From: Victor Ding victording@chromium.org
[ Upstream commit 9a8aadcf0b459c1257b9477fd6402e1d5952ae07 ]
`cros_typec_get_switch_handles` allocates four pointers when obtaining type-c switch handles. These pointers are all freed if failing to obtain any of them; therefore, pointers in `port` become stale. The stale pointers eventually cause use-after-free or double free in later code paths. Zeroing out all pointer fields after freeing to eliminate these stale pointers.
Fixes: f28adb41dab4 ("platform/chrome: cros_ec_typec: Register Type C switches") Fixes: 1a8912caba02 ("platform/chrome: cros_ec_typec: Get retimer handle") Signed-off-by: Victor Ding victording@chromium.org Acked-by: Prashant Malani pmalani@chromium.org Signed-off-by: Tzung-Bi Shih tzungbi@kernel.org Link: https://lore.kernel.org/r/20221207093924.v2.1.I1864b6a7ee98824118b93677868d2... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/platform/chrome/cros_ec_typec.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c index d63be2b3d10e..b94abb8f7706 100644 --- a/drivers/platform/chrome/cros_ec_typec.c +++ b/drivers/platform/chrome/cros_ec_typec.c @@ -157,8 +157,10 @@ static int cros_typec_get_switch_handles(struct cros_typec_port *port,
role_sw_err: typec_switch_put(port->ori_sw); + port->ori_sw = NULL; ori_sw_err: typec_mux_put(port->mux); + port->mux = NULL; mux_err: return -ENODEV; }