don't bugger nd->seq on set_root_rcu() from follow_dotdot_rcu()
authorAl Viro <viro@zeniv.linux.org.uk>
Sun, 14 Sep 2014 01:55:46 +0000 (21:55 -0400)
committerAl Viro <viro@zeniv.linux.org.uk>
Sun, 14 Sep 2014 18:19:44 +0000 (14:19 -0400)
commit7bd88377d482e1eae3c5329b12e33cfd664fa6a9
tree814293d29b98c33b887c3140c11e24ccffbf9862
parentf5be3e29127aec8c87f883aadadff337f8c2cfd7
don't bugger nd->seq on set_root_rcu() from follow_dotdot_rcu()

return the value instead, and have path_init() do the assignment.  Broken by
"vfs: Fix absolute RCU path walk failures due to uninitialized seq number",
which was Cc-stable with 2.6.38+ as destination.  This one should go where
it went.

To avoid dummy value returned in case when root is already set (it would do
no harm, actually, since the only caller that doesn't ignore the return value
is guaranteed to have nd->root *not* set, but it's more obvious that way),
lift the check into callers.  And do the same to set_root(), to keep them
in sync.

Cc: stable@vger.kernel.org # 2.6.38+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
fs/namei.c