From: John Fastabend Date: Sat, 11 Jan 2020 06:12:05 +0000 (+0000) Subject: bpf: Sockmap/tls, skmsg can have wrapped skmsg that needs extra chaining X-Git-Tag: baikal/mips/sdk5.9~14532^2~18^2^2~1 X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=39f99840058f2fe07a0f1abe7edc6508bf7c4bc9;p=kernel.git bpf: Sockmap/tls, skmsg can have wrapped skmsg that needs extra chaining Its possible through a set of push, pop, apply helper calls to construct a skmsg, which is just a ring of scatterlist elements, with the start value larger than the end value. For example, end start |_0_|_1_| ... |_n_|_n+1_| Where end points at 1 and start points and n so that valid elements is the set {n, n+1, 0, 1}. Currently, because we don't build the correct chain only {n, n+1} will be sent. This adds a check and sg_chain call to correctly submit the above to the crypto and tls send path. Fixes: 635a8c9b3da8d ("tls: add bpf support to sk_msg handling") Signed-off-by: John Fastabend Signed-off-by: Daniel Borkmann Acked-by: Jonathan Lemon Cc: stable@vger.kernel.org Link: https://lore.kernel.org/bpf/20200111061206.8028-8-john.fastabend@gmail.com --- diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 31f6bbbc89923..21c7725d17ca8 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -729,6 +729,12 @@ static int tls_push_record(struct sock *sk, int flags, sg_mark_end(sk_msg_elem(msg_pl, i)); } + if (msg_pl->sg.end < msg_pl->sg.start) { + sg_chain(&msg_pl->sg.data[msg_pl->sg.start], + MAX_SKB_FRAGS - msg_pl->sg.start + 1, + msg_pl->sg.data); + } + i = msg_pl->sg.start; sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]);