Ding Hui c7b8c2d06e SUNRPC: Fix UAF in svc_tcp_listen_data_ready() ... commit fc80fc2d4e upstream. After the listener svc_sock is freed, and before invoking svc_tcp_accept() for the established child sock, there is a window that the newsock retaining a freed listener svc_sock in sk_user_data which cloning from parent. In the race window, if data is received on the newsock, we will observe use-after-free report in svc_tcp_listen_data_ready(). Reproduce by two tasks: 1. while :; do rpc.nfsd 0 ; rpc.nfsd; done 2. while :; do echo "" | ncat -4 127.0.0.1 2049 ; done KASAN report: ================================================================== BUG: KASAN: slab-use-after-free in svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc] Read of size 8 at addr ffff888139d96228 by task nc/102553 CPU: 7 PID: 102553 Comm: nc Not tainted 6.3.0+ #18 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 Call Trace: <IRQ> dump_stack_lvl+0x33/0x50 print_address_description.constprop.0+0x27/0x310 print_report+0x3e/0x70 kasan_report+0xae/0xe0 svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc] tcp_data_queue+0x9f4/0x20e0 tcp_rcv_established+0x666/0x1f60 tcp_v4_do_rcv+0x51c/0x850 tcp_v4_rcv+0x23fc/0x2e80 ip_protocol_deliver_rcu+0x62/0x300 ip_local_deliver_finish+0x267/0x350 ip_local_deliver+0x18b/0x2d0 ip_rcv+0x2fb/0x370 __netif_receive_skb_one_core+0x166/0x1b0 process_backlog+0x24c/0x5e0 __napi_poll+0xa2/0x500 net_rx_action+0x854/0xc90 __do_softirq+0x1bb/0x5de do_softirq+0xcb/0x100 </IRQ> <TASK> ... </TASK> Allocated by task 102371: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 __kasan_kmalloc+0x7b/0x90 svc_setup_socket+0x52/0x4f0 [sunrpc] svc_addsock+0x20d/0x400 [sunrpc] __write_ports_addfd+0x209/0x390 [nfsd] write_ports+0x239/0x2c0 [nfsd] nfsctl_transaction_write+0xac/0x110 [nfsd] vfs_write+0x1c3/0xae0 ksys_write+0xed/0x1c0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc Freed by task 102551: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_save_free_info+0x2a/0x50 __kasan_slab_free+0x106/0x190 __kmem_cache_free+0x133/0x270 svc_xprt_free+0x1e2/0x350 [sunrpc] svc_xprt_destroy_all+0x25a/0x440 [sunrpc] nfsd_put+0x125/0x240 [nfsd] nfsd_svc+0x2cb/0x3c0 [nfsd] write_threads+0x1ac/0x2a0 [nfsd] nfsctl_transaction_write+0xac/0x110 [nfsd] vfs_write+0x1c3/0xae0 ksys_write+0xed/0x1c0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc Fix the UAF by simply doing nothing in svc_tcp_listen_data_ready() if state != TCP_LISTEN, that will avoid dereferencing svsk for all child socket. Link: https://lore.kernel.org/lkml/20230507091131.23540-1-dinghui@sangfor.com.cn/ Fixes: fa9251afc3 ("SUNRPC: Call the default socket callbacks instead of open coding") Signed-off-by: Ding Hui <dinghui@sangfor.com.cn> Cc: <stable@vger.kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-08-11 11:33:44 +02:00
..
auth_gss	SUNRPC: ensure the matching upcall is in-flight upon downcall	2023-01-18 09:26:40 +01:00
xprtrdma	xprtrdma: fix incorrect header size calculations	2022-06-25 11:46:45 +02:00
addr.c	net: sunrpc: interpret the return value of kstrtou32 correctly	2021-01-23 15:48:44 +01:00
auth.c
auth_generic.c	SUNRPC: Fix a bogus get/put in generic_key_to_expire()	2018-12-01 09:42:54 +01:00
auth_null.c
auth_unix.c
backchannel_rqst.c	SUNRPC: Reinitialise the backchannel request buffers before reuse	2022-08-25 11:11:32 +02:00
cache.c	sunrpc: fix crash when cache_head become valid before update	2019-12-17 20:40:00 +01:00
clnt.c	SUNRPC: remove the maximum number of retries in call_bind_status	2023-05-17 11:11:45 +02:00
debugfs.c
Kconfig
Makefile
netns.h
rpc_pipe.c	sunrpc: fixed rollback in rpc_gssd_dummy_populate()	2020-06-30 15:38:09 -04:00
rpcb_clnt.c	SUNRPC: stop printk reading past end of string	2020-09-23 10:46:34 +02:00
sched.c	SUNRPC: remove the maximum number of retries in call_bind_status	2023-05-17 11:11:45 +02:00
socklib.c
stats.c
sunrpc.h
sunrpc_syms.c
svc.c	sunrpc: fix refcount leak for rpc auth modules	2021-03-24 11:05:01 +01:00
svc_xprt.c	NFSD: Repair misuse of sv_lock in 5.10.16-rt30.	2021-03-24 11:05:00 +01:00
svcauth.c
svcauth_unix.c
svcsock.c	SUNRPC: Fix UAF in svc_tcp_listen_data_ready()	2023-08-11 11:33:44 +02:00
sysctl.c
timer.c
xdr.c	SUNRPC: Fix READ_PLUS crasher	2022-07-07 17:31:16 +02:00
xprt.c	SUNRPC: use _bh spinlocking on ->transport_lock	2022-09-15 12:23:53 +02:00
xprtmultipath.c
xprtsock.c	Revert "SUNRPC: attempt AF_LOCAL connect on setup"	2022-05-12 12:17:09 +02:00