diff mbox series

uprobes: use READ_ONCE() to read mm->uprobes_state.xol_area in concurrent environment

Message ID tencent_088804E150842691191FD0021AEE8649EB0A@qq.com
State New
Headers
Series uprobes: use READ_ONCE() to read mm->uprobes_state.xol_area in concurrent environment |

Commit Message

linke li Feb. 24, 2024, 10:25 a.m. UTC 
  In function get_xol_area(), mm->uprobes_state.xol_area is read using 
READ_ONCE() in line 1534

1534   area = READ_ONCE(mm->uprobes_state.xol_area); /* ^^^ */

while read directly in line 1530

1530   	if (!mm->uprobes_state.xol_area)
1531	    __create_xol_area(0);

In the same environment, reads in two places should have the same
protection.

Signed-off-by: linke li <lilinke99@qq.com>
---
 kernel/events/uprobes.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 929e98c62965..e110941fbc6b 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1527,7 +1527,7 @@  static struct xol_area *get_xol_area(void)
 	struct mm_struct *mm = current->mm;
 	struct xol_area *area;
 
-	if (!mm->uprobes_state.xol_area)
+	if (!READ_ONCE(mm->uprobes_state.xol_area))
 		__create_xol_area(0);
 
 	/* Pairs with xol_add_vma() smp_store_release() */