linux-kernel - Re: [syzbot] Re: [syzbot] [fs?] BUG: corrupted list in remove_wait

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] [day] [month] [year] [list]

Message-ID: <67b2e4af.050a0220.54b41.000e.GAE@google.com>
Date: Sun, 16 Feb 2025 23:26:39 -0800
From: syzbot <syzbot+4e21d5f67b886a692b55@...kaller.appspotmail.com>
To: linux-kernel@...r.kernel.org
Subject: Re: [syzbot] Re: [syzbot] [fs?] BUG: corrupted list in
 remove_wait_queue (2)

For archival purposes, forwarding an incoming command email to
linux-kernel@...r.kernel.org.

***

Subject: Re: [syzbot] [fs?] BUG: corrupted list in remove_wait_queue (2)
Author: lizhi.xu@...driver.com

#syz test

diff --git a/fs/select.c b/fs/select.c
index 7da531b1cf6b..63dd2fb58447 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -977,6 +977,7 @@ static int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds,
  	struct poll_list *walk = head;
 	unsigned int todo = nfds;
 	unsigned int len;
+	static DEFINE_MUTEX(syspoll_lock);
 
 	if (nfds > rlimit(RLIMIT_NOFILE))
 		return -EINVAL;
@@ -1005,9 +1006,11 @@ static int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds,
 		}
 	}
 
+	mutex_lock(&syspoll_lock);
 	poll_initwait(&table);
 	fdcount = do_poll(head, &table, end_time);
 	poll_freewait(&table);
+	mutex_unlock(&syspoll_lock);
 
 	if (!user_write_access_begin(ufds, nfds * sizeof(*ufds)))
 		goto out_fds;