From: Paulo Alcantara <pc@manguebit.com>
Date: Tue, 2 Apr 2024 19:33:54 +0000 (-0300)
Subject: smb: client: fix potential UAF in cifs_dump_full_key()
X-Git-Tag: v6.1.132~53
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f4a60d360d9114b5085701a3702a0102b0d6d846;p=thirdparty%2Fkernel%2Fstable.git

smb: client: fix potential UAF in cifs_dump_full_key()

commit 58acd1f497162e7d282077f816faa519487be045 upstream.

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>
Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/smb/client/ioctl.c b/fs/smb/client/ioctl.c
index ae9905e2b9d4a..7402070b7a061 100644
--- a/fs/smb/client/ioctl.c
+++ b/fs/smb/client/ioctl.c
@@ -246,7 +246,9 @@ static int cifs_dump_full_key(struct cifs_tcon *tcon, struct smb3_full_key_debug
 		spin_lock(&cifs_tcp_ses_lock);
 		list_for_each_entry(server_it, &cifs_tcp_ses_list, tcp_ses_list) {
 			list_for_each_entry(ses_it, &server_it->smb_ses_list, smb_ses_list) {
-				if (ses_it->Suid == out.session_id) {
+				spin_lock(&ses_it->ses_lock);
+				if (ses_it->ses_status != SES_EXITING &&
+				    ses_it->Suid == out.session_id) {
 					ses = ses_it;
 					/*
 					 * since we are using the session outside the crit
@@ -254,9 +256,11 @@ static int cifs_dump_full_key(struct cifs_tcon *tcon, struct smb3_full_key_debug
 					 * so increment its refcount
 					 */
 					ses->ses_count++;
+					spin_unlock(&ses_it->ses_lock);
 					found = true;
 					goto search_end;
 				}
+				spin_unlock(&ses_it->ses_lock);
 			}
 		}
 search_end: