From d3da25c5ac84430f89875ca7485a3828150a7e0a Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <pc@manguebit.com>
Date: Tue, 2 Apr 2024 16:33:55 -0300
Subject: [PATCH] smb: client: fix potential UAF in cifs_stats_proc_write()

Skip sessions that are being teared down (status == SES_EXITING) to
avoid UAF.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
---
 fs/smb/client/cifs_debug.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/smb/client/cifs_debug.c b/fs/smb/client/cifs_debug.c
index c9aec9a38ad3..8535c9907462 100644
--- a/fs/smb/client/cifs_debug.c
+++ b/fs/smb/client/cifs_debug.c
@@ -678,6 +678,8 @@ static ssize_t cifs_stats_proc_write(struct file *file,
 			}
 #endif /* CONFIG_CIFS_STATS2 */
 			list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+				if (cifs_ses_exiting(ses))
+					continue;
 				list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 					atomic_set(&tcon->num_smbs_sent, 0);
 					spin_lock(&tcon->stat_lock);