From patchwork Thu Feb 4 19:07:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 1436263 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=aFBId6dL; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4DWpdv6s6wz9rx6 for ; Fri, 5 Feb 2021 06:34:27 +1100 (AEDT) Received: from localhost ([::1]:36362 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l7kOW-00042P-Pg for incoming@patchwork.ozlabs.org; Thu, 04 Feb 2021 14:34:24 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:47562) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l7jyM-0003TW-UQ for qemu-devel@nongnu.org; Thu, 04 Feb 2021 14:07:22 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:22933) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l7jyI-0001Cl-Mi for qemu-devel@nongnu.org; Thu, 04 Feb 2021 14:07:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612465637; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=hbBX3TWe854elgMN2WD58aLORgdEEqzv/UYsotiCu5U=; b=aFBId6dLht1agQbazk7JrtoAdPOTxaBYzmwovuaTFvf38H73i7tKt3LBMl9T2vcV/2vNvA b9K1B7iRTD+aFK1MookqAdGe/DLRJJhwotWIY5k3pCNGhJqjHx7odWkBaQV/IJk/CJpnn6 myjn0YXVE/i62iDZJsCCWukBCvjjPMI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-572-_3L6b6GIMTWLTFbD3d-SNA-1; Thu, 04 Feb 2021 14:07:15 -0500 X-MC-Unique: _3L6b6GIMTWLTFbD3d-SNA-1 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9D730106BAB8; Thu, 4 Feb 2021 19:07:14 +0000 (UTC) Received: from blue.redhat.com (ovpn-112-103.phx2.redhat.com [10.3.112.103]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3EA3D5D9CC; Thu, 4 Feb 2021 19:07:12 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Subject: [PATCH 1/3] utils: Improve qemu_strtosz() to have 64 bits of precision Date: Thu, 4 Feb 2021 13:07:06 -0600 Message-Id: <20210204190708.1306296-2-eblake@redhat.com> In-Reply-To: <20210204190708.1306296-1-eblake@redhat.com> References: <20210204190708.1306296-1-eblake@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=63.128.21.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.351, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , vsementsov@virtuozzo.com, berrange@redhat.com, qemu-block@nongnu.org, tao3.xu@intel.com, rjones@redhat.com, armbru@redhat.com, Max Reitz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" We have multiple clients of qemu_strtosz (qemu-io, the opts visitor, the keyval visitor), and it gets annoying that edge-case testing is impacted by implicit rounding to 53 bits of precision due to parsing with strtod(). As an example posted by Rich Jones: $ nbdkit memory $(( 2**63 - 2**30 )) --run \ 'build/qemu-io -f raw "$uri" -c "w -P 3 $(( 2**63 - 2**30 - 512 )) 512" ' write failed: Input/output error because 9223372035781033472 got rounded to 0x7fffffffc0000000 which is out of bounds. It is also worth noting that our existing parser, by virtue of using strtod(), accepts decimal AND hex numbers, even though test-cutils previously lacked any coverage of the latter. We do have existing clients that expect a hex parse to work (for example, iotest 33 using qemu-io -c "write -P 0xa 0x200 0x400"), but strtod() parses "08" as 8 rather than as an invalid octal number, so we know there are no clients that depend on octal. Our use of strtod() also means that "0x1.8k" would actually parse as 1536 (the fraction is 8/16), rather than 1843 (if the fraction were 8/10); but as this was not covered in the testsuite, I have no qualms forbidding hex fractions as invalid, so this patch declares that the use of fractions is only supported with decimal input, and enhances the testsuite to document that. Our previous use of strtod() meant that -1 parsed as a negative; now that we parse with strtoull(), negative values can wrap around module 2^64, so we have to explicitly check whether the user passed in a '-'. We also had no testsuite coverage of "1.1e0k", which happened to parse under strtod() but is unlikely to occur in practice; as long as we are making things more robust, it is easy enough to reject the use of exponents in a strtod parse. The fix is done by breaking the parse into an integer prefix (no loss in precision), rejecting negative values (since we can no longer rely on strtod() to do that), determining if a decimal or hexadecimal parse was intended (with the new restriction that a fractional hex parse is not allowed), and where appropriate, using a floating point fractional parse (where we also scan to reject use of exponents in the fraction). The bulk of the patch is then updates to the testsuite to match our new precision, as well as adding new cases we reject (whether they were rejected or inadvertenly accepted before). Signed-off-by: Eric Blake --- Note that this approach differs from what has been attempted in the past; see the thread starting at https://lists.gnu.org/archive/html/qemu-devel/2019-12/msg00852.html That approach tried to parse both as strtoull and strtod and take whichever was longer, but that was harder to document. --- tests/test-cutils.c | 79 ++++++++++++++++++++++++++++++-------- tests/test-keyval.c | 24 +++++++++--- tests/test-qemu-opts.c | 20 +++++++--- util/cutils.c | 77 +++++++++++++++++++++++++++---------- tests/qemu-iotests/049.out | 7 +++- 5 files changed, 156 insertions(+), 51 deletions(-) diff --git a/tests/test-cutils.c b/tests/test-cutils.c index 1aa8351520ae..0c2c89d6f113 100644 --- a/tests/test-cutils.c +++ b/tests/test-cutils.c @@ -1960,6 +1960,13 @@ static void test_qemu_strtosz_simple(void) g_assert_cmpint(res, ==, 0); g_assert(endptr == str + 1); + /* Leading 0 gives decimal results, not octal */ + str = "08"; + err = qemu_strtosz(str, &endptr, &res); + g_assert_cmpint(err, ==, 0); + g_assert_cmpint(res, ==, 8); + g_assert(endptr == str + 2); + str = "12345"; err = qemu_strtosz(str, &endptr, &res); g_assert_cmpint(err, ==, 0); @@ -1970,7 +1977,7 @@ static void test_qemu_strtosz_simple(void) g_assert_cmpint(err, ==, 0); g_assert_cmpint(res, ==, 12345); - /* Note: precision is 53 bits since we're parsing with strtod() */ + /* Note: If there is no '.', we get full 64 bits of precision */ str = "9007199254740991"; /* 2^53-1 */ err = qemu_strtosz(str, &endptr, &res); @@ -1987,7 +1994,7 @@ static void test_qemu_strtosz_simple(void) str = "9007199254740993"; /* 2^53+1 */ err = qemu_strtosz(str, &endptr, &res); g_assert_cmpint(err, ==, 0); - g_assert_cmpint(res, ==, 0x20000000000000); /* rounded to 53 bits */ + g_assert_cmpint(res, ==, 0x20000000000001); g_assert(endptr == str + 16); str = "18446744073709549568"; /* 0xfffffffffffff800 (53 msbs set) */ @@ -1999,11 +2006,35 @@ static void test_qemu_strtosz_simple(void) str = "18446744073709550591"; /* 0xfffffffffffffbff */ err = qemu_strtosz(str, &endptr, &res); g_assert_cmpint(err, ==, 0); - g_assert_cmpint(res, ==, 0xfffffffffffff800); /* rounded to 53 bits */ + g_assert_cmpint(res, ==, 0xfffffffffffffbff); g_assert(endptr == str + 20); - /* 0x7ffffffffffffe00..0x7fffffffffffffff get rounded to - * 0x8000000000000000, thus -ERANGE; see test_qemu_strtosz_erange() */ + str = "18446744073709551615"; /* 0xffffffffffffffff */ + err = qemu_strtosz(str, &endptr, &res); + g_assert_cmpint(err, ==, 0); + g_assert_cmpint(res, ==, 0xffffffffffffffff); + g_assert(endptr == str + 20); + +} + +static void test_qemu_strtosz_hex(void) +{ + const char *str; + const char *endptr; + int err; + uint64_t res = 0xbaadf00d; + + str = "0x0"; + err = qemu_strtosz(str, &endptr, &res); + g_assert_cmpint(err, ==, 0); + g_assert_cmpint(res, ==, 0); + g_assert(endptr == str + 3); + + str = "0xa"; + err = qemu_strtosz(str, &endptr, &res); + g_assert_cmpint(err, ==, 0); + g_assert_cmpint(res, ==, 10); + g_assert(endptr == str + 3); } static void test_qemu_strtosz_units(void) @@ -2106,6 +2137,21 @@ static void test_qemu_strtosz_invalid(void) err = qemu_strtosz(str, &endptr, &res); g_assert_cmpint(err, ==, -EINVAL); g_assert(endptr == str); + + str = "1.1e5"; + err = qemu_strtosz(str, &endptr, &res); + g_assert_cmpint(err, ==, -EINVAL); + g_assert(endptr == str); + + str = "1.1B"; + err = qemu_strtosz(str, &endptr, &res); + g_assert_cmpint(err, ==, -EINVAL); + g_assert(endptr == str); + + str = "0x1.8k"; + err = qemu_strtosz(str, &endptr, &res); + g_assert_cmpint(err, ==, -EINVAL); + g_assert(endptr == str); } static void test_qemu_strtosz_trailing(void) @@ -2145,17 +2191,7 @@ static void test_qemu_strtosz_erange(void) g_assert_cmpint(err, ==, -ERANGE); g_assert(endptr == str + 2); - str = "18446744073709550592"; /* 0xfffffffffffffc00 */ - err = qemu_strtosz(str, &endptr, &res); - g_assert_cmpint(err, ==, -ERANGE); - g_assert(endptr == str + 20); - - str = "18446744073709551615"; /* 2^64-1 */ - err = qemu_strtosz(str, &endptr, &res); - g_assert_cmpint(err, ==, -ERANGE); - g_assert(endptr == str + 20); - - str = "18446744073709551616"; /* 2^64 */ + str = "18446744073709551616"; /* 2^64; see strtosz_simple for 2^64-1 */ err = qemu_strtosz(str, &endptr, &res); g_assert_cmpint(err, ==, -ERANGE); g_assert(endptr == str + 20); @@ -2168,15 +2204,22 @@ static void test_qemu_strtosz_erange(void) static void test_qemu_strtosz_metric(void) { - const char *str = "12345k"; + const char *str; int err; const char *endptr; uint64_t res = 0xbaadf00d; + str = "12345k"; err = qemu_strtosz_metric(str, &endptr, &res); g_assert_cmpint(err, ==, 0); g_assert_cmpint(res, ==, 12345000); g_assert(endptr == str + 6); + + str = "12.345M"; + err = qemu_strtosz_metric(str, &endptr, &res); + g_assert_cmpint(err, ==, 0); + g_assert_cmpint(res, ==, 12345000); + g_assert(endptr == str + 7); } int main(int argc, char **argv) @@ -2443,6 +2486,8 @@ int main(int argc, char **argv) g_test_add_func("/cutils/strtosz/simple", test_qemu_strtosz_simple); + g_test_add_func("/cutils/strtosz/hex", + test_qemu_strtosz_hex); g_test_add_func("/cutils/strtosz/units", test_qemu_strtosz_units); g_test_add_func("/cutils/strtosz/float", diff --git a/tests/test-keyval.c b/tests/test-keyval.c index ee927fe4e427..13be763650b2 100644 --- a/tests/test-keyval.c +++ b/tests/test-keyval.c @@ -445,9 +445,9 @@ static void test_keyval_visit_size(void) visit_end_struct(v, NULL); visit_free(v); - /* Note: precision is 53 bits since we're parsing with strtod() */ + /* Note: full 64 bits of precision */ - /* Around limit of precision: 2^53-1, 2^53, 2^53+1 */ + /* Around double limit of precision: 2^53-1, 2^53, 2^53+1 */ qdict = keyval_parse("sz1=9007199254740991," "sz2=9007199254740992," "sz3=9007199254740993", @@ -460,7 +460,7 @@ static void test_keyval_visit_size(void) visit_type_size(v, "sz2", &sz, &error_abort); g_assert_cmphex(sz, ==, 0x20000000000000); visit_type_size(v, "sz3", &sz, &error_abort); - g_assert_cmphex(sz, ==, 0x20000000000000); + g_assert_cmphex(sz, ==, 0x20000000000001); visit_check_struct(v, &error_abort); visit_end_struct(v, NULL); visit_free(v); @@ -475,7 +475,7 @@ static void test_keyval_visit_size(void) visit_type_size(v, "sz1", &sz, &error_abort); g_assert_cmphex(sz, ==, 0x7ffffffffffffc00); visit_type_size(v, "sz2", &sz, &error_abort); - g_assert_cmphex(sz, ==, 0x7ffffffffffffc00); + g_assert_cmphex(sz, ==, 0x7ffffffffffffdff); visit_check_struct(v, &error_abort); visit_end_struct(v, NULL); visit_free(v); @@ -490,14 +490,26 @@ static void test_keyval_visit_size(void) visit_type_size(v, "sz1", &sz, &error_abort); g_assert_cmphex(sz, ==, 0xfffffffffffff800); visit_type_size(v, "sz2", &sz, &error_abort); - g_assert_cmphex(sz, ==, 0xfffffffffffff800); + g_assert_cmphex(sz, ==, 0xfffffffffffffbff); + visit_check_struct(v, &error_abort); + visit_end_struct(v, NULL); + visit_free(v); + + /* Actual limit */ + qdict = keyval_parse("sz1=18446744073709551615", /* ffffffffffffffff */ + NULL, NULL, &error_abort); + v = qobject_input_visitor_new_keyval(QOBJECT(qdict)); + qobject_unref(qdict); + visit_start_struct(v, NULL, NULL, 0, &error_abort); + visit_type_size(v, "sz1", &sz, &error_abort); + g_assert_cmphex(sz, ==, 0xffffffffffffffff); visit_check_struct(v, &error_abort); visit_end_struct(v, NULL); visit_free(v); /* Beyond limits */ qdict = keyval_parse("sz1=-1," - "sz2=18446744073709550592", /* fffffffffffffc00 */ + "sz2=18446744073709551616", /* 2^64 */ NULL, NULL, &error_abort); v = qobject_input_visitor_new_keyval(QOBJECT(qdict)); qobject_unref(qdict); diff --git a/tests/test-qemu-opts.c b/tests/test-qemu-opts.c index 8bbb17b1c726..f79b698e6715 100644 --- a/tests/test-qemu-opts.c +++ b/tests/test-qemu-opts.c @@ -654,9 +654,9 @@ static void test_opts_parse_size(void) g_assert_cmpuint(opts_count(opts), ==, 1); g_assert_cmpuint(qemu_opt_get_size(opts, "size1", 1), ==, 0); - /* Note: precision is 53 bits since we're parsing with strtod() */ + /* Note: full 64 bits of precision */ - /* Around limit of precision: 2^53-1, 2^53, 2^54 */ + /* Around double limit of precision: 2^53-1, 2^53, 2^53+1 */ opts = qemu_opts_parse(&opts_list_02, "size1=9007199254740991," "size2=9007199254740992," @@ -668,7 +668,7 @@ static void test_opts_parse_size(void) g_assert_cmphex(qemu_opt_get_size(opts, "size2", 1), ==, 0x20000000000000); g_assert_cmphex(qemu_opt_get_size(opts, "size3", 1), - ==, 0x20000000000000); + ==, 0x20000000000001); /* Close to signed upper limit 0x7ffffffffffffc00 (53 msbs set) */ opts = qemu_opts_parse(&opts_list_02, @@ -679,7 +679,7 @@ static void test_opts_parse_size(void) g_assert_cmphex(qemu_opt_get_size(opts, "size1", 1), ==, 0x7ffffffffffffc00); g_assert_cmphex(qemu_opt_get_size(opts, "size2", 1), - ==, 0x7ffffffffffffc00); + ==, 0x7ffffffffffffdff); /* Close to actual upper limit 0xfffffffffffff800 (53 msbs set) */ opts = qemu_opts_parse(&opts_list_02, @@ -690,14 +690,22 @@ static void test_opts_parse_size(void) g_assert_cmphex(qemu_opt_get_size(opts, "size1", 1), ==, 0xfffffffffffff800); g_assert_cmphex(qemu_opt_get_size(opts, "size2", 1), - ==, 0xfffffffffffff800); + ==, 0xfffffffffffffbff); + + /* Actual limit */ + opts = qemu_opts_parse(&opts_list_02, + "size1=18446744073709551615", /* ffffffffffffffff */ + false, &error_abort); + g_assert_cmpuint(opts_count(opts), ==, 1); + g_assert_cmphex(qemu_opt_get_size(opts, "size1", 1), + ==, 0xffffffffffffffff); /* Beyond limits */ opts = qemu_opts_parse(&opts_list_02, "size1=-1", false, &err); error_free_or_abort(&err); g_assert(!opts); opts = qemu_opts_parse(&opts_list_02, - "size1=18446744073709550592", /* fffffffffffffc00 */ + "size1=18446744073709551616", /* 2^64 */ false, &err); error_free_or_abort(&err); g_assert(!opts); diff --git a/util/cutils.c b/util/cutils.c index 0b5073b33012..0234763bd70b 100644 --- a/util/cutils.c +++ b/util/cutils.c @@ -241,10 +241,21 @@ static int64_t suffix_mul(char suffix, int64_t unit) } /* - * Convert string to bytes, allowing either B/b for bytes, K/k for KB, - * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned - * in *end, if not NULL. Return -ERANGE on overflow, and -EINVAL on - * other error. + * Convert size string to bytes. + * + * Allow either B/b for bytes, K/k for KB, M/m for MB, G/g for GB or + * T/t for TB, with scaling based on @unit, and with @default_suffix + * implied if no explicit