kernel/linux.git/include/net/tls.h, branch v5.10.86

net/tls: Fix flipped sign in tls_err_abort() calls

2021-11-02T18:48:19+00:00

commit da353fac65fede6b8b4cfe207f0d9408e3121105 upstream. sk->sk_err appears to expect a positive value, a convention that ktls doesn't always follow and that leads to memory corruption in other code. For instance, [kworker] tls_encrypt_done(..., err=) tls_err_abort(.., err) sk->sk_err = err; [task] splice_from_pipe_feed ... tls_sw_do_sendpage if (sk->sk_err) { ret = -sk->sk_err; // ret is positive splice_from_pipe_feed (continued) ret = actor(...) // ret is still positive and interpreted as bytes // written, resulting in underflow of buf->len and // sd->len, leading to huge buf->offset and bogus // addresses computed in later calls to actor() Fix all tls_err_abort() callers to pass a negative error code consistently and centralize the error-prone sign flip there, throwing in a warning to catch future misuse and uninlining the function so it really does only warn once. Cc: stable@vger.kernel.org Fixes: c46234ebb4d1e ("tls: RX path for ktls") Reported-by: syzbot+b187b77c8474f9648fae@syzkaller.appspotmail.com Signed-off-by: Daniel Jordan Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net/tls: Fix use-after-free after the TLS device goes down and up

2021-06-10T11:39:18+00:00

[ Upstream commit c55dcdd435aa6c6ad6ccac0a4c636d010ee367a4 ] When a netdev with active TLS offload goes down, tls_device_down is called to stop the offload and tear down the TLS context. However, the socket stays alive, and it still points to the TLS context, which is now deallocated. If a netdev goes up, while the connection is still active, and the data flow resumes after a number of TCP retransmissions, it will lead to a use-after-free of the TLS context. This commit addresses this bug by keeping the context alive until its normal destruction, and implements the necessary fallbacks, so that the connection can resume in software (non-offloaded) kTLS mode. On the TX side tls_sw_fallback is used to encrypt all packets. The RX side already has all the necessary fallbacks, because receiving non-decrypted packets is supported. The thing needed on the RX side is to block resync requests, which are normally produced after receiving non-decrypted packets. The necessary synchronization is implemented for a graceful teardown: first the fallbacks are deployed, then the driver resources are released (it used to be possible to have a tls_dev_resync after tls_dev_del). A new flag called TLS_RX_DEV_DEGRADED is added to indicate the fallback mode. It's used to skip the RX resync logic completely, as it becomes useless, and some objects may be released (for example, resync_async, which is allocated and freed by the driver). Fixes: e8f69799810c ("net/tls: Add generic NIC offload infrastructure") Signed-off-by: Maxim Mikityanskiy Reviewed-by: Tariq Toukan Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net/tls: Replace TLS_RX_SYNC_RUNNING with RCU

2021-06-10T11:39:17+00:00

[ Upstream commit 05fc8b6cbd4f979a6f25759c4a17dd5f657f7ecd ] RCU synchronization is guaranteed to finish in finite time, unlike a busy loop that polls a flag. This patch is a preparation for the bugfix in the next patch, where the same synchronize_net() call will also be used to sync with the TX datapath. Signed-off-by: Maxim Mikityanskiy Reviewed-by: Tariq Toukan Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net/tls: Protect from calling tls_dev_del for TLS RX twice

2020-11-26T01:31:06+00:00

tls_device_offload_cleanup_rx doesn't clear tls_ctx->netdev after calling tls_dev_del if TLX TX offload is also enabled. Clearing tls_ctx->netdev gets postponed until tls_device_gc_task. It leaves a time frame when tls_device_down may get called and call tls_dev_del for RX one extra time, confusing the driver, which may lead to a crash. This patch corrects this racy behavior by adding a flag to prevent tls_device_down from calling tls_dev_del the second time. Fixes: e8f69799810c ("net/tls: Add generic NIC offload infrastructure") Signed-off-by: Maxim Mikityanskiy Signed-off-by: Saeed Mahameed Link: https://lore.kernel.org/r/20201125221810.69870-1-saeedm@nvidia.com Signed-off-by: Jakub Kicinski

net/tls: Fix wrong record sn in async mode of device resync

2020-11-17T22:41:20+00:00

In async_resync mode, we log the TCP seq of records until the async request is completed. Later, in case one of the logged seqs matches the resync request, we return it, together with its record serial number. Before this fix, we mistakenly returned the serial number of the current record instead. Fixes: ed9b7646b06a ("net/tls: Add asynchronous resync") Signed-off-by: Tariq Toukan Reviewed-by: Boris Pismenny Link: https://lore.kernel.org/r/20201115131448.2702-1-tariqt@nvidia.com Signed-off-by: Jakub Kicinski

