1 files changed, 27 insertions, 9 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 98b450876f93..3b159c5991b7 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -65,6 +65,7 @@
 #include <linux/perf_event.h>
 #include <linux/posix-timers.h>
 #include <linux/user-return-notifier.h>
+#include <linux/oom.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -300,7 +301,7 @@ out:
 #ifdef CONFIG_MMU
 static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 {
-        struct vm_area_struct *mpnt, *tmp, **pprev;
+        struct vm_area_struct *mpnt, *tmp, *prev, **pprev;
         struct rb_node **rb_link, *rb_parent;
         int retval;
         unsigned long charge;
@@ -328,6 +329,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
         if (retval)
                 goto out;
 
+        prev = NULL;
         for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) {
                 struct file *file;
 
@@ -355,11 +357,11 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
                 if (IS_ERR(pol))
                         goto fail_nomem_policy;
                 vma_set_policy(tmp, pol);
+                tmp->vm_mm = mm;
                 if (anon_vma_fork(tmp, mpnt))
                         goto fail_nomem_anon_vma_fork;
                 tmp->vm_flags &= ~VM_LOCKED;
-                tmp->vm_mm = mm;
-                tmp->vm_next = NULL;
+                tmp->vm_next = tmp->vm_prev = NULL;
                 file = tmp->vm_file;
                 if (file) {
                         struct inode *inode = file->f_path.dentry->d_inode;
@@ -392,6 +394,8 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
                  */
                 *pprev = tmp;
                 pprev = &tmp->vm_next;
+                tmp->vm_prev = prev;
+                prev = tmp;
 
                 __vma_link_rb(mm, tmp, rb_link, rb_parent);
                 rb_link = &tmp->vm_rb.rb_right;
@@ -485,6 +489,7 @@ static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
         mm->cached_hole_size = ~0UL;
         mm_init_aio(mm);
         mm_init_owner(mm, p);
+        atomic_set(&mm->oom_disable_count, 0);
 
         if (likely(!mm_alloc_pgd(mm))) {
                 mm->def_flags = 0;
@@ -738,6 +743,8 @@ good_mm:
         /* Initializing for Swap token stuff */
         mm->token_priority = 0;
         mm->last_interval = 0;
+        if (tsk->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
+                atomic_inc(&mm->oom_disable_count);
 
         tsk->mm = mm;
         tsk->active_mm = mm;
@@ -752,13 +759,13 @@ static int copy_fs(unsigned long clone_flags, struct task_struct *tsk)
         struct fs_struct *fs = current->fs;
         if (clone_flags & CLONE_FS) {
                 /* tsk->fs is already what we want */
-                write_lock(&fs->lock);
+                spin_lock(&fs->lock);
                 if (fs->in_exec) {
-                        write_unlock(&fs->lock);
+                        spin_unlock(&fs->lock);
                         return -EAGAIN;
                 }
                 fs->users++;
-                write_unlock(&fs->lock);
+                spin_unlock(&fs->lock);
                 return 0;
         }
         tsk->fs = copy_fs_struct(fs);
@@ -901,6 +908,8 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
         sig->oom_adj = current->signal->oom_adj;
         sig->oom_score_adj = current->signal->oom_score_adj;
 
+        mutex_init(&sig->cred_guard_mutex);
+
         return 0;
 }
 
@@ -1296,8 +1305,13 @@ bad_fork_cleanup_io:
 bad_fork_cleanup_namespaces:
         exit_task_namespaces(p);
 bad_fork_cleanup_mm:
-        if (p->mm)
+        if (p->mm) {
+                task_lock(p);
+                if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
+                        atomic_dec(&p->mm->oom_disable_count);
+                task_unlock(p);
                 mmput(p->mm);
+        }
 bad_fork_cleanup_signal:
         if (!(clone_flags & CLONE_THREAD))
                 free_signal_struct(p->signal);
@@ -1676,13 +1690,13 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags)
 
                 if (new_fs) {
                         fs = current->fs;
-                        write_lock(&fs->lock);
+                        spin_lock(&fs->lock);
                         current->fs = new_fs;
                         if (--fs->users)
                                 new_fs = NULL;
                         else
                                 new_fs = fs;
-                        write_unlock(&fs->lock);
+                        spin_unlock(&fs->lock);
                 }
 
                 if (new_mm) {
@@ -1690,6 +1704,10 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags)
                         active_mm = current->active_mm;
                         current->mm = new_mm;
                         current->active_mm = new_mm;
+                        if (current->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) {
+                                atomic_dec(&mm->oom_disable_count);
+                                atomic_inc(&new_mm->oom_disable_count);
+                        }
                         activate_mm(active_mm, new_mm);
                         new_mm = mm;
                 }