Re: [PATCH RESEND 4.9.y] net: check before dereferencing netdev_ops during busy poll

2019-07-01 Thread Josh Elsasser
On Jul 1, 2019, at 6:51 PM, David Miller wrote: > I just tried to apply this with "git am" to the current v4.19 -stable > branch and it failed. This is only needed for the v4.9 stable kernel, ndo_busy_poll (and this NPE) went away in kernel 4.11. Sorry, I probably should have called that out m

Re: [PATCH RESEND 4.9.y] net: check before dereferencing netdev_ops during busy poll

2019-07-01 Thread David Miller
From: Josh Elsasser Date: Mon, 1 Jul 2019 16:41:43 -0700 > No changes since V2[1], resent as per discussiond on -stable[2]. I hope > this is the correct way to send net fixes for older LTS releases, I'm > going off of the latest netdev FAQ: I just tried to apply this with "git am" to the curren

[PATCH RESEND 4.9.y] net: check before dereferencing netdev_ops during busy poll

2019-07-01 Thread Josh Elsasser
init_dummy_netdev() leaves its netdev_ops pointer zeroed. This leads to a NULL pointer dereference when sk_busy_loop fires against an iwlwifi wireless adapter and checks napi->dev->netdev_ops->ndo_busy_poll. Avoid this by ensuring napi->dev->netdev_ops is valid before following the pointer, avoidi