| Message ID | 20190417052247.17809-11-alex@ghiti.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Provide generic top-down mmap layout functions | expand |
On Wed, Apr 17, 2019 at 12:33 AM Alexandre Ghiti <alex@ghiti.fr> wrote: > > mips uses a top-down layout by default that fits the generic functions. > At the same time, this commit allows to fix problem uncovered > and not fixed for mips here: > https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1429066.html > > Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> Acked-by: Kees Cook <keescook@chromium.org> -Kees > --- > arch/mips/Kconfig | 1 + > arch/mips/include/asm/processor.h | 5 --- > arch/mips/mm/mmap.c | 67 ------------------------------- > 3 files changed, 1 insertion(+), 72 deletions(-) > > diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig > index 4a5f5b0ee9a9..ec2f07561e4d 100644 > --- a/arch/mips/Kconfig > +++ b/arch/mips/Kconfig > @@ -14,6 +14,7 @@ config MIPS > select ARCH_USE_CMPXCHG_LOCKREF if 64BIT > select ARCH_USE_QUEUED_RWLOCKS > select ARCH_USE_QUEUED_SPINLOCKS > + select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU > select ARCH_WANT_IPC_PARSE_VERSION > select BUILDTIME_EXTABLE_SORT > select CLONE_BACKWARDS > diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h > index aca909bd7841..fba18d4a9190 100644 > --- a/arch/mips/include/asm/processor.h > +++ b/arch/mips/include/asm/processor.h > @@ -29,11 +29,6 @@ > > extern unsigned int vced_count, vcei_count; > > -/* > - * MIPS does have an arch_pick_mmap_layout() > - */ > -#define HAVE_ARCH_PICK_MMAP_LAYOUT 1 > - > #ifdef CONFIG_32BIT > #ifdef CONFIG_KVM_GUEST > /* User space process size is limited to 1GB in KVM Guest Mode */ > diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c > index ffbe69f3a7d9..61e65a69bb09 100644 > --- a/arch/mips/mm/mmap.c > +++ b/arch/mips/mm/mmap.c > @@ -20,43 +20,6 @@ > unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */ > EXPORT_SYMBOL(shm_align_mask); > > -/* gap between mmap and stack */ > -#define MIN_GAP (128*1024*1024UL) > -#define MAX_GAP ((STACK_TOP)/6*5) > -#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) > - > -static int mmap_is_legacy(struct rlimit *rlim_stack) > -{ > - if (current->personality & ADDR_COMPAT_LAYOUT) > - return 1; > - > - if (rlim_stack->rlim_cur == RLIM_INFINITY) > - return 1; > - > - return sysctl_legacy_va_layout; > -} > - > -static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack) > -{ > - unsigned long gap = rlim_stack->rlim_cur; > - unsigned long pad = stack_guard_gap; > - > - /* Account for stack randomization if necessary */ > - if (current->flags & PF_RANDOMIZE) > - pad += (STACK_RND_MASK << PAGE_SHIFT); > - > - /* Values close to RLIM_INFINITY can overflow. */ > - if (gap + pad > gap) > - gap += pad; > - > - if (gap < MIN_GAP) > - gap = MIN_GAP; > - else if (gap > MAX_GAP) > - gap = MAX_GAP; > - > - return PAGE_ALIGN(STACK_TOP - gap - rnd); > -} > - > #define COLOUR_ALIGN(addr, pgoff) \ > ((((addr) + shm_align_mask) & ~shm_align_mask) + \ > (((pgoff) << PAGE_SHIFT) & shm_align_mask)) > @@ -154,36 +117,6 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp, > addr0, len, pgoff, flags, DOWN); > } > > -unsigned long arch_mmap_rnd(void) > -{ > - unsigned long rnd; > - > -#ifdef CONFIG_COMPAT > - if (TASK_IS_32BIT_ADDR) > - rnd = get_random_long() & ((1UL << mmap_rnd_compat_bits) - 1); > - else > -#endif /* CONFIG_COMPAT */ > - rnd = get_random_long() & ((1UL << mmap_rnd_bits) - 1); > - > - return rnd << PAGE_SHIFT; > -} > - > -void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) > -{ > - unsigned long random_factor = 0UL; > - > - if (current->flags & PF_RANDOMIZE) > - random_factor = arch_mmap_rnd(); > - > - if (mmap_is_legacy(rlim_stack)) { > - mm->mmap_base = TASK_UNMAPPED_BASE + random_factor; > - mm->get_unmapped_area = arch_get_unmapped_area; > - } else { > - mm->mmap_base = mmap_base(random_factor, rlim_stack); > - mm->get_unmapped_area = arch_get_unmapped_area_topdown; > - } > -} > - > static inline unsigned long brk_rnd(void) > { > unsigned long rnd = get_random_long(); > -- > 2.20.1 >