net/tls: remove a duplicate function prototype

2020-10-09T23:49:57+00:00

Remove one of the two instances of the function prototype for tls_validate_xmit_skb(). Signed-off-by: Randy Dunlap Cc: Boris Pismenny Cc: Aviad Yehezkel Cc: John Fastabend Cc: Daniel Borkmann Signed-off-by: Jakub Kicinski

net/tls: fix sign extension issue when left shifting u16 value

2020-06-30T20:36:56+00:00

Left shifting the u16 value promotes it to a int and then it gets sign extended to a u64. If len << 16 is greater than 0x7fffffff then the upper bits get set to 1 because of the implicit sign extension. Fix this by casting len to u64 before shifting it. Addresses-Coverity: ("integer handling issues") Fixes: ed9b7646b06a ("net/tls: Add asynchronous resync") Signed-off-by: Colin Ian King Reviewed-by: Tariq Toukan Signed-off-by: David S. Miller

net/tls: Add asynchronous resync

2020-06-27T21:00:22+00:00

This patch adds support for asynchronous resynchronization in tls_device. Async resync follows two distinct stages: 1. The NIC driver indicates that it would like to resync on some TLS record within the received packet (P), but the driver does not know (yet) which of the TLS records within the packet. At this stage, the NIC driver will query the device to find the exact TCP sequence for resync (tcpsn), however, the driver does not wait for the device to provide the response. 2. Eventually, the device responds, and the driver provides the tcpsn within the resync packet to KTLS. Now, KTLS can check the tcpsn against any processed TLS records within packet P, and also against any record that is processed in the future within packet P. The asynchronous resync path simplifies the device driver, as it can save bits on the packet completion (32-bit TCP sequence), and pass this information on an asynchronous command instead. Signed-off-by: Boris Pismenny Signed-off-by: Tariq Toukan Signed-off-by: Saeed Mahameed

Revert "net/tls: Add force_resync for driver resync"

2020-06-27T21:00:21+00:00

This reverts commit b3ae2459f89773adcbf16fef4b68deaaa3be1929. Revert the force resync API. Not in use. To be replaced by a better async resync API downstream. Signed-off-by: Boris Pismenny Signed-off-by: Tariq Toukan Reviewed-by: Maxim Mikityanskiy Signed-off-by: Saeed Mahameed

bpf: Fix running sk_skb program types with ktls

2020-06-01T21:48:32+00:00

KTLS uses a stream parser to collect TLS messages and send them to the upper layer tls receive handler. This ensures the tls receiver has a full TLS header to parse when it is run. However, when a socket has BPF_SK_SKB_STREAM_VERDICT program attached before KTLS is enabled we end up with two stream parsers running on the same socket. The result is both try to run on the same socket. First the KTLS stream parser runs and calls read_sock() which will tcp_read_sock which in turn calls tcp_rcv_skb(). This dequeues the skb from the sk_receive_queue. When this is done KTLS code then data_ready() callback which because we stacked KTLS on top of the bpf stream verdict program has been replaced with sk_psock_start_strp(). This will in turn kick the stream parser again and eventually do the same thing KTLS did above calling into tcp_rcv_skb() and dequeuing a skb from the sk_receive_queue. At this point the data stream is broke. Part of the stream was handled by the KTLS side some other bytes may have been handled by the BPF side. Generally this results in either missing data or more likely a "Bad Message" complaint from the kTLS receive handler as the BPF program steals some bytes meant to be in a TLS header and/or the TLS header length is no longer correct. We've already broke the idealized model where we can stack ULPs in any order with generic callbacks on the TX side to handle this. So in this patch we do the same thing but for RX side. We add a sk_psock_strp_enabled() helper so TLS can learn a BPF verdict program is running and add a tls_sw_has_ctx_rx() helper so BPF side can learn there is a TLS ULP on the socket. Then on BPF side we omit calling our stream parser to avoid breaking the data stream for the KTLS receiver. Then on the KTLS side we call BPF_SK_SKB_STREAM_VERDICT once the KTLS receiver is done with the packet but before it posts the msg to userspace. This gives us symmetry between the TX and RX halfs and IMO makes it usable again. On the TX side we process packets in this order BPF -> TLS -> TCP and on the receive side in the reverse order TCP -> TLS -> BPF. Discovered while testing OpenSSL 3.0 Alpha2.0 release. Fixes: d829e9c4112b5 ("tls: convert to generic sk_msg interface") Signed-off-by: John Fastabend Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/159079361946.5745.605854335665044485.stgit@john-Precision-5820-Tower Signed-off-by: Alexei Starovoitov