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 873AB134A4 for ; Mon, 12 Jun 2023 10:44:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0DF96C433EF; Mon, 12 Jun 2023 10:44:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1686566695; bh=k+8h8SGvjs4mVpgQP+Iz9GTT9FbZaJrXgF70gd/xD7w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bp+OrDFTC5AQgJJN8h0fWMSi45IqxFOUSlSXCntFioKNlaILWNCI7dmgTECFqHbjV yHBqUB5zU/d/Gi6cfaQ60EwHeXfR8q8WnTVVOaHt/ZkE/npyZxPn5dPm9vE5lBJI8f 8HQOzDZmeDiaATsTn2CJfOoM43oTI4qtXQkgMkL0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Xie Yongji" , Xianjun Zeng , Sheng Zhao , "Michael S. Tsirkin" , Jason Wang , Sasha Levin Subject: [PATCH 6.1 122/132] vduse: avoid empty string for dev name Date: Mon, 12 Jun 2023 12:27:36 +0200 Message-ID: <20230612101715.780565122@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230612101710.279705932@linuxfoundation.org> References: <20230612101710.279705932@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Sheng Zhao [ Upstream commit a90e8608eb0ed93d31ac0feb055f77ce59512542 ] Syzkaller hits a kernel WARN when the first character of the dev name provided is NULL. Solution is to add a NULL check before calling cdev_device_add() in vduse_create_dev(). kobject: (0000000072042169): attempted to be registered with empty name! WARNING: CPU: 0 PID: 112695 at lib/kobject.c:236 Call Trace: kobject_add_varg linux/src/lib/kobject.c:390 [inline] kobject_add+0xf6/0x150 linux/src/lib/kobject.c:442 device_add+0x28f/0xc20 linux/src/drivers/base/core.c:2167 cdev_device_add+0x83/0xc0 linux/src/fs/char_dev.c:546 vduse_create_dev linux/src/drivers/vdpa/vdpa_user/vduse_dev.c:2254 [inline] vduse_ioctl+0x7b5/0xf30 linux/src/drivers/vdpa/vdpa_user/vduse_dev.c:2316 vfs_ioctl linux/src/fs/ioctl.c:47 [inline] file_ioctl linux/src/fs/ioctl.c:510 [inline] do_vfs_ioctl+0x14b/0xa80 linux/src/fs/ioctl.c:697 ksys_ioctl+0x7c/0xa0 linux/src/fs/ioctl.c:714 __do_sys_ioctl linux/src/fs/ioctl.c:721 [inline] __se_sys_ioctl linux/src/fs/ioctl.c:719 [inline] __x64_sys_ioctl+0x42/0x50 linux/src/fs/ioctl.c:719 do_syscall_64+0x94/0x330 linux/src/arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace") Cc: "Xie Yongji" Reported-by: Xianjun Zeng Signed-off-by: Sheng Zhao Message-Id: <20230530033626.1266794-1-sheng.zhao@bytedance.com> Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang Reviewed-by: Xie Yongji Cc: "Michael S. Tsirkin", "Jason Wang", Reviewed-by: Xie Yongji Signed-off-by: Sasha Levin --- drivers/vdpa/vdpa_user/vduse_dev.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index 31017ebc4d7c7..72f924ec4658d 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1443,6 +1443,9 @@ static bool vduse_validate_config(struct vduse_dev_config *config) if (config->vq_num > 0xffff) return false; + if (!config->name[0]) + return false; + if (!device_is_allowed(config->device_id)) return false; -- 2.39.2