Commit bec18bb0 authored Apr 14, 2022 by Xiaomeng Tong Committed by Greg Kroah-Hartman Jun 14, 2022

firmware: stratix10-svc: fix a missing check on list iterator



[ Upstream commit 5a0793ac66ac0e254d292f129a4d6c526f9f2aff ]

The bug is here:
	pmem->vaddr = NULL;

The list iterator 'pmem' will point to a bogus position containing
HEAD if the list is empty or no element is found. This case must
be checked before any use of the iterator, otherwise it will
lead to a invalid memory access.

To fix this bug, just gen_pool_free/set NULL/list_del() and return
when found, otherwise list_del HEAD and return;

Fixes: 7ca5ce89 ("firmware: add Intel Stratix10 service layer driver")
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>
Link: https://lore.kernel.org/r/20220414035609.2239-1-xiam0nd.tong@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 8ad7b3d9

drivers/firmware/stratix10-svc.c

+6 −6

Original line number	Diff line number	Diff line
		@@ -934,17 +934,17 @@ EXPORT_SYMBOL_GPL(stratix10_svc_allocate_memory);
		void stratix10_svc_free_memory(struct stratix10_svc_chan chan, void kaddr)
		{
		struct stratix10_svc_data_mem *pmem;
		size_t size = 0;

		list_for_each_entry(pmem, &svc_data_mem, node)
		if (pmem->vaddr == kaddr) {
		size = pmem->size;
		break;
		}

		gen_pool_free(chan->ctrl->genpool, (unsigned long)kaddr, size);
		gen_pool_free(chan->ctrl->genpool,
		(unsigned long)kaddr, pmem->size);
		pmem->vaddr = NULL;
		list_del(&pmem->node);
		return;
		}

		list_del(&svc_data_mem);
		}
		EXPORT_SYMBOL_GPL(stratix10_svc_free_memory);