From cf923b783efd565787e9ab006fb5608bb2a7297b Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Thu, 11 Feb 2021 14:44:36 -0600 Subject: utils: Improve qemu_strtosz() to have 64 bits of precision 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 until the previous patch. 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 modulo 2^64, so we have to explicitly check whether the user passed in a '-'; and make it consistent to also reject '-0'. This has the minor effect of treating negative values as EINVAL (with no change to endptr) rather than ERANGE (with endptr advanced to what was parsed), visible in the updated iotest output. 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 inadvertently accepted before). Signed-off-by: Eric Blake Message-Id: <20210211204438.1184395-3-eblake@redhat.com> Reviewed-by: Daniel P. Berrangé --- tests/qemu-iotests/049.out | 14 +++++--- tests/qemu-iotests/178.out.qcow2 | 3 +- tests/qemu-iotests/178.out.raw | 3 +- tests/test-cutils.c | 74 +++++++++++++++------------------------- tests/test-keyval.c | 35 +++++++++++++------ tests/test-qemu-opts.c | 33 ++++++++++++------ 6 files changed, 89 insertions(+), 73 deletions(-) (limited to 'tests') diff --git a/tests/qemu-iotests/049.out b/tests/qemu-iotests/049.out index b1d8fd9107..01f7b1f240 100644 --- a/tests/qemu-iotests/049.out +++ b/tests/qemu-iotests/049.out @@ -92,16 +92,22 @@ Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 cluster_size=65536 extended_l2=off comp == 3. Invalid sizes == qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- -1024 -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=-1024 TEST_DIR/t.qcow2 -qemu-img: TEST_DIR/t.qcow2: Value '-1024' 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 -- -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 diff --git a/tests/qemu-iotests/178.out.qcow2 b/tests/qemu-iotests/178.out.qcow2 index fe193fd5f4..0d51fe401e 100644 --- a/tests/qemu-iotests/178.out.qcow2 +++ b/tests/qemu-iotests/178.out.qcow2 @@ -13,7 +13,8 @@ qemu-img: Invalid option list: , qemu-img: Invalid parameter 'snapshot.foo' qemu-img: Failed in parsing snapshot param 'snapshot.foo=bar' qemu-img: --output must be used with human or json as argument. -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: Unknown file format 'foo' == Size calculation for a new file (human) == diff --git a/tests/qemu-iotests/178.out.raw b/tests/qemu-iotests/178.out.raw index 445e460fad..116241ddef 100644 --- a/tests/qemu-iotests/178.out.raw +++ b/tests/qemu-iotests/178.out.raw @@ -13,7 +13,8 @@ qemu-img: Invalid option list: , qemu-img: Invalid parameter 'snapshot.foo' qemu-img: Failed in parsing snapshot param 'snapshot.foo=bar' qemu-img: --output must be used with human or json as argument. -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: Unknown file format 'foo' == Size calculation for a new file (human) == diff --git a/tests/test-cutils.c b/tests/test-cutils.c index 6d9802e00b..bad3a60993 100644 --- a/tests/test-cutils.c +++ b/tests/test-cutils.c @@ -1978,8 +1978,6 @@ 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() */ - str = "9007199254740991"; /* 2^53-1 */ err = qemu_strtosz(str, &endptr, &res); g_assert_cmpint(err, ==, 0); @@ -1992,10 +1990,10 @@ static void test_qemu_strtosz_simple(void) g_assert_cmpint(res, ==, 0x20000000000000); g_assert(endptr == str + 16); - str = "9007199254740993"; /* 2^53+1 FIXME loss of precision is a bug */ + 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) */ @@ -2004,16 +2002,17 @@ static void test_qemu_strtosz_simple(void) g_assert_cmpint(res, ==, 0xfffffffffffff800); g_assert(endptr == str + 20); - str = "18446744073709550591"; /* 0xfffffffffffffbff FIXME */ + 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); - /* - * FIXME 0xfffffffffffffe00..0xffffffffffffffff get rounded to - * 2^64, 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) @@ -2166,45 +2165,43 @@ static void test_qemu_strtosz_invalid(void) g_assert(endptr == str); /* Fractional values require scale larger than bytes */ - /* FIXME endptr shouldn't move on -EINVAL */ str = "1.1B"; err = qemu_strtosz(str, &endptr, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert(endptr == str + 4); + g_assert(endptr == str); - /* FIXME endptr shouldn't move on -EINVAL */ str = "1.1"; err = qemu_strtosz(str, &endptr, &res); g_assert_cmpint(err, ==, -EINVAL); - g_assert(endptr == str + 3); + g_assert(endptr == str); - /* FIXME we should reject floating point exponents */ + /* No floating point exponents */ str = "1.5e1k"; err = qemu_strtosz(str, &endptr, &res); - g_assert_cmpint(err, ==, 0); - g_assert_cmpint(res, ==, 15360); - g_assert(endptr == str + 6); + g_assert_cmpint(err, ==, -EINVAL); + g_assert(endptr == str); - /* FIXME we should reject floating point exponents */ str = "1.5E+0k"; err = qemu_strtosz(str, &endptr, &res); - g_assert_cmpint(err, ==, 0); - g_assert_cmpint(res, ==, 1536); - g_assert(endptr == str + 7); + g_assert_cmpint(err, ==, -EINVAL); + g_assert(endptr == str); - /* FIXME we should reject hex fractions */ + /* No hex fractions */ str = "0x1.8k"; err = qemu_strtosz(str, &endptr, &res); - g_assert_cmpint(err, ==, 0); - g_assert_cmpint(res, ==, 1536); - g_assert(endptr == str + 6); + g_assert_cmpint(err, ==, -EINVAL); + g_assert(endptr == str); - /* FIXME we reject all other attempts at negative, why not -0 */ + /* No negative values */ str = "-0"; err = qemu_strtosz(str, &endptr, &res); - g_assert_cmpint(err, ==, 0); - g_assert_cmpint(res, ==, 0); - g_assert(endptr == str + 2); + g_assert_cmpint(err, ==, -EINVAL); + g_assert(endptr == str); + + str = "-1"; + err = qemu_strtosz(str, &endptr, &res); + g_assert_cmpint(err, ==, -EINVAL); + g_assert(endptr == str); } static void test_qemu_strtosz_trailing(void) @@ -2263,22 +2260,7 @@ static void test_qemu_strtosz_erange(void) int err; uint64_t res = 0xbaadf00d; - str = "-1"; - err = qemu_strtosz(str, &endptr, &res); - g_assert_cmpint(err, ==, -ERANGE); - g_assert(endptr == str + 2); - - str = "18446744073709550592"; /* 0xfffffffffffffc00 FIXME accept this */ - err = qemu_strtosz(str, &endptr, &res); - g_assert_cmpint(err, ==, -ERANGE); - g_assert(endptr == str + 20); - - str = "18446744073709551615"; /* 2^64-1 FIXME accept this */ - 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); diff --git a/tests/test-keyval.c b/tests/test-keyval.c index ee927fe4e4..e20c07cf3e 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", @@ -460,22 +460,25 @@ 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); - /* Close to signed upper limit 0x7ffffffffffffc00 (53 msbs set) */ - qdict = keyval_parse("sz1=9223372036854774784," /* 7ffffffffffffc00 */ - "sz2=9223372036854775295", /* 7ffffffffffffdff */ + /* Close to signed integer limit 2^63 */ + qdict = keyval_parse("sz1=9223372036854775807," /* 7fffffffffffffff */ + "sz2=9223372036854775808," /* 8000000000000000 */ + "sz3=9223372036854775809", /* 8000000000000001 */ 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, ==, 0x7ffffffffffffc00); + g_assert_cmphex(sz, ==, 0x7fffffffffffffff); visit_type_size(v, "sz2", &sz, &error_abort); - g_assert_cmphex(sz, ==, 0x7ffffffffffffc00); + g_assert_cmphex(sz, ==, 0x8000000000000000); + visit_type_size(v, "sz3", &sz, &error_abort); + g_assert_cmphex(sz, ==, 0x8000000000000001); visit_check_struct(v, &error_abort); visit_end_struct(v, NULL); visit_free(v); @@ -490,14 +493,26 @@ 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 2^64-1*/ + 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 8bbb17b1c7..6568e31a72 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," @@ -668,18 +668,21 @@ 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) */ + /* Close to signed int limit: 2^63-1, 2^63, 2^63+1 */ opts = qemu_opts_parse(&opts_list_02, - "size1=9223372036854774784," /* 7ffffffffffffc00 */ - "size2=9223372036854775295", /* 7ffffffffffffdff */ + "size1=9223372036854775807," /* 7fffffffffffffff */ + "size2=9223372036854775808," /* 8000000000000000 */ + "size3=9223372036854775809", /* 8000000000000001 */ false, &error_abort); - g_assert_cmpuint(opts_count(opts), ==, 2); + g_assert_cmpuint(opts_count(opts), ==, 3); g_assert_cmphex(qemu_opt_get_size(opts, "size1", 1), - ==, 0x7ffffffffffffc00); + ==, 0x7fffffffffffffff); g_assert_cmphex(qemu_opt_get_size(opts, "size2", 1), - ==, 0x7ffffffffffffc00); + ==, 0x8000000000000000); + g_assert_cmphex(qemu_opt_get_size(opts, "size3", 1), + ==, 0x8000000000000001); /* Close to actual upper limit 0xfffffffffffff800 (53 msbs set) */ opts = qemu_opts_parse(&opts_list_02, @@ -690,14 +693,22 @@ 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, 2^64-1 */ + 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); -- cgit v1.2.3-55-g7522