@@ -24,6 +24,7 @@ int cmd_fmt_merge_msg(int argc,
.type = OPTION_INTEGER,
.long_name = "log",
.value = &shortlog_len,
+ .precision = sizeof(shortlog_len),
.argh = N_("n"),
.help = N_("populate log with at most <n> entries from shortlog"),
.flags = PARSE_OPT_OPTARG,
@@ -33,6 +34,7 @@ int cmd_fmt_merge_msg(int argc,
.type = OPTION_INTEGER,
.long_name = "summary",
.value = &shortlog_len,
+ .precision = sizeof(shortlog_len),
.argh = N_("n"),
.help = N_("alias for --log (deprecated)"),
.flags = PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN,
@@ -254,6 +254,7 @@ static struct option builtin_merge_options[] = {
.type = OPTION_INTEGER,
.long_name = "log",
.value = &shortlog_len,
+ .precision = sizeof(shortlog_len),
.argh = N_("n"),
.help = N_("add (at most <n>) entries from shortlog to merge commit message"),
.flags = PARSE_OPT_OPTARG,
@@ -671,6 +671,7 @@ int cmd_show_branch(int ac,
.type = OPTION_INTEGER,
.long_name = "more",
.value = &extra,
+ .precision = sizeof(extra),
.argh = N_("n"),
.help = N_("show <n> more commits after the common ancestor"),
.flags = PARSE_OPT_OPTARG,
@@ -483,6 +483,7 @@ int cmd_tag(int argc,
.type = OPTION_INTEGER,
.short_name = 'n',
.value = &filter.lines,
+ .precision = sizeof(filter.lines),
.argh = N_("n"),
.help = N_("print <n> lines of each tag message"),
.flags = PARSE_OPT_OPTARG,
@@ -172,33 +172,56 @@ static enum parse_opt_result do_get_value(struct parse_opt_ctx_t *p,
return (*opt->ll_callback)(p, opt, p_arg, p_unset);
}
case OPTION_INTEGER:
+ {
+ intmax_t upper_bound = INTMAX_MAX >> (bitsizeof(intmax_t) - CHAR_BIT * opt->precision);
+ intmax_t lower_bound = -upper_bound - 1;
+ intmax_t value;
+
if (unset) {
- *(int *)opt->value = 0;
- return 0;
- }
- if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
- *(int *)opt->value = opt->defval;
- return 0;
- }
- if (get_arg(p, opt, flags, &arg))
+ value = 0;
+ } else if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
+ value = opt->defval;
+ } else if (get_arg(p, opt, flags, &arg)) {
return -1;
- if (!*arg)
+ } else if (!*arg) {
return error(_("%s expects a numerical value"),
optname(opt, flags));
+ } else {
+ errno = 0;
+ value = strtoimax(arg, (char **)&s, 10);
+ if (*s)
+ return error(_("%s expects a numerical value"),
+ optname(opt, flags));
+ if (errno == ERANGE)
+ return error(_("value %s for %s not in range [%"PRIdMAX",%"PRIdMAX"]"),
+ arg, optname(opt, flags), lower_bound, upper_bound);
+ if (errno)
+ return error_errno(_("value %s for %s cannot be parsed"),
+ arg, optname(opt, flags));
+ }
- errno = 0;
- *(int *)opt->value = strtol(arg, (char **)&s, 10);
- if (*s)
- return error(_("%s expects a numerical value"),
- optname(opt, flags));
- if (errno == ERANGE)
+ if (value < lower_bound || value > upper_bound)
return error(_("value %s for %s not in range [%"PRIdMAX",%"PRIdMAX"]"),
- arg, optname(opt, flags), (intmax_t)LONG_MIN, (intmax_t)LONG_MAX);
- if (errno)
- return error_errno(_("value %s for %s cannot be parsed"),
- arg, optname(opt, flags));
+ arg, optname(opt, flags), lower_bound, upper_bound);
- return 0;
+ switch (opt->precision) {
+ case 1:
+ *(int8_t *)opt->value = value;
+ return 0;
+ case 2:
+ *(int16_t *)opt->value = value;
+ return 0;
+ case 4:
+ *(int32_t *)opt->value = value;
+ return 0;
+ case 8:
+ *(int64_t *)opt->value = value;
+ return 0;
+ default:
+ BUG("invalid precision for option %s",
+ optname(opt, flags));
+ }
+ }
case OPTION_MAGNITUDE:
if (unset) {
*(unsigned long *)opt->value = 0;
@@ -92,6 +92,10 @@ typedef int parse_opt_subcommand_fn(int argc, const char **argv,
* `value`::
* stores pointers to the values to be filled.
