Searched hist:"4231 d47e6fe69f061f96c98c30eaf9fb4c14b96d" (Results 1 – 2 of 2) sorted by relevance
/openbmc/linux/drivers/net/usb/ |
H A D | usbnet.c | diff 5b6e9bcdeb65634b4ad604eb4536404bbfc62cfa Wed Apr 25 22:33:46 CDT 2012 Ming Lei <tom.leiming@gmail.com> usbnet: fix skb traversing races during unlink(v2)
Commit 4231d47e6fe69f061f96c98c30eaf9fb4c14b96d(net/usbnet: avoid recursive locking in usbnet_stop()) fixes the recursive locking problem by releasing the skb queue lock before unlink, but may cause skb traversing races: - after URB is unlinked and the queue lock is released, the refered skb and skb->next may be moved to done queue, even be released - in skb_queue_walk_safe, the next skb is still obtained by next pointer of the last skb - so maybe trigger oops or other problems
This patch extends the usage of entry->state to describe 'start_unlink' state, so always holding the queue(rx/tx) lock to change the state if the referd skb is in rx or tx queue because we need to know if the refered urb has been started unlinking in unlink_urbs.
The other part of this patch is based on Huajun's patch: always traverse from head of the tx/rx queue to get skb which is to be unlinked but not been started unlinking.
Signed-off-by: Huajun Li <huajun.li.lee@gmail.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Cc: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: David S. Miller <davem@davemloft.net> diff 0956a8c20b23d429e79ff86d4325583fc06f9eb4 Wed Mar 21 22:22:18 CDT 2012 tom.leiming@gmail.com <tom.leiming@gmail.com> usbnet: increase URB reference count before usb_unlink_urb
Commit 4231d47e6fe69f061f96c98c30eaf9fb4c14b96d(net/usbnet: avoid recursive locking in usbnet_stop()) fixes the recursive locking problem by releasing the skb queue lock, but it makes usb_unlink_urb racing with defer_bh, and the URB to being unlinked may be freed before or during calling usb_unlink_urb, so use-after-free problem may be triggerd inside usb_unlink_urb.
The patch fixes the use-after-free problem by increasing URB reference count with skb queue lock held before calling usb_unlink_urb, so the URB won't be freed until return from usb_unlink_urb.
Cc: stable@kernel.org Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Oliver Neukum <oliver@neukum.org> Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: David S. Miller <davem@davemloft.net> diff 4231d47e6fe69f061f96c98c30eaf9fb4c14b96d Wed Mar 07 04:19:28 CST 2012 Sebastian Siewior <bigeasy@linutronix.de> net/usbnet: avoid recursive locking in usbnet_stop()
|kernel BUG at kernel/rtmutex.c:724! |[<c029599c>] (rt_spin_lock_slowlock+0x108/0x2bc) from [<c01c2330>] (defer_bh+0x1c/0xb4) |[<c01c2330>] (defer_bh+0x1c/0xb4) from [<c01c3afc>] (rx_complete+0x14c/0x194) |[<c01c3afc>] (rx_complete+0x14c/0x194) from [<c01cac88>] (usb_hcd_giveback_urb+0xa0/0xf0) |[<c01cac88>] (usb_hcd_giveback_urb+0xa0/0xf0) from [<c01e1ff4>] (musb_giveback+0x34/0x40) |[<c01e1ff4>] (musb_giveback+0x34/0x40) from [<c01e2b1c>] (musb_advance_schedule+0xb4/0x1c0) |[<c01e2b1c>] (musb_advance_schedule+0xb4/0x1c0) from [<c01e2ca8>] (musb_cleanup_urb.isra.9+0x80/0x8c) |[<c01e2ca8>] (musb_cleanup_urb.isra.9+0x80/0x8c) from [<c01e2ed0>] (musb_urb_dequeue+0xec/0x108) |[<c01e2ed0>] (musb_urb_dequeue+0xec/0x108) from [<c01cbb90>] (unlink1+0xbc/0xcc) |[<c01cbb90>] (unlink1+0xbc/0xcc) from [<c01cc2ec>] (usb_hcd_unlink_urb+0x54/0xa8) |[<c01cc2ec>] (usb_hcd_unlink_urb+0x54/0xa8) from [<c01c2a84>] (unlink_urbs.isra.17+0x2c/0x58) |[<c01c2a84>] (unlink_urbs.isra.17+0x2c/0x58) from [<c01c2b44>] (usbnet_terminate_urbs+0x94/0x10c) |[<c01c2b44>] (usbnet_terminate_urbs+0x94/0x10c) from [<c01c2d68>] (usbnet_stop+0x100/0x15c) |[<c01c2d68>] (usbnet_stop+0x100/0x15c) from [<c020f718>] (__dev_close_many+0x94/0xc8)
defer_bh() takes the lock which is hold during unlink_urbs(). The safe walk suggest that the skb will be removed from the list and this is done by defer_bh() so it seems to be okay to drop the lock here.
Cc: stable@kernel.org Reported-by: AnÃbal Almeida Pinto <anibal.pinto@efacec.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Oliver Neukum <oliver@neukum.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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/openbmc/linux/include/linux/usb/ |
H A D | usbnet.h | diff 5b6e9bcdeb65634b4ad604eb4536404bbfc62cfa Wed Apr 25 22:33:46 CDT 2012 Ming Lei <tom.leiming@gmail.com> usbnet: fix skb traversing races during unlink(v2)
Commit 4231d47e6fe69f061f96c98c30eaf9fb4c14b96d(net/usbnet: avoid recursive locking in usbnet_stop()) fixes the recursive locking problem by releasing the skb queue lock before unlink, but may cause skb traversing races: - after URB is unlinked and the queue lock is released, the refered skb and skb->next may be moved to done queue, even be released - in skb_queue_walk_safe, the next skb is still obtained by next pointer of the last skb - so maybe trigger oops or other problems
This patch extends the usage of entry->state to describe 'start_unlink' state, so always holding the queue(rx/tx) lock to change the state if the referd skb is in rx or tx queue because we need to know if the refered urb has been started unlinking in unlink_urbs.
The other part of this patch is based on Huajun's patch: always traverse from head of the tx/rx queue to get skb which is to be unlinked but not been started unlinking.
Signed-off-by: Huajun Li <huajun.li.lee@gmail.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Cc: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
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