queue-6.1/smb-client-fix-potential-uaf-in-smb2_is_valid_lease_break.patch

   1 From 705c76fbf726c7a2f6ff9143d4013b18daaaebf1 Mon Sep 17 00:00:00 2001
   2 From: Paulo Alcantara <pc@manguebit.com>
   3 Date: Tue, 2 Apr 2024 16:33:58 -0300
   4 Subject: smb: client: fix potential UAF in smb2_is_valid_lease_break()
   5
   6 From: Paulo Alcantara <pc@manguebit.com>
   7
   8 commit 705c76fbf726c7a2f6ff9143d4013b18daaaebf1 upstream.
   9
  10 Skip sessions that are being teared down (status == SES_EXITING) to
  11 avoid UAF.
  12
  13 Cc: stable@vger.kernel.org
  14 Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
  15 Signed-off-by: Steve French <stfrench@microsoft.com>
  16 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  17 ---
  18  fs/smb/client/smb2misc.c |    2 ++
  19  1 file changed, 2 insertions(+)
  20
  21 --- a/fs/smb/client/smb2misc.c
  22 +++ b/fs/smb/client/smb2misc.c
  23 @@ -622,6 +622,8 @@ smb2_is_valid_lease_break(char *buffer,
  24         /* look up tcon based on tid & uid */
  25         spin_lock(&cifs_tcp_ses_lock);
  26         list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
  27 +               if (cifs_ses_exiting(ses))
  28 +                       continue;
  29                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
  30                         spin_lock(&tcon->open_file_lock);
  31                         cifs_stats_inc(