From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZrY+r0FysLGRAz7NWV4plCki9xJNIWO85wbcjVI5HqqxhkV8Z+yP0TITz5NMA1e9y0DcuSA ARC-Seal: i=1; a=rsa-sha256; t=1526631576; cv=none; d=google.com; s=arc-20160816; b=UTudPjDTxZlkQjmOgtErBhwPXfHa1RnL3/Mar5svhwjcvs1sHViVLFS4q3VtFoLjzZ GvT0Gz3EtVGCPqa8iCG10f98SMrD6reXzerE6rZK87H/gfTTfYcXsFMCuZk7sMWSPcc6 EuB2CAPf2bCkkZ0/vTbzI53GVABOvO6UcED/c/XvJpmL0Lx0/qCC/ZW7hJBGSxneJar/ i/0GRZGj9sOFO+cLVdsLsLT1vXvIp07dDUJRnhJnPjflEp9tEtpryY8rS0lDz6rhN7NU CPahT4npplzaoqAsl7aXHhVwM75g3ke0c2Ml2Eix9Zku9SmV7lHPwkubTycM3fmCC13Z nH8w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature:arc-authentication-results; bh=9HOPKo7o6dZk9Aye1oz387Fwi9O5y7FhtagT93n6xH4=; b=X+LbcG7nZLJyUsQDZkhMTzcClo3UrU/aVtxLtVs0DIWK39DBQcotCqTDUizzDMHh3y 2p3x+Q7/HP/N1W3u5NfSF/9oU5Sor8ntqxjdNiYpFonxNc1aihFRu1BoTyWwu9LHbw68 KPEdgw7IosrQoWzGiqpgGzkA6cm3E0RVOSD8OdiFvkVyrdomsWcKU60wRo4sG8wEGcQ2 K1Sh8zReCZfahWlkXvCbf3kdia4cP1+liuF00vGULvrPpMVJ8KPnWMD+yotQUkDvaWhM jCJypKaBcLvO5QVUCFGQGdlPLmk9p8+R5D4Gv81RKZVNzA8fka3feq9QhoCnH9BQwLtc LH/g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=ZXahYXN6; spf=pass (google.com: domain of srs0=xuy6=if=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=XuY6=IF=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=ZXahYXN6; spf=pass (google.com: domain of srs0=xuy6=if=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=XuY6=IF=linuxfoundation.org=gregkh@kernel.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andre Tomt , Dave Watson , "David S. Miller" Subject: [PATCH 4.14 16/45] net/tls: Dont recursively call push_record during tls_write_space callbacks Date: Fri, 18 May 2018 10:15:33 +0200 Message-Id: <20180518081531.155286878@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180518081530.331586165@linuxfoundation.org> References: <20180518081530.331586165@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1600789176003617426?= X-GMAIL-MSGID: =?utf-8?q?1600789231662293080?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dave Watson [ 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 --- include/net/tls.h | 1 + net/tls/tls_main.c | 7 +++++++ 2 files changed, 8 insertions(+) --- a/include/net/tls.h +++ b/include/net/tls.h @@ -98,6 +98,7 @@ struct tls_context { struct scatterlist *partially_sent_record; u16 partially_sent_offset; unsigned long flags; + bool in_tcp_sendpages; u16 pending_open_record_frags; int (*push_pending_record)(struct sock *sk, int flags); --- a/net/tls/tls_main.c +++ b/net/tls/tls_main.c @@ -87,6 +87,7 @@ int tls_push_sg(struct sock *sk, size = sg->length - offset; offset += sg->offset; + ctx->in_tcp_sendpages = true; while (1) { if (sg_is_last(sg)) sendpage_flags = flags; @@ -121,6 +122,8 @@ retry: } clear_bit(TLS_PENDING_CLOSED_RECORD, &ctx->flags); + ctx->in_tcp_sendpages = false; + ctx->sk_write_space(sk); return 0; } @@ -190,6 +193,10 @@ static void tls_write_space(struct sock { struct tls_context *ctx = tls_get_ctx(sk); + /* We are already sending pages, ignore notification */ + if (ctx->in_tcp_sendpages) + return; + if (!sk->sk_write_pending && tls_is_pending_closed_record(ctx)) { gfp_t sk_allocation = sk->sk_allocation; int rc;