kernel/git/stable/linux.git/net/tls, branch linux-4.16.y

tls: fix use-after-free in tls_push_record

2018-06-25T23:53:55+00:00

[ Upstream commit a447da7d00410278c90d3576782a43f8b675d7be ] syzkaller managed to trigger a use-after-free in tls like the following: BUG: KASAN: use-after-free in tls_push_record.constprop.15+0x6a2/0x810 [tls] Write of size 1 at addr ffff88037aa08000 by task a.out/2317 CPU: 3 PID: 2317 Comm: a.out Not tainted 4.17.0+ #144 Hardware name: LENOVO 20FBCTO1WW/20FBCTO1WW, BIOS N1FET47W (1.21 ) 11/28/2016 Call Trace: dump_stack+0x71/0xab print_address_description+0x6a/0x280 kasan_report+0x258/0x380 ? tls_push_record.constprop.15+0x6a2/0x810 [tls] tls_push_record.constprop.15+0x6a2/0x810 [tls] tls_sw_push_pending_record+0x2e/0x40 [tls] tls_sk_proto_close+0x3fe/0x710 [tls] ? tcp_check_oom+0x4c0/0x4c0 ? tls_write_space+0x260/0x260 [tls] ? kmem_cache_free+0x88/0x1f0 inet_release+0xd6/0x1b0 __sock_release+0xc0/0x240 sock_close+0x11/0x20 __fput+0x22d/0x660 task_work_run+0x114/0x1a0 do_exit+0x71a/0x2780 ? mm_update_next_owner+0x650/0x650 ? handle_mm_fault+0x2f5/0x5f0 ? __do_page_fault+0x44f/0xa50 ? mm_fault_error+0x2d0/0x2d0 do_group_exit+0xde/0x300 __x64_sys_exit_group+0x3a/0x50 do_syscall_64+0x9a/0x300 ? page_fault+0x8/0x30 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This happened through fault injection where aead_req allocation in tls_do_encryption() eventually failed and we returned -ENOMEM from the function. Turns out that the use-after-free is triggered from tls_sw_sendmsg() in the second tls_push_record(). The error then triggers a jump to waiting for memory in sk_stream_wait_memory() resp. returning immediately in case of MSG_DONTWAIT. What follows is the trim_both_sgl(sk, orig_size), which drops elements from the sg list added via tls_sw_sendmsg(). Now the use-after-free gets triggered when the socket is being closed, where tls_sk_proto_close() callback is invoked. The tls_complete_pending_work() will figure that there's a pending closed tls record to be flushed and thus calls into the tls_push_pending_closed_record() from there. ctx->push_pending_record() is called from the latter, which is the tls_sw_push_pending_record() from sw path. This again calls into tls_push_record(). And here the tls_fill_prepend() will panic since the buffer address has been freed earlier via trim_both_sgl(). One way to fix it is to move the aead request allocation out of tls_do_encryption() early into tls_push_record(). This means we don't prep the tls header and advance state to the TLS_PENDING_CLOSED_RECORD before allocation which could potentially fail happened. That fixes the issue on my side. Fixes: 3c4d7559159b ("tls: kernel TLS support") Reported-by: syzbot+5c74af81c547738e1684@syzkaller.appspotmail.com Reported-by: syzbot+709f2810a6a05f11d4d3@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann Acked-by: Dave Watson Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net/tls: Fix connection stall on partial tls record

2018-05-19T08:19:32+00:00

[ Upstream commit 080324c36ade319f57e505633ab54f6f53289b45 ] In the case of writing a partial tls record we forgot to clear the ctx->in_tcp_sendpages flag, causing some connections to stall. Fixes: c212d2c7fc47 ("net/tls: Don't recursively call push_record during tls_write_space callbacks") Signed-off-by: Andre Tomt Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net/tls: Don't recursively call push_record during tls_write_space callbacks

