If tb_drom_read() fails, sw->drom is freed but not set to NULL. sw->drom
is then freed again in the error path of tb_switch_alloc().
The bug can be triggered by unplugging a thunderbolt device shortly after
it is detected by the thunderbolt driver.
Clear sw->drom if tb_drom_read() fails.
[bhelgaas: add Fixes:, stable versions of interest]
Fixes: 343fcb8c70 ("thunderbolt: Fix nontrivial endpoint devices.")
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v3.17+
CC: Lukas Wunner <lukas@wunner.de>
2ffa9a5d76