| Message ID | 20200325161249.55095-13-glider@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add KernelMemorySanitizer infrastructure | expand |
On Wed, Mar 25, 2020 at 5:13 PM <glider@google.com> wrote: > > KMSAN assumes shadow and origin pages for every allocated page are > accessible. For pages in vmalloc region those metadata pages reside in > [VMALLOC_END, VMALLOC_META_END), therefore we must sync a bigger memory > region. > > Signed-off-by: Alexander Potapenko <glider@google.com> > To: Alexander Potapenko <glider@google.com> > Cc: Ingo Molnar <mingo@elte.hu> > Cc: Vegard Nossum <vegard.nossum@oracle.com> > Cc: Dmitry Vyukov <dvyukov@google.com> > Cc: Marco Elver <elver@google.com> > Cc: Andrey Konovalov <andreyknvl@google.com> > Cc: linux-mm@kvack.org Reviewed-by: Andrey Konovalov <andreyknvl@google.com> > > --- > > Change-Id: I0d54855489870ef1180b37fe2120b601da464bf7 > --- > arch/x86/mm/fault.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c > index a51df516b87bf..d22e373fa2124 100644 > --- a/arch/x86/mm/fault.c > +++ b/arch/x86/mm/fault.c > @@ -331,11 +331,21 @@ static void dump_pagetable(unsigned long address) > > void vmalloc_sync_mappings(void) > { > +#ifndef CONFIG_KMSAN > /* > * 64-bit mappings might allocate new p4d/pud pages > * that need to be propagated to all tasks' PGDs. > */ > sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END); > +#else > + /* > + * For KMSAN, make sure metadata pages for vmalloc area and modules are > + * also synced. > + */ > + sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_META_END); > + sync_global_pgds(MODULES_SHADOW_START & PGDIR_MASK, > + MODULES_ORIGIN_END); > +#endif > } > > void vmalloc_sync_unmappings(void) > @@ -360,7 +370,17 @@ static noinline int vmalloc_fault(unsigned long address) > pte_t *pte; > > /* Make sure we are in vmalloc area: */ > +#ifdef CONFIG_KMSAN > + /* > + * For KMSAN, make sure metadata pages for vmalloc area and modules are > + * also synced. > + */ > + if (!(address >= VMALLOC_START && address < VMALLOC_META_END) && > + !(address >= MODULES_SHADOW_START && > + address < MODULES_ORIGIN_END)) > +#else > if (!(address >= VMALLOC_START && address < VMALLOC_END)) > +#endif > return -1; > > /* > -- > 2.25.1.696.g5e7596f4ac-goog >
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index a51df516b87bf..d22e373fa2124 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -331,11 +331,21 @@ static void dump_pagetable(unsigned long address) void vmalloc_sync_mappings(void) { +#ifndef CONFIG_KMSAN /* * 64-bit mappings might allocate new p4d/pud pages * that need to be propagated to all tasks' PGDs. */ sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END); +#else + /* + * For KMSAN, make sure metadata pages for vmalloc area and modules are + * also synced. + */ + sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_META_END); + sync_global_pgds(MODULES_SHADOW_START & PGDIR_MASK, + MODULES_ORIGIN_END); +#endif } void vmalloc_sync_unmappings(void) @@ -360,7 +370,17 @@ static noinline int vmalloc_fault(unsigned long address) pte_t *pte; /* Make sure we are in vmalloc area: */ +#ifdef CONFIG_KMSAN + /* + * For KMSAN, make sure metadata pages for vmalloc area and modules are + * also synced. + */ + if (!(address >= VMALLOC_START && address < VMALLOC_META_END) && + !(address >= MODULES_SHADOW_START && + address < MODULES_ORIGIN_END)) +#else if (!(address >= VMALLOC_START && address < VMALLOC_END)) +#endif return -1; /*
KMSAN assumes shadow and origin pages for every allocated page are accessible. For pages in vmalloc region those metadata pages reside in [VMALLOC_END, VMALLOC_META_END), therefore we must sync a bigger memory region. Signed-off-by: Alexander Potapenko <glider@google.com> To: Alexander Potapenko <glider@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Marco Elver <elver@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: linux-mm@kvack.org --- Change-Id: I0d54855489870ef1180b37fe2120b601da464bf7 --- arch/x86/mm/fault.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)