2018-05-19T08:19:32+00:00

[ Upstream commit c212d2c7fc4736d49be102fb7a1a545cdc2f1fea ] It is reported that in some cases, write_space may be called in do_tcp_sendpages, such that we recursively invoke do_tcp_sendpages again: [ 660.468802] ? do_tcp_sendpages+0x8d/0x580 [ 660.468826] ? tls_push_sg+0x74/0x130 [tls] [ 660.468852] ? tls_push_record+0x24a/0x390 [tls] [ 660.468880] ? tls_write_space+0x6a/0x80 [tls] ... tls_push_sg already does a loop over all sending sg's, so ignore any tls_write_space notifications until we are done sending. We then have to call the previous write_space to wake up poll() waiters after we are done with the send loop. Reported-by: Andre Tomt Signed-off-by: Dave Watson Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tls: Use correct sk->sk_prot for IPV6

2018-02-27T19:41:48+00:00

The tls ulp overrides sk->prot with a new tls specific proto structs. The tls specific structs were previously based on the ipv4 specific tcp_prot sturct. As a result, attaching the tls ulp to an ipv6 tcp socket replaced some ipv6 callback with the ipv4 equivalents. This patch adds ipv6 tls proto structs and uses them when attached to ipv6 sockets. Fixes: 3c4d7559159b ('tls: kernel TLS support') Signed-off-by: Boris Pismenny Signed-off-by: Ilya Lesokhin Signed-off-by: David S. Miller

tls: getsockopt return record sequence number

2018-02-14T20:05:19+00:00

Return the TLS record sequence number in getsockopt. Signed-off-by: Boris Pismenny Signed-off-by: David S. Miller

tls: reset the crypto info if copy_from_user fails

2018-02-14T20:05:19+00:00

copy_from_user could copy some partial information, as a result TLS_CRYPTO_INFO_READY(crypto_info) could be true while crypto_info is using uninitialzed data. This patch resets crypto_info when copy_from_user fails. fixes: 3c4d7559159b ("tls: kernel TLS support") Signed-off-by: Boris Pismenny Signed-off-by: David S. Miller

tls: retrun the correct IV in getsockopt

2018-02-14T20:05:19+00:00

Current code returns four bytes of salt followed by four bytes of IV. This patch returns all eight bytes of IV. fixes: 3c4d7559159b ("tls: kernel TLS support") Signed-off-by: Boris Pismenny Signed-off-by: David S. Miller

net: add a UID to use for ULP socket assignment

2018-02-06T10:39:31+00:00

Create a UID field and enum that can be used to assign ULPs to sockets. This saves a set of string comparisons if the ULP id is known. For sockmap, which is added in the next patches, a ULP is used to hook into TCP sockets close state. In this case the ULP being added is done at map insert time and the ULP is known and done on the kernel side. In this case the named lookup is not needed. Because we don't want to expose psock internals to user space socket options a user visible flag is also added. For TLS this is set for BPF it will be cleared. Alos remove pr_notice, user gets an error code back and should check that rather than rely on logs. Signed-off-by: John Fastabend Signed-off-by: Daniel Borkmann

tls: Add support for encryption using async offload accelerator

2018-01-31T15:26:30+00:00

Async crypto accelerators (e.g. drivers/crypto/caam) support offloading GCM operation. If they are enabled, crypto_aead_encrypt() return error code -EINPROGRESS. In this case tls_do_encryption() needs to wait on a completion till the time the response for crypto offload request is received. Signed-off-by: Vakul Garg Signed-off-by: David S. Miller

tls: Correct length of scatterlist in tls_sw_sendpage

2018-01-22T21:25:21+00:00

The scatterlist is reused by both sendmsg and sendfile. If a sendmsg of smaller number of pages is followed by a sendfile of larger number of pages, the scatterlist may be too short, resulting in a crash in gcm_encrypt. Add sg_unmark_end to make the list the correct length. tls_sw_sendmsg already calls sg_unmark_end correctly when it allocates memory in alloc_sg, or in zerocopy_from_iter. Signed-off-by: Dave Watson Signed-off-by: David S. Miller