uprobes: Suppress uprobe_munmap() from mmput()

[firefly-linux-kernel-4.4.55.git] / kernel / events / uprobes.c

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 5db150b306d24e8b18a80998dd3602453a065065..9db9cdf8ff346d00cb682068544ae3307d3b5116 100644 (file)
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1010,7 +1010,7 @@ static void build_probe_list(struct inode *inode, struct list_head *head)
 int uprobe_mmap(struct vm_area_struct *vma)
 {
        struct list_head tmp_list;
-       struct uprobe *uprobe;
+       struct uprobe *uprobe, *u;
        struct inode *inode;
        int ret, count;
 
@@ -1028,7 +1028,7 @@ int uprobe_mmap(struct vm_area_struct *vma)
        ret = 0;
        count = 0;
 
-       list_for_each_entry(uprobe, &tmp_list, pending_list) {
+       list_for_each_entry_safe(uprobe, u, &tmp_list, pending_list) {
                if (!ret) {
                        loff_t vaddr = vma_address(vma, uprobe->offset);
 
@@ -1076,12 +1076,15 @@ int uprobe_mmap(struct vm_area_struct *vma)
 void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end)
 {
        struct list_head tmp_list;
-       struct uprobe *uprobe;
+       struct uprobe *uprobe, *u;
        struct inode *inode;
 
        if (!atomic_read(&uprobe_events) || !valid_vma(vma, false))
                return;
 
+       if (!atomic_read(&vma->vm_mm->mm_users)) /* called by mmput() ? */
+               return;
+
        if (!atomic_read(&vma->vm_mm->uprobes_state.count))
                return;
 
@@ -1093,7 +1096,7 @@ void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned lon
        mutex_lock(uprobes_mmap_hash(inode));
        build_probe_list(inode, &tmp_list);
 
-       list_for_each_entry(uprobe, &tmp_list, pending_list) {
+       list_for_each_entry_safe(uprobe, u, &tmp_list, pending_list) {
                loff_t vaddr = vma_address(vma, uprobe->offset);
 
                if (vaddr >= start && vaddr < end) {