From f53e2cd0b8ab7d9e390414470bdbd830f660133f Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Fri, 13 Sep 2019 14:14:02 -0700 Subject: [PATCH] x86/mm: Use the correct function type for native_set_fixmap() We call native_set_fixmap indirectly through the function pointer struct pv_mmu_ops::set_fixmap, which expects the first parameter to be 'unsigned' instead of 'enum fixed_addresses'. This patch changes the function type for native_set_fixmap to match the pointer, which fixes indirect call mismatches with Control-Flow Integrity (CFI) checking. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: H . Peter Anvin Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Link: https://lkml.kernel.org/r/20190913211402.193018-1-samitolvanen@google.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/fixmap.h | 2 +- arch/x86/mm/pgtable.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h index 0c47aa82e2e22..28183ee3cc42a 100644 --- a/arch/x86/include/asm/fixmap.h +++ b/arch/x86/include/asm/fixmap.h @@ -156,7 +156,7 @@ extern pte_t *kmap_pte; extern pte_t *pkmap_page_table; void __native_set_fixmap(enum fixed_addresses idx, pte_t pte); -void native_set_fixmap(enum fixed_addresses idx, +void native_set_fixmap(unsigned /* enum fixed_addresses */ idx, phys_addr_t phys, pgprot_t flags); #ifndef CONFIG_PARAVIRT_XXL diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 3e4b9035bb9a8..7bd2c3a52297f 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -643,8 +643,8 @@ void __native_set_fixmap(enum fixed_addresses idx, pte_t pte) fixmaps_set++; } -void native_set_fixmap(enum fixed_addresses idx, phys_addr_t phys, - pgprot_t flags) +void native_set_fixmap(unsigned /* enum fixed_addresses */ idx, + phys_addr_t phys, pgprot_t flags) { /* Sanitize 'prot' against any unsupported bits: */ pgprot_val(flags) &= __default_kernel_pte_mask; -- 2.30.2