From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-133.freemail.mail.aliyun.com ([115.124.30.133]:60570 "EHLO out30-133.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731070AbfHWHYP (ORCPT ); Fri, 23 Aug 2019 03:24:15 -0400 From: Eryu Guan Subject: [PATCH] ltp/fsx: avoid infinite loop while finding offset2 in clone/dedupe/copy range ops Date: Fri, 23 Aug 2019 15:22:59 +0800 Message-Id: <20190823072259.56671-1-eguan@linux.alibaba.com> Sender: fstests-owner@vger.kernel.org To: fstests@vger.kernel.org Cc: "Darrick J. Wong" , Eryu Guan List-ID: In CLONE/DEDUPE/COPY RANGE operations, we pick a "offset" and "size" first, then find a suitable "offset2" by looping if there's overlap (|offset2-offset| < size) or final file size is greater than max file size (offset2 + size > maxfilelen). But it's possible that there's no such suitable offset2 and we loop forever. e.g. block_size = 4096, offset = 0, size = 4096 and maxfilelen is a value smaller than 8212 (which could be set via '-l' option). Fix it by making sure maxfilelen/file_size is big enough to hold 'size' bytes from 'offset2', and just skip this operation if not. Signed-off-by: Eryu Guan --- ltp/fsx.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/ltp/fsx.c b/ltp/fsx.c index 06d08e4e93f3..f6eb3308e8bc 100644 --- a/ltp/fsx.c +++ b/ltp/fsx.c @@ -1825,6 +1825,14 @@ do { \ TRIM_LEN(off, len, size); \ } while (0) +#define CHECK_RANGE(off, len, size) \ +do { \ + if ((off + len * 2) > size) { \ + log5(op, offset, size, -1, FL_SKIPPED); \ + goto out; \ + } \ +} while (0) + void cleanup(int sig) { @@ -1989,6 +1997,7 @@ test(void) TRIM_OFF_LEN(offset, size, file_size); offset = offset & ~(block_size - 1); size = size & ~(block_size - 1); + CHECK_RANGE(offset, size, maxfilelen); do { offset2 = random(); TRIM_OFF(offset2, maxfilelen); @@ -2003,6 +2012,7 @@ test(void) TRIM_OFF_LEN(offset, size, file_size); offset = offset & ~(block_size - 1); size = size & ~(block_size - 1); + CHECK_RANGE(offset, size, file_size); do { if (tries++ >= 30) { size = 0; @@ -2020,6 +2030,7 @@ test(void) offset -= offset % readbdy; if (o_direct) size -= size % readbdy; + CHECK_RANGE(offset, size, maxfilelen); do { offset2 = random(); TRIM_OFF(offset2, maxfilelen); -- 2.14.4.44.g2045bb6