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Commit e73b7fff authored by Martin Schwidefsky's avatar Martin Schwidefsky
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[S390] memory leak with RCU_TABLE_FREE 



The rcu page table free code uses a couple of bits in the page table
pointer passed to tlb_remove_table to discern the different page table
types. __tlb_remove_table extracts the type with an incorrect mask which
leads to memory leaks. The correct mask is ((FRAG_MASK << 4) | FRAG_MASK).

Cc: stable@kernel.org
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent a45aff52

arch/s390/mm/pgtable.c

+3 −2
Original line number Diff line number Diff line
@@ -662,8 +662,9 @@ void page_table_free_rcu(struct mmu_gather *tlb, unsigned long *table) 


void __tlb_remove_table(void *_table)

{

	void *table = (void *)((unsigned long) _table & PAGE_MASK);

	unsigned type = (unsigned long) _table & ~PAGE_MASK;

	const unsigned long mask = (FRAG_MASK << 4) | FRAG_MASK;

	void *table = (void *)((unsigned long) _table & ~mask);

	unsigned type = (unsigned long) _table & mask;



	if (type)

		__page_table_free_rcu(table, type);