| Message ID | 20190417052247.17809-9-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 12:31 AM Alexandre Ghiti <alex@ghiti.fr> wrote: > > This commit takes care of stack randomization and stack guard gap when > computing mmap base address and checks if the task asked for randomization. > This fixes the problem uncovered and not fixed for mips here: > https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1429066.html same URL change here please... > > Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> Acked-by: Kees Cook <keescook@chromium.org> -Kees > --- > arch/mips/mm/mmap.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c > index 2f616ebeb7e0..3ff82c6f7e24 100644 > --- a/arch/mips/mm/mmap.c > +++ b/arch/mips/mm/mmap.c > @@ -21,8 +21,9 @@ 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 ((TASK_SIZE)/6*5) > +#define MIN_GAP (128*1024*1024UL) > +#define MAX_GAP ((TASK_SIZE)/6*5) > +#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) > > static int mmap_is_legacy(struct rlimit *rlim_stack) > { > @@ -38,6 +39,15 @@ static int mmap_is_legacy(struct rlimit *rlim_stack) > 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; > -- > 2.20.1 >
On 4/18/19 1:30 AM, Kees Cook wrote: > On Wed, Apr 17, 2019 at 12:31 AM Alexandre Ghiti <alex@ghiti.fr> wrote: >> This commit takes care of stack randomization and stack guard gap when >> computing mmap base address and checks if the task asked for randomization. >> This fixes the problem uncovered and not fixed for mips here: >> https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1429066.html > same URL change here please... > >> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> > Acked-by: Kees Cook <keescook@chromium.org> Thanks ! > > -Kees > >> --- >> arch/mips/mm/mmap.c | 14 ++++++++++++-- >> 1 file changed, 12 insertions(+), 2 deletions(-) >> >> diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c >> index 2f616ebeb7e0..3ff82c6f7e24 100644 >> --- a/arch/mips/mm/mmap.c >> +++ b/arch/mips/mm/mmap.c >> @@ -21,8 +21,9 @@ 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 ((TASK_SIZE)/6*5) >> +#define MIN_GAP (128*1024*1024UL) >> +#define MAX_GAP ((TASK_SIZE)/6*5) >> +#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) >> >> static int mmap_is_legacy(struct rlimit *rlim_stack) >> { >> @@ -38,6 +39,15 @@ static int mmap_is_legacy(struct rlimit *rlim_stack) >> 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; >> -- >> 2.20.1 >>
Hi Alexandre, On Wed, Apr 17, 2019 at 01:22:44AM -0400, Alexandre Ghiti wrote: > This commit takes care of stack randomization and stack guard gap when > computing mmap base address and checks if the task asked for randomization. > This fixes the 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> For patches 8-10: Acked-by: Paul Burton <paul.burton@mips.com> Thanks for improving this, Paul > --- > arch/mips/mm/mmap.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c > index 2f616ebeb7e0..3ff82c6f7e24 100644 > --- a/arch/mips/mm/mmap.c > +++ b/arch/mips/mm/mmap.c > @@ -21,8 +21,9 @@ 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 ((TASK_SIZE)/6*5) > +#define MIN_GAP (128*1024*1024UL) > +#define MAX_GAP ((TASK_SIZE)/6*5) > +#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) > > static int mmap_is_legacy(struct rlimit *rlim_stack) > { > @@ -38,6 +39,15 @@ static int mmap_is_legacy(struct rlimit *rlim_stack) > 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; > -- > 2.20.1 >
On 4/18/19 5:27 PM, Paul Burton wrote: > Hi Alexandre, > > On Wed, Apr 17, 2019 at 01:22:44AM -0400, Alexandre Ghiti wrote: >> This commit takes care of stack randomization and stack guard gap when >> computing mmap base address and checks if the task asked for randomization. >> This fixes the 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> > For patches 8-10: > > Acked-by: Paul Burton <paul.burton@mips.com> > > Thanks for improving this, Thank you for your time, Alex > Paul > >> --- >> arch/mips/mm/mmap.c | 14 ++++++++++++-- >> 1 file changed, 12 insertions(+), 2 deletions(-) >> >> diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c >> index 2f616ebeb7e0..3ff82c6f7e24 100644 >> --- a/arch/mips/mm/mmap.c >> +++ b/arch/mips/mm/mmap.c >> @@ -21,8 +21,9 @@ 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 ((TASK_SIZE)/6*5) >> +#define MIN_GAP (128*1024*1024UL) >> +#define MAX_GAP ((TASK_SIZE)/6*5) >> +#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) >> >> static int mmap_is_legacy(struct rlimit *rlim_stack) >> { >> @@ -38,6 +39,15 @@ static int mmap_is_legacy(struct rlimit *rlim_stack) >> 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; >> -- >> 2.20.1 >> > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv
diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c index 2f616ebeb7e0..3ff82c6f7e24 100644 --- a/arch/mips/mm/mmap.c +++ b/arch/mips/mm/mmap.c @@ -21,8 +21,9 @@ 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 ((TASK_SIZE)/6*5) +#define MIN_GAP (128*1024*1024UL) +#define MAX_GAP ((TASK_SIZE)/6*5) +#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) static int mmap_is_legacy(struct rlimit *rlim_stack) { @@ -38,6 +39,15 @@ static int mmap_is_legacy(struct rlimit *rlim_stack) 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;
This commit takes care of stack randomization and stack guard gap when computing mmap base address and checks if the task asked for randomization. This fixes the 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/mm/mmap.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)