Commits
Harry Pan committed 16c4cb19fa8
usb: core: safely deal with the dynamic quirk lists
Applying dynamic usbcore quirks in early booting when the slab is
not yet ready would cause kernel panic of null pointer dereference
because the quirk_count has been counted as 1 while the quirk_list
was failed to allocate.
i.e.,
[ 1.044970] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 1.044995] IP: [<ffffffffb0953ec7>] usb_detect_quirks+0x88/0xd1
[ 1.045016] PGD 0
[ 1.045026] Oops: 0000 [#1] PREEMPT SMP
[ 1.046986] gsmi: Log Shutdown Reason 0x03
[ 1.046995] Modules linked in:
[ 1.047008] CPU: 0 PID: 81 Comm: kworker/0:3 Not tainted 4.4.154 #28
[ 1.047016] Hardware name: Google Coral/Coral, BIOS Google_Coral.10068.27.0 12/04/2017
[ 1.047028] Workqueue: usb_hub_wq hub_event
[ 1.047037] task: ffff88017a321c80 task.stack: ffff88017a384000
[ 1.047044] RIP: 0010:[<ffffffffb0953ec7>] [<ffffffffb0953ec7>] usb_detect_quirks+0x88/0xd1
To tackle this odd, let's balance the quirk_count to 0 when the kcalloc
call fails, and defer the quirk setting into a lower level callback
which ensures that the kernel memory management has been initialized.
Fixes: 027bd6cafd9a ("usb: core: Add "quirks" parameter for usbcore")
Signed-off-by: Harry Pan <harry.pan@intel.com>
Acked-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>