suffix was given. + * + * The end pointer will be returned in *end, if not NULL. If there is + * no fraction, the input can be decimal or hexadecimal; if there is a + * fraction, then the input must be decimal and there must be a suffix + * (possibly by @default_suffix) larger than Byte, and the fractional + * portion may suffer from precision loss or rounding. The input must + * be positive. + * + * Return -ERANGE on overflow (with *@end advanced), and -EINVAL on + * other error (with *@end left unchanged). */ static int do_strtosz(const char *nptr, const char **end, const char default_suffix, int64_t unit, @@ -253,40 +264,66 @@ static int do_strtosz(const char *nptr, const char **end, int retval; const char *endptr; unsigned char c; - int mul_required = 0; - double val, mul, integral, fraction; + bool mul_required = false; + uint64_t val; + int64_t mul; + double fraction = 0.0; - retval = qemu_strtod_finite(nptr, &endptr, &val); + /* Parse integral portion as decimal. */ + retval = qemu_strtou64(nptr, &endptr, 10, &val); if (retval) { goto out; } - fraction = modf(val, &integral); - if (fraction != 0) { - mul_required = 1; + if (strchr(nptr, '-') != NULL) { + retval = -ERANGE; + goto out; + } + if (val == 0 && (*endptr == 'x' || *endptr == 'X')) { + /* Input looks like hex, reparse, and insist on no fraction. */ + retval = qemu_strtou64(nptr, &endptr, 16, &val); + if (retval) { + goto out; + } + if (*endptr == '.') { + endptr = nptr; + retval = -EINVAL; + goto out; + } + } else if (*endptr == '.') { + /* Input is fractional, insist on 0 <= fraction < 1, with no exponent */ + retval = qemu_strtod_finite(endptr, &endptr, &fraction); + if (retval) { + endptr = nptr; + goto out; + } + if (fraction >= 1.0 || memchr(nptr, 'e', endptr - nptr) + || memchr(nptr, 'E', endptr - nptr)) { + endptr = nptr; + retval = -EINVAL; + goto out; + } + if (fraction != 0) { + mul_required = true; + } } c = *endptr; mul = suffix_mul(c, unit); - if (mul >= 0) { + if (mul > 0) { endptr++; } else { mul = suffix_mul(default_suffix, unit); - assert(mul >= 0); + assert(mul > 0); } if (mul == 1 && mul_required) { + endptr = nptr; retval = -EINVAL; goto out; } - /* - * Values near UINT64_MAX overflow to 2**64 when converting to double - * precision. Compare against the maximum representable double precision - * value below 2**64, computed as "the next value after 2**64 (0x1p64) in - * the direction of 0". - */ - if ((val * mul > nextafter(0x1p64, 0)) || val < 0) { + if (val > UINT64_MAX / mul) { retval = -ERANGE; goto out; } - *result = val * mul; + *result = val * mul + (uint64_t) (fraction * mul); retval = 0; out: diff --git a/tests/qemu-iotests/049.out b/tests/qemu-iotests/049.out index b1d8fd9107ef..f38d3ccd5978 100644 --- a/tests/qemu-iotests/049.out +++ b/tests/qemu-iotests/049.out @@ -98,10 +98,13 @@ qemu-img create -f qcow2 -o size=-1024 TEST_DIR/t.qcow2 qemu-img: TEST_DIR/t.qcow2: Value '-1024' is out of range for parameter 'size' qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- -1k -qemu-img: Invalid image size specified. Must be between 0 and 9223372036854775807. +qemu-img: Invalid image size specified. You may use k, M, G, T, P or E suffixes for +qemu-img: kilobytes, megabytes, gigabytes, terabytes, petabytes and exabytes. qemu-img create -f qcow2 -o size=-1k TEST_DIR/t.qcow2 -qemu-img: TEST_DIR/t.qcow2: Value '-1k' is out of range for parameter 'size' +qemu-img: TEST_DIR/t.qcow2: Parameter 'size' expects a non-negative number below 2^64 +Optional suffix k, M, G, T, P or E means kilo-, mega-, giga-, tera-, peta- +and exabytes, respectively. qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- 1kilobyte qemu-img: Invalid image size specified. You may use k, M, G, T, P or E suffixes for