On 4/18/19 1:31 AM, Kees Cook wrote: > On Wed, Apr 17, 2019 at 12:33 AM Alexandre Ghiti <alex@ghiti.fr> wrote: >> mips uses a top-down layout by default that fits the generic functions. >> At the same time, this commit allows to fix problem uncovered >> and not fixed for mips here: >> https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1429066.html >> >> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> > Acked-by: Kees Cook <keescook@chromium.org> Thanks ! > > -Kees > >> --- >> arch/mips/Kconfig | 1 + >> arch/mips/include/asm/processor.h | 5 --- >> arch/mips/mm/mmap.c | 67 ------------------------------- >> 3 files changed, 1 insertion(+), 72 deletions(-) >> >> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig >> index 4a5f5b0ee9a9..ec2f07561e4d 100644 >> --- a/arch/mips/Kconfig >> +++ b/arch/mips/Kconfig >> @@ -14,6 +14,7 @@ config MIPS >> select ARCH_USE_CMPXCHG_LOCKREF if 64BIT >> select ARCH_USE_QUEUED_RWLOCKS >> select ARCH_USE_QUEUED_SPINLOCKS >> + select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU >> select ARCH_WANT_IPC_PARSE_VERSION >> select BUILDTIME_EXTABLE_SORT >> select CLONE_BACKWARDS >> diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h >> index aca909bd7841..fba18d4a9190 100644 >> --- a/arch/mips/include/asm/processor.h >> +++ b/arch/mips/include/asm/processor.h >> @@ -29,11 +29,6 @@ >> >> extern unsigned int vced_count, vcei_count; >> >> -/* >> - * MIPS does have an arch_pick_mmap_layout() >> - */ >> -#define HAVE_ARCH_PICK_MMAP_LAYOUT 1 >> - >> #ifdef CONFIG_32BIT >> #ifdef CONFIG_KVM_GUEST >> /* User space process size is limited to 1GB in KVM Guest Mode */ >> diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c >> index ffbe69f3a7d9..61e65a69bb09 100644 >> --- a/arch/mips/mm/mmap.c >> +++ b/arch/mips/mm/mmap.c >> @@ -20,43 +20,6 @@ >> unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */ >> EXPORT_SYMBOL(shm_align_mask); >> >> -/* gap between mmap and stack */ >> -#define MIN_GAP (128*1024*1024UL) >> -#define MAX_GAP ((STACK_TOP)/6*5) >> -#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) >> - >> -static int mmap_is_legacy(struct rlimit *rlim_stack) >> -{ >> - if (current->personality & ADDR_COMPAT_LAYOUT) >> - return 1; >> - >> - if (rlim_stack->rlim_cur == RLIM_INFINITY) >> - return 1; >> - >> - return sysctl_legacy_va_layout; >> -} >> - >> -static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack) >> -{ >> - unsigned long gap = rlim_stack->rlim_cur; >> - unsigned long pad = stack_guard_gap; >> - >> - /* Account for stack randomization if necessary */ >> - if (current->flags & PF_RANDOMIZE) >> - pad += (STACK_RND_MASK << PAGE_SHIFT); >> - >> - /* Values close to RLIM_INFINITY can overflow. */ >> - if (gap + pad > gap) >> - gap += pad; >> - >> - if (gap < MIN_GAP) >> - gap = MIN_GAP; >> - else if (gap > MAX_GAP) >> - gap = MAX_GAP; >> - >> - return PAGE_ALIGN(STACK_TOP - gap - rnd); >> -} >> - >> #define COLOUR_ALIGN(addr, pgoff) \ >> ((((addr) + shm_align_mask) & ~shm_align_mask) + \ >> (((pgoff) << PAGE_SHIFT) & shm_align_mask)) >> @@ -154,36 +117,6 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp, >> addr0, len, pgoff, flags, DOWN); >> } >> >> -unsigned long arch_mmap_rnd(void) >> -{ >> - unsigned long rnd; >> - >> -#ifdef CONFIG_COMPAT >> - if (TASK_IS_32BIT_ADDR) >> - rnd = get_random_long() & ((1UL << mmap_rnd_compat_bits) - 1); >> - else >> -#endif /* CONFIG_COMPAT */ >> - rnd = get_random_long() & ((1UL << mmap_rnd_bits) - 1); >> - >> - return rnd << PAGE_SHIFT; >> -} >> - >> -void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) >> -{ >> - unsigned long random_factor = 0UL; >> - >> - if (current->flags & PF_RANDOMIZE) >> - random_factor = arch_mmap_rnd(); >> - >> - if (mmap_is_legacy(rlim_stack)) { >> - mm->mmap_base = TASK_UNMAPPED_BASE + random_factor; >> - mm->get_unmapped_area = arch_get_unmapped_area; >> - } else { >> - mm->mmap_base = mmap_base(random_factor, rlim_stack); >> - mm->get_unmapped_area = arch_get_unmapped_area_topdown; >> - } >> -} >> - >> static inline unsigned long brk_rnd(void) >> { >> unsigned long rnd = get_random_long(); >> -- >> 2.20.1 >> >
