The patch titled
fs-execc-restrict-initial-stack-space-expansion-to-rlimit-cleanup
has been added to the -mm tree. Its filename is
fs-execc-restrict-initial-stack-space-expansion-to-rlimit-cleanup.patch
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------------------------------------------------------
Subject: fs-execc-restrict-initial-stack-space-expansion-to-rlimit-cleanup
From: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Americo Wang <xiyou.wangcong@xxxxxxxxx>
Cc: Anton Blanchard <anton@xxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: James Morris <jmorris@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Serge Hallyn <serue@xxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/exec.c | 37 +++++++++++++++++++++----------------
1 file changed, 21 insertions(+), 16 deletions(-)
diff -puN fs/exec.c~fs-execc-restrict-initial-stack-space-expansion-to-rlimit-cleanup fs/exec.c
--- a/fs/exec.c~fs-execc-restrict-initial-stack-space-expansion-to-rlimit-cleanup
+++ a/fs/exec.c
@@ -555,7 +555,6 @@ static int shift_arg_pages(struct vm_are
}
#define EXTRA_STACK_VM_PAGES 20 /* random */
-#define ALIGN_DOWN(addr,size) ((addr)&(~((size)-1)))
/*
* Finalizes the stack vm_area_struct. The flags and permissions are updated,
@@ -571,7 +570,10 @@ int setup_arg_pages(struct linux_binprm
struct vm_area_struct *vma = bprm->vma;
struct vm_area_struct *prev = NULL;
unsigned long vm_flags;
- unsigned long stack_base, stack_expand, stack_expand_lim, stack_size;
+ unsigned long stack_base;
+ unsigned long stack_size;
+ unsigned long stack_expand;
+ unsigned long rlim_stack;
#ifdef CONFIG_STACK_GROWSUP
/* Limit stack size to 1GB */
@@ -630,22 +632,25 @@ int setup_arg_pages(struct linux_binprm
stack_expand = EXTRA_STACK_VM_PAGES * PAGE_SIZE;
stack_size = vma->vm_end - vma->vm_start;
- if (rlimit(RLIMIT_STACK) < stack_size)
- stack_expand_lim = 0; /* don't shrick the stack */
- else
- /*
- * Align this down to a page boundary as expand_stack
- * will align it up.
- */
- stack_expand_lim = ALIGN_DOWN(rlimit(RLIMIT_STACK) - stack_size,
- PAGE_SIZE);
- /* Initial stack must not cause stack overflow. */
- if (stack_expand > stack_expand_lim)
- stack_expand = stack_expand_lim;
+ /*
+ * Align this down to a page boundary as expand_stack
+ * will align it up.
+ */
+ rlim_stack = rlimit(RLIMIT_STACK) & PAGE_MASK;
+ if (rlim_stack < stack_size)
+ rlim_stack = stack_size;
#ifdef CONFIG_STACK_GROWSUP
- stack_base = vma->vm_end + stack_expand;
+ if (stack_size + stack_expand > rlim_stack) {
+ stack_base = vma->vm_start + rlim_stack;
+ } else {
+ stack_base = vma->vm_end + stack_expand;
+ }
#else
- stack_base = vma->vm_start - stack_expand;
+ if (stack_size + stack_expand > rlim_stack) {
+ stack_base = vma->vm_end - rlim_stack;
+ } else {
+ stack_base = vma->vm_start - stack_expand;
+ }
#endif
ret = expand_stack(vma, stack_base);
if (ret)
_
Patches currently in -mm which might be from kosaki.motohiro@xxxxxxxxxxxxxx are
linux-next.patch
fs-execc-restrict-initial-stack-space-expansion-to-rlimit.patch
fs-execc-restrict-initial-stack-space-expansion-to-rlimit-cleanup.patch
fs-execc-restrict-initial-stack-space-expansion-to-rlimit-cleanup-cleanup.patch
percpu_counter-make-__percpu_counter_add-an-inline-function-on-up.patch
sched-cpuacct-use-bigger-percpu-counter-batch-values-for-stats-counters.patch
mm-introduce-dump_page-and-print-symbolic-flag-names.patch
page-allocator-reduce-fragmentation-in-buddy-allocator-by-adding-buddies-that-are-merging-to-the-tail-of-the-free-lists.patch
mlock_vma_pages_range-never-return-negative-value.patch
mlock_vma_pages_range-only-return-success-or-failure.patch
vmscan-check-high-watermark-after-shrink-zone.patch
vmscan-check-high-watermark-after-shrink-zone-fix.patch
vmscan-get_scan_ratio-cleanup.patch
mm-lockdep-annotate-reclaim-context-to-zone-reclaim-too.patch
mm-page_allocc-remove-duplicate-call-to-trace_mm_page_free_direct.patch
mm-page_allocc-adjust-a-call-site-to-trace_mm_page_free_direct.patch
mm-remove-function-free_hot_page.patch
mm-remove-function-free_hot_page-fix.patch
mm-restore-zone-all_unreclaimable-to-independence-word.patch
mm-restore-zone-all_unreclaimable-to-independence-word-fix.patch
mm-restore-zone-all_unreclaimable-to-independence-word-fix-2.patch
mm-fix-mbind-vma-merge-problem.patch
mm-fix-mbind-vma-merge-problem-fix.patch
mm-mempolicyc-fix-indentation-of-the-comments-of-do_migrate_pages.patch
mm-migratec-kill-anon-local-variable-from-migrate_page_copy.patch
mm-change-anon_vma-linking-to-fix-multi-process-server-scalability-issue.patch
mm-change-anon_vma-linking-to-fix-multi-process-server-scalability-issue-further-cleanups.patch
rmap-remove-obsolete-check-from-__page_check_anon_rmap.patch
rmap-move-exclusively-owned-pages-to-own-anon_vma-in-do_wp_page.patch
mm-remove-vm_lock_rmap-code.patch
mm-pm-force-gfp_noio-during-suspend-hibernation-and-resume.patch
prctl-add-pr_set_proctitle_area-option-for-prctl.patch
mm-pass-mm-flags-as-a-coredump-parameter-for-consistency.patch
memcg-move-charges-of-anonymous-swap-fix-2.patch
sysctl-clean-up-vm-related-variable-declarations.patch
sysctl-clean-up-vm-related-variable-declarations-fix.patch
reiser4.patch
--
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