note to let you know that I've just added the patch titled
net: usb: lan78xx: Fix double free issue with interrupt buffer allocation
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-usb-lan78xx-fix-double-free-issue-with-interrupt.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9491c4c822a7e11205e05a7501d08b5fe9f5a2f0
Author: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
Date: Sat Nov 16 14:05:57 2024 +0100
net: usb: lan78xx: Fix double free issue with interrupt buffer allocation
[ 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@xxxxxxxxxxxxx>
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
Link: https://patch.msgid.link/20241116130558.1352230-1-o.rempel@xxxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 366e83ed0a973..b18afd2c7aeed 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -4417,29 +4417,30 @@ 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. */
@@ -4447,7 +4448,7 @@ 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) {
@@ -4469,10 +4470,8 @@ 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:
