From 3a482c3bb421d8ae8a5f7cc716896e149f0f1797 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Mon, 24 Oct 2011 11:46:20 +0200 Subject: [PATCH] [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: Martin Schwidefsky --- arch/s390/mm/pgtable.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 5d56c2b95b14..529a08838376 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -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); -- 2.39.5