[PATCH v5.10-v6.1] driver core: bus: Fix double free in driver API bus_register() - Linux-stable-mirror

2 Dec 2024

From: Zijun Hu quic_zijuhu@quicinc.com
[ Upstream commit bfa54a793ba77ef696755b66f3ac4ed00c7d1248 ]
For bus_register(), any error which happens after kset_register() will
cause that @priv are freed twice, fixed by setting @priv with NULL after
the first free.
Signed-off-by: Zijun Hu quic_zijuhu@quicinc.com
Link: https://lore.kernel.org/r/20240727-bus_register_fix-v1-1-fed8dd0dba7a@quicin...
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
Signed-off-by: Sasha Levin sashal@kernel.org
[ Brennan : Backport requires bus->p = NULL instead of priv = NULL ]
Signed-off-by: Brennan Lamoreaux brennan.lamoreaux@broadcom.com
---
 drivers/base/bus.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 339a9edcde5f..941532ddfdc6 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -853,6 +853,8 @@ int bus_register(struct bus_type *bus)
    bus_remove_file(bus, &bus_attr_uevent);
 bus_uevent_fail:
    kset_unregister(&bus->p->subsys);
+	/* Above kset_unregister() will kfree @bus->p */
+	bus->p = NULL;
 out:
    kfree(bus->p);
    bus->p = NULL;
--
2.39.4

    