smb: client: fix potential UAF in cifs_dump_full_key()

commit 58acd1f497 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Paulo Alcantara 2024-04-02 16:33:54 -03:00 committed by Greg Kroah-Hartman
parent 1e12f0d5c6
commit 3103163ccd

View file

@ -247,7 +247,9 @@ 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
@ -255,9 +257,11 @@ static int cifs_dump_full_key(struct cifs_tcon *tcon, struct smb3_full_key_debug
* so increment its refcount
*/
cifs_smb_ses_inc_refcount(ses);
spin_unlock(&ses_it->ses_lock);
found = true;
goto search_end;
}
spin_unlock(&ses_it->ses_lock);
}
}
search_end: