From: Mika Westerberg mika.westerberg@linux.intel.com
commit 600c0849cf86b75d86352f59745226273290986a upstream.
Paulian reported a crash that happens when a dock is unplugged during hibernation:
[78436.228217] thunderbolt 0-1: device disconnected [78436.228365] BUG: kernel NULL pointer dereference, address: 00000000000001e0 ... [78436.228397] RIP: 0010:icm_free_unplugged_children+0x109/0x1a0 ... [78436.228432] Call Trace: [78436.228439] icm_rescan_work+0x24/0x30 [78436.228444] process_one_work+0x1a3/0x3a0 [78436.228449] worker_thread+0x30/0x370 [78436.228454] ? process_one_work+0x3a0/0x3a0 [78436.228457] kthread+0x13d/0x160 [78436.228461] ? kthread_park+0x90/0x90 [78436.228465] ret_from_fork+0x1f/0x30
This happens because remove_unplugged_switch() calls tb_switch_remove() that releases the memory pointed by sw so the following lines reference to a memory that might be released already.
Fix this by saving pointer to the parent device before calling tb_switch_remove().
Reported-by: Paulian Bogdan Marinca paulian@marinca.net Fixes: 4f7c2e0d8765 ("thunderbolt: Make sure device runtime resume completes before taking domain lock") Cc: stable@vger.kernel.org Signed-off-by: Mika Westerberg mika.westerberg@linux.intel.com Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/thunderbolt/icm.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
--- a/drivers/thunderbolt/icm.c +++ b/drivers/thunderbolt/icm.c @@ -1973,7 +1973,9 @@ static int complete_rpm(struct device *d
static void remove_unplugged_switch(struct tb_switch *sw) { - pm_runtime_get_sync(sw->dev.parent); + struct device *parent = get_device(sw->dev.parent); + + pm_runtime_get_sync(parent);
/* * Signal this and switches below for rpm_complete because @@ -1984,8 +1986,10 @@ static void remove_unplugged_switch(stru bus_for_each_dev(&tb_bus_type, &sw->dev, NULL, complete_rpm); tb_switch_remove(sw);
- pm_runtime_mark_last_busy(sw->dev.parent); - pm_runtime_put_autosuspend(sw->dev.parent); + pm_runtime_mark_last_busy(parent); + pm_runtime_put_autosuspend(parent); + + put_device(parent); }
static void icm_free_unplugged_children(struct tb_switch *sw)