From: Sami Tolvanen samitolvanen@google.com
[ Upstream commit f53e2cd0b8ab7d9e390414470bdbd830f660133f ]
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 samitolvanen@google.com Reviewed-by: Kees Cook keescook@chromium.org Cc: Andy Lutomirski luto@kernel.org Cc: Borislav Petkov bp@alien8.de Cc: Dave Hansen dave.hansen@linux.intel.com Cc: H . Peter Anvin hpa@zytor.com Cc: H. Peter Anvin hpa@zytor.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Peter Zijlstra peterz@infradead.org Cc: Rik van Riel riel@surriel.com Cc: Thomas Gleixner tglx@linutronix.de Link: https://lkml.kernel.org/r/20190913211402.193018-1-samitolvanen@google.com Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 0c47aa82e2e2..28183ee3cc42 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 3e4b9035bb9a..7bd2c3a52297 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;