From: Li Zefan <lizefan@huawei.com>
Date: Wed, 12 Feb 2014 20:44:57 +0000 (-0800)
Subject: jffs2: remove from wait queue after schedule()
X-Git-Tag: firefly_0821_release~176^2~4119^2~84
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=3ead9578443b66ddb3d50ed4f53af8a0c0298ec5;p=firefly-linux-kernel-4.4.55.git

jffs2: remove from wait queue after schedule()

@wait is a local variable, so if we don't remove it from the wait queue
list, later wake_up() may end up accessing invalid memory.

This was spotted by eyes.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
---

diff --git a/fs/jffs2/nodemgmt.c b/fs/jffs2/nodemgmt.c
index 03310721712f..bbae5b1a833a 100644
--- a/fs/jffs2/nodemgmt.c
+++ b/fs/jffs2/nodemgmt.c
@@ -179,6 +179,7 @@ int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
 					spin_unlock(&c->erase_completion_lock);
 
 					schedule();
+					remove_wait_queue(&c->erase_wait, &wait);
 				} else
 					spin_unlock(&c->erase_completion_lock);
 			} else if (ret)