From 6b95ab4218bfa59bc315105127ffe03aef3b5742 Mon Sep 17 00:00:00 2001 From: Anshuman Khandual Date: Tue, 16 Jul 2019 16:27:30 -0700 Subject: mm/ioremap: check virtual address alignment while creating huge mappings Virtual address alignment is essential in ensuring correct clearing for all intermediate level pgtable entries and freeing associated pgtable pages. An unaligned address can end up randomly freeing pgtable page that potentially still contains valid mappings. Hence also check it's alignment along with existing phys_addr check. Signed-off-by: Anshuman Khandual Reviewed-by: Catalin Marinas Cc: Toshi Kani Cc: Will Deacon Cc: Chintan Pandya Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/ioremap.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'lib') diff --git a/lib/ioremap.c b/lib/ioremap.c index 063213685563..a95161d9c883 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -86,6 +86,9 @@ static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr, if ((end - addr) != PMD_SIZE) return 0; + if (!IS_ALIGNED(addr, PMD_SIZE)) + return 0; + if (!IS_ALIGNED(phys_addr, PMD_SIZE)) return 0; @@ -126,6 +129,9 @@ static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr, if ((end - addr) != PUD_SIZE) return 0; + if (!IS_ALIGNED(addr, PUD_SIZE)) + return 0; + if (!IS_ALIGNED(phys_addr, PUD_SIZE)) return 0; @@ -166,6 +172,9 @@ static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr, if ((end - addr) != P4D_SIZE) return 0; + if (!IS_ALIGNED(addr, P4D_SIZE)) + return 0; + if (!IS_ALIGNED(phys_addr, P4D_SIZE)) return 0; -- cgit v1.2.3-55-g7522