linux/net/strparser, branch v4.20

bpf, sockmap: convert to generic sk_msg interface

2018-10-15T19:23:19Z

Add a generic sk_msg layer, and convert current sockmap and later kTLS over to make use of it. While sk_buff handles network packet representation from netdevice up to socket, sk_msg handles data representation from application to socket layer. This means that sk_msg framework spans across ULP users in the kernel, and enables features such as introspection or filtering of data with the help of BPF programs that operate on this data structure. Latter becomes in particular useful for kTLS where data encryption is deferred into the kernel, and as such enabling the kernel to perform L7 introspection and policy based on BPF for TLS connections where the record is being encrypted after BPF has run and came to a verdict. In order to get there, first step is to transform open coding of scatter-gather list handling into a common core framework that subsystems can use. The code itself has been split and refactored into three bigger pieces: i) the generic sk_msg API which deals with managing the scatter gather ring, providing helpers for walking and mangling, transferring application data from user space into it, and preparing it for BPF pre/post-processing, ii) the plain sock map itself where sockets can be attached to or detached from; these bits are independent of i) which can now be used also without sock map, and iii) the integration with plain TCP as one protocol to be used for processing L7 application data (later this could e.g. also be extended to other protocols like UDP). The semantics are the same with the old sock map code and therefore no change of user facing behavior or APIs. While pursuing this work it also helped finding a number of bugs in the old sockmap code that we've fixed already in earlier commits. The test_sockmap kselftest suite passes through fine as well. Joint work with John. Signed-off-by: Daniel Borkmann Signed-off-by: John Fastabend Signed-off-by: Alexei Starovoitov

strparser: remove redundant variable 'rd_desc'

2018-08-01T17:00:06Z

Variable 'rd_desc' is being assigned but never used, so can be removed. fix this clang warning: net/strparser/strparser.c:411:20: warning: variable ‘rd_desc’ set but not used [-Wunused-but-set-variable] Signed-off-by: YueHaibing Signed-off-by: David S. Miller

Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net

2018-07-03T01:29:26Z

Simple overlapping changes in stmmac driver. Adjust skb_gro_flush_final_remcsum function signature to make GRO list changes in net-next, as per Stephen Rothwell's example merge resolution. Signed-off-by: David S. Miller

strparser: Call skb_unclone conditionally

2018-06-30T12:25:39Z

Calling skb_unclone() is expensive as it triggers a memcpy operation. Instead of calling skb_unclone() unconditionally, call it only when skb has a shared frag_list. This improves tls rx throughout significantly. Signed-off-by: Vakul Garg Suggested-by: Boris Pismenny Signed-off-by: David S. Miller

strparser: Remove early eaten to fix full tcp receive buffer stall

2018-06-28T12:37:26Z

On receving an incomplete message, the existing code stores the remaining length of the cloned skb in the early_eaten field instead of incrementing the value returned by __strp_recv. This defers invocation of sock_rfree for the current skb until the next invocation of __strp_recv, which returns early_eaten if early_eaten is non-zero. This behavior causes a stall when the current message occupies the very tail end of a massive skb, and strp_peek/need_bytes indicates that the remainder of the current message has yet to arrive on the socket. The TCP receive buffer is totally full, causing the TCP window to go to zero, so the remainder of the message will never arrive. Incrementing the value returned by __strp_recv by the amount otherwise stored in early_eaten prevents stalls of this nature. Signed-off-by: Doron Roberts-Kedes Signed-off-by: David S. Miller

strparser: Don't schedule in workqueue in paused state

2018-06-21T00:54:05Z

In function strp_data_ready(), it is useless to call queue_work if the state of strparser is already paused. The state checking should be done before calling queue_work. The change reduces the context switches and improves the ktls-rx throughput by approx 20% (measured on cortex-a53 based platform). Signed-off-by: Vakul Garg Acked-by: Dave Watson Signed-off-by: David S. Miller

strparser: Add __strp_unpause and use it in ktls.

2018-06-06T18:07:53Z

strp_unpause queues strp_work in order to parse any messages that arrived while the strparser was paused. However, the process invoking strp_unpause could eagerly parse a buffered message itself if it held the sock lock. __strp_unpause is an alternative to strp_pause that avoids the scheduling overhead that results when a receiving thread unpauses the strparser and waits for the next message to be delivered by the workqueue thread. This patch more than doubled the IOPS achieved in a benchmark of NBD traffic encrypted using ktls. Signed-off-by: Doron Roberts-Kedes Signed-off-by: David S. Miller

strparser: Do not call mod_delayed_work with a timeout of LONG_MAX

2018-04-23T01:09:16Z

struct sock's sk_rcvtimeo is initialized to LONG_MAX/MAX_SCHEDULE_TIMEOUT in sock_init_data. Calling mod_delayed_work with a timeout of LONG_MAX causes spurious execution of the work function. timer->expires is set equal to jiffies + LONG_MAX. When timer_base->clk falls behind the current value of jiffies, the delta between timer_base->clk and jiffies + LONG_MAX causes the expiration to be in the past. Returning early from strp_start_timer if timeo == LONG_MAX solves this problem. Found while testing net/tls_sw recv path. Fixes: 43a0c6751a322847 ("strparser: Stream parser for messages") Reviewed-by: Tejun Heo Signed-off-by: Doron Roberts-Kedes Signed-off-by: David S. Miller

strparser: Fix incorrect strp->need_bytes value.

2018-04-13T01:54:59Z

strp_data_ready resets strp->need_bytes to 0 if strp_peek_len indicates that the remainder of the message has been received. However, do_strp_work does not reset strp->need_bytes to 0. If do_strp_work completes a partial message, the value of strp->need_bytes will continue to reflect the needed bytes of the previous message, causing future invocations of strp_data_ready to return early if strp->need_bytes is less than strp_peek_len. Resetting strp->need_bytes to 0 in __strp_recv on handing a full message to the upper layer solves this problem. __strp_recv also calculates strp->need_bytes using stm->accum_len before stm->accum_len has been incremented by cand_len. This can cause strp->need_bytes to be equal to the full length of the message instead of the full length minus the accumulated length. This, in turn, causes strp_data_ready to return early, even when there is sufficient data to complete the partial message. Incrementing stm->accum_len before using it to calculate strp->need_bytes solves this problem. Found while testing net/tls_sw recv path. Fixes: 43a0c6751a322847 ("strparser: Stream parser for messages") Signed-off-by: Doron Roberts-Kedes Signed-off-by: David S. Miller

strparser: Fix sign of err codes

2018-03-27T15:00:18Z

strp_parser_err is called with a negative code everywhere, which then calls abort_parser with a negative code. strp_msg_timeout calls abort_parser directly with a positive code. Negate ETIMEDOUT to match signed-ness of other calls. The default abort_parser callback, strp_abort_strp, sets sk->sk_err to err. Also negate the error here so sk_err always holds a positive value, as the rest of the net code expects. Currently a negative sk_err can result in endless loops, or user code that thinks it actually sent/received err bytes. Found while testing net/tls_sw recv path. Fixes: 43a0c6751a322847 ("strparser: Stream parser for messages") Signed-off-by: Dave Watson Signed-off-by: David S. Miller