From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com ([209.132.183.28]:52598 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726149AbfBPHZq (ORCPT ); Sat, 16 Feb 2019 02:25:46 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0D3D85944F for ; Sat, 16 Feb 2019 07:25:46 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-12-20.pek2.redhat.com [10.72.12.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id 28B105D9C6 for ; Sat, 16 Feb 2019 07:25:44 +0000 (UTC) From: Zorro Lang Subject: [PATCH v2] fsstress: avoid infinite zero byte reading Date: Sat, 16 Feb 2019 15:25:40 +0800 Message-Id: <20190216072540.26272-1-zlang@redhat.com> Sender: fstests-owner@vger.kernel.org To: fstests@vger.kernel.org List-ID: copyrange_f and splice_f functions use a while loop to read a file, it's fine if there's only one fsstress process(and its children), but if some third part testing processes remove the file in the middle phase of copyrange_f running, copyrange_f maybe always return 0, and the while loop can't be end. As below: root 47184 xxxxxx S+ ./fsstress -R -d /mnt/scratch -n 10000 -p 20 -v root 47187 xxxxxx R+ ./fsstress -d /mnt/scratch -n 10000 -p 20 -v root 47199 xxxxxx R+ ./fsstress -d /mnt/scratch -n 10000 -p 20 -v root 47314 xxxxxx S+ grep --color=auto fsstress ... ... copy_file_range(3, [372258], 4, [2658770], 71179, 0) = 0 copy_file_range(3, [372258], 4, [2658770], 71179, 0) = 0 copy_file_range(3, [372258], 4, [2658770], 71179, 0) = 0 copy_file_range(3, [372258], 4, [2658770], 71179, 0) = 0 ... ... lr-x------. 1 root root 64 Jan 28 11:34 /proc/47187/fd/3 -> '/mnt/scratch/p2/f2 (deleted)' Signed-off-by: Zorro Lang --- V2 remove 300 times loop, just return if get ret == 0 Thanks, Zorro ltp/fsstress.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/ltp/fsstress.c b/ltp/fsstress.c index 25e0c3e2..138f7ecf 100644 --- a/ltp/fsstress.c +++ b/ltp/fsstress.c @@ -2363,7 +2363,7 @@ copyrange_f( int v2; int fd1; int fd2; - size_t ret; + size_t ret = 0; int e; /* Load paths */ @@ -2452,7 +2452,7 @@ copyrange_f( if (ret < 0) { if (errno != EAGAIN || tries++ >= 300) break; - } else if (ret > len) + } else if (ret > len || ret == 0) break; else if (ret > 0) len -= ret; @@ -2908,6 +2908,9 @@ splice_f(int opno, long r) len -= ret1; total += ret1; + if (ret1 == 0) { + break; + } } if (ret1 < 0 || ret2 < 0) -- 2.17.2