| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <72df399c-7e56-098d-f823-53cddd05ce9e@huaweicloud.com>
Date: Thu, 28 Sep 2023 11:40:18 +0800
From: Li Nan <linan666@...weicloud.com>
To: linan666@...weicloud.com, josef@...icpanda.com, axboe@...nel.dk
Cc: linux-block@...r.kernel.org, nbd@...er.debian.org,
linux-kernel@...r.kernel.org, yukuai3@...wei.com,
yi.zhang@...wei.com, houtao1@...wei.com, yangerkun@...wei.com
Subject: Re: [PATCH] nbd: pass nbd_sock to nbd_read_reply() instead of index
Friendly ping ...
在 2023/9/11 10:33, linan666@...weicloud.com 写道:
> From: Li Nan <linan122@...wei.com>
>
> If a socket is processing ioctl 'NBD_SET_SOCK', config->socks might be
> krealloc in nbd_add_socket(), and a garbage request is received now, a UAF
> may occurs.
>
> T1
> nbd_ioctl
> __nbd_ioctl
> nbd_add_socket
> blk_mq_freeze_queue
> T2
> recv_work
> nbd_read_reply
> sock_xmit
> krealloc config->socks
> def config->socks
>
> Pass nbd_sock to nbd_read_reply(). And introduce a new function
> sock_xmit_recv(), which differs from sock_xmit only in the way it get
> socket.
>
> ==================================================================
> BUG: KASAN: use-after-free in sock_xmit+0x525/0x550
> Read of size 8 at addr ffff8880188ec428 by task kworker/u12:1/18779
>
> Workqueue: knbd4-recv recv_work
> Call Trace:
> __dump_stack
> dump_stack+0xbe/0xfd
> print_address_description.constprop.0+0x19/0x170
> __kasan_report.cold+0x6c/0x84
> kasan_report+0x3a/0x50
> sock_xmit+0x525/0x550
> nbd_read_reply+0xfe/0x2c0
> recv_work+0x1c2/0x750
> process_one_work+0x6b6/0xf10
> worker_thread+0xdd/0xd80
> kthread+0x30a/0x410
> ret_from_fork+0x22/0x30
>
> Allocated by task 18784:
> kasan_save_stack+0x1b/0x40
> kasan_set_track
> set_alloc_info
> __kasan_kmalloc
> __kasan_kmalloc.constprop.0+0xf0/0x130
> slab_post_alloc_hook
> slab_alloc_node
> slab_alloc
> __kmalloc_track_caller+0x157/0x550
> __do_krealloc
> krealloc+0x37/0xb0
> nbd_add_socket
> +0x2d3/0x880
> __nbd_ioctl
> nbd_ioctl+0x584/0x8e0
> __blkdev_driver_ioctl
> blkdev_ioctl+0x2a0/0x6e0
> block_ioctl+0xee/0x130
> vfs_ioctl
> __do_sys_ioctl
> __se_sys_ioctl+0x138/0x190
> do_syscall_64+0x33/0x40
> entry_SYSCALL_64_after_hwframe+0x61/0xc6
>
> Freed by task 18784:
> kasan_save_stack+0x1b/0x40
> kasan_set_track+0x1c/0x30
> kasan_set_free_info+0x20/0x40
> __kasan_slab_free.part.0+0x13f/0x1b0
> slab_free_hook
> slab_free_freelist_hook
> slab_free
> kfree+0xcb/0x6c0
> krealloc+0x56/0xb0
> nbd_add_socket+0x2d3/0x880
> __nbd_ioctl
> nbd_ioctl+0x584/0x8e0
> __blkdev_driver_ioctl
> blkdev_ioctl+0x2a0/0x6e0
> block_ioctl+0xee/0x130
> vfs_ioctl
> __do_sys_ioctl
> __se_sys_ioctl+0x138/0x190
> do_syscall_64+0x33/0x40
> entry_SYSCALL_64_after_hwframe+0x61/0xc6
>
> Signed-off-by: Li Nan <linan122@...wei.com>
> ---
> drivers/block/nbd.c | 35 ++++++++++++++++++++++-------------
> 1 file changed, 22 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
> index a346dbd73543..712b2d164eed 100644
> --- a/drivers/block/nbd.c
> +++ b/drivers/block/nbd.c
> @@ -67,6 +67,7 @@ struct nbd_sock {
> struct recv_thread_args {
> struct work_struct work;
> struct nbd_device *nbd;
> + struct nbd_sock *nsock;
> int index;
> };
>
> @@ -490,15 +491,9 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req)
> return BLK_EH_DONE;
> }
>
> -/*
> - * Send or receive packet. Return a positive value on success and
> - * negtive value on failue, and never return 0.
> - */
> -static int sock_xmit(struct nbd_device *nbd, int index, int send,
> - struct iov_iter *iter, int msg_flags, int *sent)
> +static int __sock_xmit(struct nbd_device *nbd, struct socket *sock, int send,
> + struct iov_iter *iter, int msg_flags, int *sent)
> {
> - struct nbd_config *config = nbd->config;
> - struct socket *sock = config->socks[index]->sock;
> int result;
> struct msghdr msg;
> unsigned int noreclaim_flag;
> @@ -541,6 +536,19 @@ static int sock_xmit(struct nbd_device *nbd, int index, int send,
> return result;
> }
>
> +/*
> + * Send or receive packet. Return a positive value on success and
> + * negtive value on failure, and never return 0.
> + */
> +static int sock_xmit(struct nbd_device *nbd, int index, int send,
> + struct iov_iter *iter, int msg_flags, int *sent)
> +{
> + struct nbd_config *config = nbd->config;
> + struct socket *sock = config->socks[index]->sock;
> +
> + return __sock_xmit(nbd, sock, send, iter, msg_flags, sent);
> +}
> +
> /*
> * Different settings for sk->sk_sndtimeo can result in different return values
> * if there is a signal pending when we enter sendmsg, because reasons?
> @@ -697,7 +705,7 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
> return 0;
> }
>
> -static int nbd_read_reply(struct nbd_device *nbd, int index,
> +static int nbd_read_reply(struct nbd_device *nbd, struct socket *sock,
> struct nbd_reply *reply)
> {
> struct kvec iov = {.iov_base = reply, .iov_len = sizeof(*reply)};
> @@ -706,7 +714,7 @@ static int nbd_read_reply(struct nbd_device *nbd, int index,
>
> reply->magic = 0;
> iov_iter_kvec(&to, ITER_DEST, &iov, 1, sizeof(*reply));
> - result = sock_xmit(nbd, index, 0, &to, MSG_WAITALL, NULL);
> + result = __sock_xmit(nbd, sock, 0, &to, MSG_WAITALL, NULL);
> if (result < 0) {
> if (!nbd_disconnected(nbd->config))
> dev_err(disk_to_dev(nbd->disk),
> @@ -830,14 +838,14 @@ static void recv_work(struct work_struct *work)
> struct nbd_device *nbd = args->nbd;
> struct nbd_config *config = nbd->config;
> struct request_queue *q = nbd->disk->queue;
> - struct nbd_sock *nsock;
> + struct nbd_sock *nsock = args->nsock;
> struct nbd_cmd *cmd;
> struct request *rq;
>
> while (1) {
> struct nbd_reply reply;
>
> - if (nbd_read_reply(nbd, args->index, &reply))
> + if (nbd_read_reply(nbd, nsock->sock, &reply))
> break;
>
> /*
> @@ -872,7 +880,6 @@ static void recv_work(struct work_struct *work)
> percpu_ref_put(&q->q_usage_counter);
> }
>
> - nsock = config->socks[args->index];
> mutex_lock(&nsock->tx_lock);
> nbd_mark_nsock_dead(nbd, nsock, 1);
> mutex_unlock(&nsock->tx_lock);
> @@ -1216,6 +1223,7 @@ static int nbd_reconnect_socket(struct nbd_device *nbd, unsigned long arg)
> INIT_WORK(&args->work, recv_work);
> args->index = i;
> args->nbd = nbd;
> + args->nsock = nsock;
> nsock->cookie++;
> mutex_unlock(&nsock->tx_lock);
> sockfd_put(old);
> @@ -1398,6 +1406,7 @@ static int nbd_start_device(struct nbd_device *nbd)
> refcount_inc(&nbd->config_refs);
> INIT_WORK(&args->work, recv_work);
> args->nbd = nbd;
> + args->nsock = config->socks[i];
> args->index = i;
> queue_work(nbd->recv_workq, &args->work);
> }
--
Thanks,
Nan
Powered by blists - more mailing lists