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 DA074369204; Mon, 23 Mar 2026 14:20:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774275643; cv=none; b=iK6W9Q3GTzlE9J+UOgf+9FEVSYbW8Ofn/+XqNQZUbvmk7Gzil9EjrfyYAotswthicMgamOwIZeW0lJr1r105/L5N8KBtxj7Ypp9q//Acn5UJYZik4L0iBEXJD2dyH4jwIqDv2t8giecMdPkOXS/+SJ2a2Lg9KPpGcpXXWlct94I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774275643; c=relaxed/simple; bh=1kZq8OIeBXOp7N1jcXLHXSS6LJBghEdnYeFbw20EL/w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jy+6yoSvUCaKnG3tuX41jLi0igNKA6k9Z7wqG6ycmvNMnQUCMpDkgAgNrQmPlwb32qxKn241zlHvK9cB87B/LbxFdu/RjEnRDlcJwI/O+ajtgm/DFFZXpVZ29+0BZXkEmzLXc9J4pbWRh4S2mh7txSJBKGHGRUIpyJm4V4vPjf4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XfziB0RC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="XfziB0RC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5C95BC4CEF7; Mon, 23 Mar 2026 14:20:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1774275643; bh=1kZq8OIeBXOp7N1jcXLHXSS6LJBghEdnYeFbw20EL/w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XfziB0RCFzz3iNbUq8u5gQCZFWm3MJoWLOOCh33l7FHzl9KskKIVM8LR6qXzGVOK4 ueI3HZwIDq6D71gAsxNqTnpv5mDAQzC53UG/R0YjDfbCviykdl8p+NQkZh3sZVXWv9 QGn1qqhDa7dL2oUvabtcHknaRZxfmBpLX5apbE7Y= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Namjae Jeon , Steve French Subject: [PATCH 6.12 170/460] ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() Date: Mon, 23 Mar 2026 14:42:46 +0100 Message-ID: <20260323134530.719980912@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260323134526.647552166@linuxfoundation.org> References: <20260323134526.647552166@linuxfoundation.org> User-Agent: quilt/0.69 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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Namjae Jeon commit eac3361e3d5dd8067b3258c69615888eb45e9f25 upstream. opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being accessed after rcu_read_unlock() has been called. This creates a race condition where the memory could be freed by a concurrent writer between the unlock and the subsequent pointer dereferences (opinfo->is_lease, etc.), leading to a use-after-free. Fixes: 5fb282ba4fef ("ksmbd: fix possible null-deref in smb_lazy_parent_lease_break_close") Cc: stable@vger.kernel.org Signed-off-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/smb/server/oplock.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/fs/smb/server/oplock.c +++ b/fs/smb/server/oplock.c @@ -1123,10 +1123,12 @@ void smb_lazy_parent_lease_break_close(s rcu_read_lock(); opinfo = rcu_dereference(fp->f_opinfo); - rcu_read_unlock(); - if (!opinfo || !opinfo->is_lease || opinfo->o_lease->version != 2) + if (!opinfo || !opinfo->is_lease || opinfo->o_lease->version != 2) { + rcu_read_unlock(); return; + } + rcu_read_unlock(); p_ci = ksmbd_inode_lookup_lock(fp->filp->f_path.dentry->d_parent); if (!p_ci)