+++ /dev/null
-diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
-index cd535c7..1b53da9 100644
---- a/arch/x86/mm/fault.c
-+++ b/arch/x86/mm/fault.c
-@@ -599,6 +599,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
- unsigned long address;
- int write, si_code;
- int fault;
-+ int should_exit_no_context = 0;
- #ifdef CONFIG_X86_64
- unsigned long flags;
- #endif
-@@ -886,6 +887,9 @@ no_context:
- oops_end(flags, regs, SIGKILL);
- #endif
-
-+ if (should_exit_no_context)
-+ return;
-+
- /*
- * We ran out of memory, or some other thing happened to us that made
- * us unable to handle the page fault gracefully.
-@@ -911,8 +915,11 @@ do_sigbus:
- up_read(&mm->mmap_sem);
-
- /* Kernel mode? Handle exceptions or die */
-- if (!(error_code & PF_USER))
-+ if (!(error_code & PF_USER)) {
-+ should_exit_no_context = 1;
- goto no_context;
-+ }
-+
- #ifdef CONFIG_X86_32
- /* User space => ok to do another page fault */
- if (is_prefetch(regs, address, error_code))
-diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
-index d8be92a..0325100 100644
---- a/fs/proc/task_mmu.c
-+++ b/fs/proc/task_mmu.c
-@@ -205,6 +205,7 @@ static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
- struct file *file = vma->vm_file;
- int flags = vma->vm_flags;
- unsigned long ino = 0;
-+ unsigned long start;
- dev_t dev = 0;
- int len;
-
-@@ -214,8 +215,13 @@ static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
- ino = inode->i_ino;
- }
-
-+ /* We don't show the stack guard page in /proc/maps */
-+ start = vma->vm_start;
-+ if (vma->vm_flags & VM_GROWSDOWN)
-+ start += PAGE_SIZE;
-+
- seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
-- vma->vm_start,
-+ start,
- vma->vm_end,
- flags & VM_READ ? 'r' : '-',
- flags & VM_WRITE ? 'w' : '-',
-diff --git a/mm/memory.c b/mm/memory.c
-index 1c1a375..2638c6f 100644
---- a/mm/memory.c
-+++ b/mm/memory.c
-@@ -2405,6 +2405,26 @@ out_nomap:
- }
-
- /*
-+ * This is like a special single-page "expand_downwards()",
-+ * except we must first make sure that 'address-PAGE_SIZE'
-+ * doesn't hit another vma.
-+ *
-+ * The "find_vma()" will do the right thing even if we wrap
-+ */
-+static inline int check_stack_guard_page(struct vm_area_struct *vma, unsigned long address)
-+{
-+ address &= PAGE_MASK;
-+ if ((vma->vm_flags & VM_GROWSDOWN) && address == vma->vm_start) {
-+ address -= PAGE_SIZE;
-+ if (find_vma(vma->vm_mm, address) != vma)
-+ return -ENOMEM;
-+
-+ expand_stack(vma, address);
-+ }
-+ return 0;
-+}
-+
-+/*
- * We enter with non-exclusive mmap_sem (to exclude vma changes,
- * but allow concurrent faults), and pte mapped but not yet locked.
- * We return with mmap_sem still held, but pte unmapped and unlocked.
-@@ -2417,9 +2437,13 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
- spinlock_t *ptl;
- pte_t entry;
-
-- /* Allocate our own private page. */
-- pte_unmap(page_table);
-+ pte_unmap(page_table);
-+
-+ /* Check if we need to add a guard page to the stack */
-+ if (check_stack_guard_page(vma, address) < 0)
-+ return VM_FAULT_SIGBUS;
-
-+ /* Allocate our own private page. */
- if (!vx_rss_avail(mm, 1))
- goto oom;
- if (unlikely(anon_vma_prepare(vma)))
-diff --git a/mm/mmap.c b/mm/mmap.c
-index 7201372..bef13a1 100644
---- a/mm/mmap.c
-+++ b/mm/mmap.c
-@@ -1573,7 +1573,7 @@ static int acct_stack_growth(struct vm_area_struct * vma, unsigned long size, un
- * Overcommit.. This must be the final test, as it will
- * update security statistics.
- */
-- if (security_vm_enough_memory(grow))
-+ if (security_vm_enough_memory_mm(mm, grow))
- return -ENOMEM;
-
- /* Ok, everything looks good - let it rip */
git://git.onelab.eu / linux-2.6.git / commitdiff