lkml.org 
[lkml]   [2017]   [Oct]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] fs/cachefiles: Fix a possible sleep-in-atomic bug in cachefiles_printk_object
Date
The kernel may sleep under a write spinlock, and the function call path is:
cachefiles_mark_object_active (acquire the spinlock)
cachefiles_printk_object
kmalloc(GFP_NOIO) --> may sleep

To fix it, GFP_NOIO is replaced with GFP_ATOMIC.
This bug is found by my static analysis tool and my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
---
fs/cachefiles/namei.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index 3978b32..39e1504 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -83,7 +83,7 @@ static noinline void cachefiles_printk_object(struct cachefiles_object *object,
{
u8 *keybuf;

- keybuf = kmalloc(CACHEFILES_KEYBUF_SIZE, GFP_NOIO);
+ keybuf = kmalloc(CACHEFILES_KEYBUF_SIZE, GFP_ATOMIC);
if (object)
__cachefiles_printk_object(object, "", keybuf);
if (xobject)
--
1.7.9.5

\
 
 \ /
  Last update: 2017-10-09 05:02    [W:0.019 / U:0.312 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site