[PATCH 5.8 148/148] do_epoll_ctl(): clean the failure exits up a bit

Greg Kroah-Hartman
2020-08-24T08:38:50Z

From: Al Viro <viro@zeniv.linux.org.uk>

commit 52c479697c9b73f628140dcdfcd39ea302d05482 upstream.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/eventpoll.c | 19 ++++++-------------
1 file changed, 6 insertions(+), 13 deletions(-)

--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -2203,29 +2203,22 @@ int do_epoll_ctl(int epfd, int op, int f
full_check = 1;
if (is_file_epoll(tf.file)) {
error = -ELOOP;
- if (ep_loop_check(ep, tf.file) != 0) {
- clear_tfile_check_list();
+ if (ep_loop_check(ep, tf.file) != 0)
goto error_tgt_fput;
- }
} else {
get_file(tf.file);
list_add(&tf.file->f_tfile_llink,
&tfile_check_list);
}
error = epoll_mutex_lock(&ep->mtx, 0, nonblock);
- if (error) {
-out_del:
- list_del(&tf.file->f_tfile_llink);
- if (!is_file_epoll(tf.file))
- fput(tf.file);
+ if (error)
goto error_tgt_fput;
- }
if (is_file_epoll(tf.file)) {
tep = tf.file->private_data;
error = epoll_mutex_lock(&tep->mtx, 1, nonblock);
if (error) {
mutex_unlock(&ep->mtx);
- goto out_del;
+ goto error_tgt_fput;
}
}
}
@@ -2246,8 +2239,6 @@ out_del:
error = ep_insert(ep, epds, tf.file, fd, full_check);
} else
error = -EEXIST;
- if (full_check)
- clear_tfile_check_list();
break;
case EPOLL_CTL_DEL:
if (epi)
@@ -2270,8 +2261,10 @@ out_del:
mutex_unlock(&ep->mtx);

error_tgt_fput:
- if (full_check)
+ if (full_check) {
+ clear_tfile_check_list();
mutex_unlock(&epmutex);
+ }

fdput(tf);