Merge remote-tracking branch 'remotes/fslc/4.9-2.3.x-imx' into toradex_4.9-2.3.x-imx-next

Conflicts:
	sound/soc/codecs/sgtl5000.c
	sound/soc/fsl/imx-sgtl5000.c

1 files changed, 18 insertions, 0 deletions

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 5138e781737a..4b207b10db03 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1057,6 +1057,24 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
 					count = -EINTR;
 					goto out_mm;
 				}
+				/*
+				 * Avoid to modify vma->vm_flags
+				 * without locked ops while the
+				 * coredump reads the vm_flags.
+				 */
+				if (!mmget_still_valid(mm)) {
+					/*
+					 * Silently return "count"
+					 * like if get_task_mm()
+					 * failed. FIXME: should this
+					 * function have returned
+					 * -ESRCH if get_task_mm()
+					 * failed like if
+					 * get_proc_task() fails?
+					 */
+					up_write(&mm->mmap_sem);
+					goto out_mm;
+				}
 				for (vma = mm->mmap; vma; vma = vma->vm_next) {
 					vma->vm_flags &= ~VM_SOFTDIRTY;
 					vma_set_page_prot(vma);