linux-kernel - [PATCH 5.7 123/124] do_epoll_ctl(): clean the failure exits up a bit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 24 Aug 2020 10:30:57 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Al Viro <viro@...iv.linux.org.uk>
Subject: [PATCH 5.7 123/124] do_epoll_ctl(): clean the failure exits up a bit

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

commit 52c479697c9b73f628140dcdfcd39ea302d05482 upstream.

Signed-off-by: Al Viro <viro@...iv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.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);
 error_fput: