Commit 743a3ee3 authored Jul 27, 2021 by Zenghui Yu Committed by Greg Kroah-Hartman Sep 22, 2021

bcma: Fix memory leak for internally-handled cores



[ Upstream commit b63aed3ff195130fef12e0af590f4838cf0201d8 ]

kmemleak reported that dev_name() of internally-handled cores were leaked
on driver unbinding. Let's use device_initialize() to take refcounts for
them and put_device() to properly free the related stuff.

While looking at it, there's another potential issue for those which should
be *registered* into driver core. If device_register() failed, we put
device once and freed bcma_device structures. In bcma_unregister_cores(),
they're treated as unregistered and we hit both UAF and double-free. That
smells not good and has also been fixed now.

Fixes: ab54bc84 ("bcma: fill core details for every device")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210727025232.663-2-yuzenghui@huawei.com


Signed-off-by: Sasha Levin <sashal@kernel.org>

parent dd6bfcc3

drivers/bcma/main.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -236,6 +236,7 @@ EXPORT_SYMBOL(bcma_core_irq);

		void bcma_prepare_core(struct bcma_bus bus, struct bcma_device core)
		{
		device_initialize(&core->dev);
		core->dev.release = bcma_release_core_dev;
		core->dev.bus = &bcma_bus_type;
		dev_set_name(&core->dev, "bcma%d:%d", bus->num, core->core_index);
		@@ -299,11 +300,10 @@ static void bcma_register_core(struct bcma_bus bus, struct bcma_device core)
		{
		int err;

		err = device_register(&core->dev);
		err = device_add(&core->dev);
		if (err) {
		bcma_err(bus, "Could not register dev for core 0x%03X\n",
		core->id.id);
		put_device(&core->dev);
		return;
		}
		core->dev_registered = true;
		@@ -394,7 +394,7 @@ void bcma_unregister_cores(struct bcma_bus *bus)
		/* Now noone uses internally-handled cores, we can free them */
		list_for_each_entry_safe(core, tmp, &bus->cores, list) {
		list_del(&core->list);
		kfree(core);
		put_device(&core->dev);
		}
		}