[PATCH 4.9 37/39] do_epoll_ctl(): clean the failure exits up a bit

From: Greg Kroah-Hartman
Date: Mon Aug 24 2020 - 04:52:51 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

commit 52c479697c9b73f628140dcdfcd39ea302d05482 upstream.

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/eventpoll.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1946,10 +1946,8 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, in
mutex_lock(&epmutex);
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,
@@ -1978,8 +1976,6 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, in
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)
@@ -2002,8 +1998,10 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, in
mutex_unlock(&ep->mtx);

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

fdput(tf);
error_fput: