From 99d84d4330e8a67abfab77edb985db18aa603921 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 22 Aug 2020 23:08:37 -0400 Subject: [PATCH] untangling ep_call_nested(): move push/pop of cookie into the callbacks Signed-off-by: Al Viro --- fs/eventpoll.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/fs/eventpoll.c b/fs/eventpoll.c index bd2cc78c47c8..9a6ee5991f3d 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -455,15 +455,7 @@ static bool ep_push_nested(void *cookie) static int ep_call_nested(int (*nproc)(void *, void *, int), void *priv, void *cookie) { - int error; - - if (!ep_push_nested(cookie)) - return -1; - /* Call the nested function */ - error = (*nproc)(priv, cookie, nesting - 1); - nesting--; - - return error; + return (*nproc)(priv, cookie, nesting); } /* @@ -1340,6 +1332,9 @@ static int reverse_path_check_proc(void *priv, void *cookie, int call_nests) struct file *child_file; struct epitem *epi; + if (!ep_push_nested(cookie)) /* limits recursion */ + return -1; + /* CTL_DEL can remove links here, but that can't increase our count */ rcu_read_lock(); list_for_each_entry_rcu(epi, &file->f_ep_links, fllink) { @@ -1362,6 +1357,7 @@ static int reverse_path_check_proc(void *priv, void *cookie, int call_nests) } } rcu_read_unlock(); + nesting--; /* pop */ return error; } @@ -1913,6 +1909,9 @@ static int ep_loop_check_proc(void *priv, void *cookie, int call_nests) struct rb_node *rbp; struct epitem *epi; + if (!ep_push_nested(cookie)) /* limits recursion */ + return -1; + mutex_lock_nested(&ep->mtx, call_nests + 1); ep->gen = loop_check_gen; for (rbp = rb_first_cached(&ep->rbr); rbp; rbp = rb_next(rbp)) { @@ -1942,6 +1941,7 @@ static int ep_loop_check_proc(void *priv, void *cookie, int call_nests) } } mutex_unlock(&ep->mtx); + nesting--; /* pop */ return error; }