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 4a5f5b0ee9a9..ec2f07561e4d 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -14,6 +14,7 @@ config MIPS select ARCH_USE_CMPXCHG_LOCKREF if 64BIT select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS + select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select ARCH_WANT_IPC_PARSE_VERSION select BUILDTIME_EXTABLE_SORT select CLONE_BACKWARDS diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h index aca909bd7841..fba18d4a9190 100644 --- a/arch/mips/include/asm/processor.h +++ b/arch/mips/include/asm/processor.h @@ -29,11 +29,6 @@ extern unsigned int vced_count, vcei_count; -/* - * MIPS does have an arch_pick_mmap_layout() - */ -#define HAVE_ARCH_PICK_MMAP_LAYOUT 1 - #ifdef CONFIG_32BIT #ifdef CONFIG_KVM_GUEST /* User space process size is limited to 1GB in KVM Guest Mode */ diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c index ffbe69f3a7d9..61e65a69bb09 100644 --- a/arch/mips/mm/mmap.c +++ b/arch/mips/mm/mmap.c @@ -20,43 +20,6 @@ unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */ EXPORT_SYMBOL(shm_align_mask); -/* gap between mmap and stack */ -#define MIN_GAP (128*1024*1024UL) -#define MAX_GAP ((STACK_TOP)/6*5) -#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) - -static int mmap_is_legacy(struct rlimit *rlim_stack) -{ - if (current->personality & ADDR_COMPAT_LAYOUT) - return 1; - - if (rlim_stack->rlim_cur == RLIM_INFINITY) - return 1; - - return sysctl_legacy_va_layout; -} - -static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack) -{ - unsigned long gap = rlim_stack->rlim_cur; - unsigned long pad = stack_guard_gap; - - /* Account for stack randomization if necessary */ - if (current->flags & PF_RANDOMIZE) - pad += (STACK_RND_MASK << PAGE_SHIFT); - - /* Values close to RLIM_INFINITY can overflow. */ - if (gap + pad > gap) - gap += pad; - - if (gap < MIN_GAP) - gap = MIN_GAP; - else if (gap > MAX_GAP) - gap = MAX_GAP; - - return PAGE_ALIGN(STACK_TOP - gap - rnd); -} - #define COLOUR_ALIGN(addr, pgoff) \ ((((addr) + shm_align_mask) & ~shm_align_mask) + \ (((pgoff) << PAGE_SHIFT) & shm_align_mask)) @@ -154,36 +117,6 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp, addr0, len, pgoff, flags, DOWN); } -unsigned long arch_mmap_rnd(void) -{ - unsigned long rnd; - -#ifdef CONFIG_COMPAT - if (TASK_IS_32BIT_ADDR) - rnd = get_random_long() & ((1UL << mmap_rnd_compat_bits) - 1); - else -#endif /* CONFIG_COMPAT */ - rnd = get_random_long() & ((1UL << mmap_rnd_bits) - 1); - - return rnd << PAGE_SHIFT; -} - -void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) -{ - unsigned long random_factor = 0UL; - - if (current->flags & PF_RANDOMIZE) - random_factor = arch_mmap_rnd(); - - if (mmap_is_legacy(rlim_stack)) { - mm->mmap_base = TASK_UNMAPPED_BASE + random_factor; - mm->get_unmapped_area = arch_get_unmapped_area; - } else { - mm->mmap_base = mmap_base(random_factor, rlim_stack); - mm->get_unmapped_area = arch_get_unmapped_area_topdown; - } -} - static inline unsigned long brk_rnd(void) { unsigned long rnd = get_random_long();
mips uses a top-down layout by default that fits the generic functions. At the same time, this commit allows to fix problem uncovered and not fixed for mips here: https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1429066.html Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> --- arch/mips/Kconfig | 1 + arch/mips/include/asm/processor.h | 5 --- arch/mips/mm/mmap.c | 67 ------------------------------- 3 files changed, 1 insertion(+), 72 deletions(-)