From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A2C83FC06; Mon, 11 Dec 2023 18:44:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="MsrivVyg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2566EC433C7; Mon, 11 Dec 2023 18:44:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1702320264; bh=yUCW42Cec3hFQtdfAWJ7LvqMkC8qsxVevIUAz0H/ziA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MsrivVyg+lzpt498JeOIn7aJYgcYFievRwjb+aaUoM6q9e6MZoZGZKiymQn5EE+Zr 7grygfq3zL/vSIsi8/JYs1GHPGqbusKKSNoGBPoc5qq7RzdXh6vP83F9Z2ufnwgPst 1A9bN2xFRee2ncq5WHCmLY4/eX2/127P0vvLetAQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Robert Morris , "Paulo Alcantara (SUSE)" , Steve French , Sasha Levin Subject: [PATCH 5.4 65/67] smb: client: fix potential NULL deref in parse_dfs_referrals() Date: Mon, 11 Dec 2023 19:22:49 +0100 Message-ID: <20231211182017.778953860@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231211182015.049134368@linuxfoundation.org> References: <20231211182015.049134368@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paulo Alcantara [ Upstream commit 92414333eb375ed64f4ae92d34d579e826936480 ] If server returned no data for FSCTL_DFS_GET_REFERRALS, @dfs_rsp will remain NULL and then parse_dfs_referrals() will dereference it. Fix this by returning -EIO when no output data is returned. Besides, we can't fix it in SMB2_ioctl() as some FSCTLs are allowed to return no data as per MS-SMB2 2.2.32. Fixes: 9d49640a21bf ("CIFS: implement get_dfs_refer for SMB2+") Cc: stable@vger.kernel.org Reported-by: Robert Morris Signed-off-by: Paulo Alcantara (SUSE) Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/cifs/smb2ops.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index ad9b207432e10..5fea15a5f3419 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -2498,6 +2498,8 @@ smb2_get_dfs_refer(const unsigned int xid, struct cifs_ses *ses, (char **)&dfs_rsp, &dfs_rsp_size); } while (rc == -EAGAIN); + if (!rc && !dfs_rsp) + rc = -EIO; if (rc) { if ((rc != -ENOENT) && (rc != -EOPNOTSUPP)) cifs_tcon_dbg(VFS, "ioctl error in %s rc=%d\n", __func__, rc); -- 2.42.0