From: Al Viro <viro@zeniv.linux.org.uk>
Date: Mon, 25 Jul 2011 18:15:50 +0000 (-0400)
Subject: fix devtmpfs race
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e13889bab3c6b5c839075086d28fe05f71984dda;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git

fix devtmpfs race

After we's done complete(&req->done), there's nothing to prevent the
scope containing *req from being gone and *req overwritten by any
kind of junk.  So we must read req->next before that...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
index 6d678c99512e..b89fffc1d777 100644
--- a/drivers/base/devtmpfs.c
+++ b/drivers/base/devtmpfs.c
@@ -406,9 +406,10 @@ static int devtmpfsd(void *p)
 			requests = NULL;
 			spin_unlock(&req_lock);
 			while (req) {
+				struct req *next = req->next;
 				req->err = handle(req->name, req->mode, req->dev);
 				complete(&req->done);
-				req = req->next;
+				req = next;
 			}
 			spin_lock(&req_lock);
 		}