From: Paulo Alcantara <pc@xxxxxxxxxxxxx>
[ Upstream commit 58acd1f497162e7d282077f816faa519487be045 ]
Skip sessions that are being teared down (status == SES_EXITING) to
avoid UAF.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Paulo Alcantara (Red Hat) <pc@xxxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Jianqi Ren <jianqi.ren.cn@xxxxxxxxxxxxx>
---
fs/smb/client/ioctl.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/fs/smb/client/ioctl.c b/fs/smb/client/ioctl.c
index ae9905e2b9d4..7402070b7a06 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:
--
2.25.1
