From f4a60d360d9114b5085701a3702a0102b0d6d846 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Tue, 2 Apr 2024 16:33:54 -0300 Subject: [PATCH] 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) Signed-off-by: Steve French Signed-off-by: Jianqi Ren Signed-off-by: He Zhe Signed-off-by: Greg Kroah-Hartman --- 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: