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Subject[PATCH v2] platform/chrome: cros_ec_typec: zero out stale pointers
Date
`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>
---

Changes in v2:
- Updated commit messages;
- No code changes.

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 2a7ff14dc37e..59de4ce01fab 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -173,10 +173,13 @@ 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;
}
--
2.39.0.rc0.267.gcb52ba06e7-goog
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