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 | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c index 00208ffbe2e7..a54bf964521f 100644 --- a/drivers/platform/chrome/cros_ec_typec.c +++ b/drivers/platform/chrome/cros_ec_typec.c @@ -168,10 +168,13 @@ 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_retimer_put(port->retimer); + port->retimer = NULL; retimer_sw_err: typec_mux_put(port->mux); + port->mux = NULL; mux_err: return -ENODEV; }