From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 A42534F85CB; Tue, 13 Oct 2026 12:19:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791893994; cv=none; b=OY3E3IOVSQmgb2CDvarGqfqqWyqGkQBdBWVc4XGlMZdVCMU8SZC3vL/rlLN26MRvy7vfWWA3IYD7zSyCk/SEbp+/+v3bYayUEK/orQtTKjIxCONilVQL1Pvk6rE0kCrbq54UkAaXDo2hOekthxY/18I6zW5yQWSs0B4wx8TMulQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791893994; c=relaxed/simple; bh=FlOZXIXNCnC3j2TDupJCVIydOtsNlKohoEdidlyqhJU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mGXw58Us3W123CRMjnTNFq27otMoKapKeIXyjBzpm8i9VtxmyrG09r5JRzTpkjBycOSP4YZCiPy3pa1rvIfhQsQrMGlwnjXGSsQFl/VdvL1lRvdPgUBBPiIdONBRT0TrILGJU4KHYcWW3kAm3EQps38VNEyQIH160q1rZFdnnnA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=LSbjWi8D; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="LSbjWi8D" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06FF51F000FF; Tue, 13 Oct 2026 12:19:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1791893992; bh=qrgJKWIB/hDQAWLS7BLMoqpeh3i/UeS+OFeXE5ZR3jk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=LSbjWi8DWS8z3TrDNadlVj0UtmrJoH7BxO8OGupoQMwft6S10PXUSYFwFpcqX7KYU RZ7ovcy2gIB1y/puIqep5ct1eHRbGV3t9fS8nyUUZFHIweuBwwH2dVA1mnBe79wNth w9MHf+FpfVFq1Tl+RxKX4Sl/ZhuGQO4OUw47sbvs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Namjae Jeon , Sasha Levin Subject: [PATCH 6.18 411/621] ksmbd: safely discard unregistered deferred locks Date: Tue, 13 Oct 2026 13:36:46 +0200 Message-ID: <20261013112930.590102148@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261013112920.855194808@linuxfoundation.org> References: <20261013112920.855194808@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Namjae Jeon [ Upstream commit 054bcca4cd9f00719b01f7108b51a2168fb94f15 ] When vfs_lock_file() defers a lock, smb2_lock() puts its ksmbd_lock on rollback_list before allocating and registering the asynchronous work. If either operation fails, rollback assumes that smb_lock->conn is initialized and dereferences NULL. The deferred file_lock also remains linked into the VFS blocked-lock state while it is freed. Keep the lock off rollback_list until async setup succeeds. On setup failures, explicitly unblock and wake the deferred lock before freeing it and its ksmbd wrapper. Signed-off-by: Namjae Jeon Signed-off-by: Sasha Levin --- fs/smb/server/smb2pdu.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index 5e303942a7510..6860d5229e1a9 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -7562,6 +7562,13 @@ static void smb2_free_lock(struct file_lock *flock) locks_free_lock(flock); } +static void smb2_free_blocked_lock(struct file_lock *flock) +{ + ksmbd_vfs_posix_lock_unblock(flock); + locks_wake_up(flock); + locks_free_lock(flock); +} + static inline bool lock_defer_pending(struct file_lock *fl) { /* check pending lock waiters */ @@ -7804,11 +7811,12 @@ int smb2_lock(struct ksmbd_work *work) ksmbd_debug(SMB, "would have to wait for getting lock\n"); - list_add(&smb_lock->llist, &rollback_list); argv = kmalloc(sizeof(void *), KSMBD_DEFAULT_GFP); if (!argv) { err = -ENOMEM; + smb2_free_blocked_lock(flock); + kfree(smb_lock); goto out; } argv[0] = flock; @@ -7819,8 +7827,11 @@ int smb2_lock(struct ksmbd_work *work) if (rc) { kfree(argv); err = -ENOMEM; + smb2_free_blocked_lock(flock); + kfree(smb_lock); goto out; } + list_add(&smb_lock->llist, &rollback_list); spin_lock(&fp->f_lock); list_add(&work->fp_entry, &fp->blocked_works); spin_unlock(&fp->f_lock); -- 2.53.0