From c14cc63a63e94d490ac6517a555113c30d420db4 Mon Sep 17 00:00:00 2001 From: Ian Kent Date: Tue, 18 Jan 2011 12:06:04 +0800 Subject: [PATCH] autofs4 - fix get_next_positive_dentry() The initialization condition in fs/autofs4/expire.c:get_next_positive_dentry() appears to be incorrect. If prev == NULL I believe that root should be returned. Further down, at the current dentry check for it being simple_positive() it looks like the d_lock for dentry p should be dropped instead of dentry ret, otherwise when p is assinged to ret we end up with no lock on p and a lost lock on ret, which leads to a deadlock. Signed-off-by: Ian Kent Signed-off-by: Al Viro --- fs/autofs4/expire.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c index 3ed79d76c233..f43100b9662b 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -96,7 +96,7 @@ static struct dentry *get_next_positive_dentry(struct dentry *prev, struct dentry *p, *ret; if (prev == NULL) - return dget(prev); + return dget(root); spin_lock(&autofs4_lock); relock: @@ -133,7 +133,7 @@ again: spin_lock_nested(&ret->d_lock, DENTRY_D_LOCK_NESTED); /* Negative dentry - try next */ if (!simple_positive(ret)) { - spin_unlock(&ret->d_lock); + spin_unlock(&p->d_lock); p = ret; goto again; }