linux-cifs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ronnie Sahlberg <lsahlber@redhat.com>
To: linux-cifs <linux-cifs@vger.kernel.org>
Cc: Steve French <smfrench@gmail.com>, Ronnie Sahlberg <lsahlber@redhat.com>
Subject: [PATCH] cifs: fix panic in smb2_reconnect
Date: Mon,  3 Jun 2019 17:31:38 +1000	[thread overview]
Message-ID: <20190603073138.25211-1-lsahlber@redhat.com> (raw)

RH Bugzilla: 1702264

We need to protect so that the call to smb2_reconnect() in
smb2_reconnect_server() does not end up freeing the session
because it can lead to a use after free and crash.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
---
 fs/cifs/smb2pdu.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 565b60b62f4d..c4f3e2403b58 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -3116,6 +3116,7 @@ void smb2_reconnect_server(struct work_struct *work)
 		if (ses->tcon_ipc && ses->tcon_ipc->need_reconnect) {
 			list_add_tail(&ses->tcon_ipc->rlist, &tmp_list);
 			tcon_exist = true;
+			ses->ses_count++;
 		}
 	}
 	/*
@@ -3134,6 +3135,8 @@ void smb2_reconnect_server(struct work_struct *work)
 		else
 			resched = true;
 		list_del_init(&tcon->rlist);
+		if (tcon->ipc)
+			cifs_put_smb_ses(tcon->ses);
 		cifs_put_tcon(tcon);
 	}
 
-- 
2.13.6


             reply	other threads:[~2019-06-03  7:31 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-03  7:31 Ronnie Sahlberg [this message]
2019-06-03 10:00 ` [PATCH] cifs: fix panic in smb2_reconnect Aurélien Aptel
2019-06-05  0:15 Ronnie Sahlberg
2019-06-05  0:21 ` Steve French
2019-06-11 23:52 ` Pavel Shilovsky

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190603073138.25211-1-lsahlber@redhat.com \
    --to=lsahlber@redhat.com \
    --cc=linux-cifs@vger.kernel.org \
    --cc=smfrench@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).