From 0df9433fcae02215c8fd79690c134d535c7bb905 Mon Sep 17 00:00:00 2001 From: Naoki Kiryu Date: Wed, 22 Apr 2020 16:43:45 +0200 Subject: [PATCH] usb: typec: altmode: Fix typec_altmode_get_partner sometimes returning an invalid pointer Before this commit, typec_altmode_get_partner would return a const struct typec_altmode * pointing to address 0x08 when to_altmode(adev)->partner was NULL. Add a check for to_altmode(adev)->partner being NULL to fix this. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=206365 BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1785972 Fixes: 5f54a85db5df ("usb: typec: Make sure an alt mode exist before getting its partner") Cc: stable@vger.kernel.org Signed-off-by: Naoki Kiryu Signed-off-by: Hans de Goede Link: https://lore.kernel.org/r/20200422144345.43262-1-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/bus.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/usb/typec/bus.c b/drivers/usb/typec/bus.c index c823122f9cb7..e8ddb81cb6df 100644 --- a/drivers/usb/typec/bus.c +++ b/drivers/usb/typec/bus.c @@ -198,7 +198,10 @@ EXPORT_SYMBOL_GPL(typec_altmode_vdm); const struct typec_altmode * typec_altmode_get_partner(struct typec_altmode *adev) { - return adev ? &to_altmode(adev)->partner->adev : NULL; + if (!adev || !to_altmode(adev)->partner) + return NULL; + + return &to_altmode(adev)->partner->adev; } EXPORT_SYMBOL_GPL(typec_altmode_get_partner);