*
+ * `precision`::
+ * precision of the integer pointed to by `value` in number of bytes. Should
+ * typically be its `sizeof()`.
+ *
* `argh`::
* token to explain the kind of argument this option wants. Does not
* begin in capital letter, and does not end with a full stop.
@@ -151,6 +155,7 @@ struct option {
int short_name;
const char *long_name;
void *value;
+ size_t precision;
const char *argh;
const char *help;
@@ -214,6 +219,7 @@ struct option {
.short_name = (s), \
.long_name = (l), \
.value = (v), \
+ .precision = sizeof(*v), \
.argh = N_("n"), \
.help = (h), \
.flags = (f), \
@@ -120,6 +120,7 @@ int cmd__parse_options(int argc, const char **argv)
};
struct string_list expect = STRING_LIST_INIT_NODUP;
struct string_list list = STRING_LIST_INIT_NODUP;
+ int16_t i16 = 0;
struct option options[] = {
OPT_BOOL(0, "yes", &boolean, "get a boolean"),
@@ -139,6 +140,7 @@ int cmd__parse_options(int argc, const char **argv)
OPT_NEGBIT(0, "neg-or4", &boolean, "same as --no-or4", 4),
OPT_GROUP(""),
OPT_INTEGER('i', "integer", &integer, "get a integer"),
+ OPT_INTEGER(0, "i16", &i16, "get a 16 bit integer"),
OPT_INTEGER('j', NULL, &integer, "get a integer, too"),
OPT_MAGNITUDE('m', "magnitude", &magnitude, "get a magnitude"),
OPT_SET_INT(0, "set23", &integer, "set integer to 23", 23),
@@ -210,6 +212,7 @@ int cmd__parse_options(int argc, const char **argv)
}
show(&expect, &ret, "boolean: %d", boolean);
show(&expect, &ret, "integer: %d", integer);
+ show(&expect, &ret, "i16: %"PRIdMAX, (intmax_t) i16);
show(&expect, &ret, "magnitude: %lu", magnitude);
show(&expect, &ret, "timestamp: %"PRItime, timestamp);
show(&expect, &ret, "string: %s", string ? string : "(not set)");
@@ -22,6 +22,7 @@ usage: test-tool parse-options <options>
-i, --[no-]integer <n>
get a integer
+ --[no-]i16 <n> get a 16 bit integer
-j <n> get a integer, too
-m, --magnitude <n> get a magnitude
--[no-]set23 set integer to 23
@@ -136,6 +137,7 @@ test_expect_success 'OPT_MAGNITUDE() 3giga' '
cat >expect <<\EOF
boolean: 2
integer: 1729
+i16: 0
magnitude: 16384
timestamp: 0
string: 123
@@ -156,6 +158,7 @@ test_expect_success 'short options' '
cat >expect <<\EOF
boolean: 2
integer: 1729
+i16: 9000
magnitude: 16384
timestamp: 0
string: 321
@@ -167,7 +170,7 @@ file: prefix/fi.le
EOF
test_expect_success 'long options' '
- test-tool parse-options --boolean --integer 1729 --magnitude 16k \
+ test-tool parse-options --boolean --integer 1729 --i16 9000 --magnitude 16k \
--boolean --string2=321 --verbose --verbose --no-dry-run \
--abbrev=10 --file fi.le --obsolete \
>output 2>output.err &&
@@ -179,6 +182,7 @@ test_expect_success 'abbreviate to something longer than SHA1 length' '
cat >expect <<-EOF &&
boolean: 0
integer: 0
+ i16: 0
magnitude: 0
timestamp: 0
string: (not set)
@@ -253,6 +257,7 @@ test_expect_success 'superfluous value provided: cmdmode' '
cat >expect <<\EOF
boolean: 1
integer: 13
+i16: 0
magnitude: 0
timestamp: 0
string: 123
@@ -276,6 +281,7 @@ test_expect_success 'intermingled arguments' '
cat >expect <<\EOF
boolean: 0
integer: 2
+i16: 0
magnitude: 0
timestamp: 0
string: (not set)
@@ -343,6 +349,7 @@ cat >expect <<\EOF
Callback: "four", 0
boolean: 5
integer: 4
+i16: 0
magnitude: 0
timestamp: 0
string: (not set)
@@ -368,6 +375,7 @@ test_expect_success 'OPT_CALLBACK() and callback errors work' '
cat >expect <<\EOF
boolean: 1
integer: 23
+i16: 0
magnitude: 0
timestamp: 0
string: (not set)
@@ -447,6 +455,7 @@ test_expect_success 'OPT_NUMBER_CALLBACK() works' '
cat >expect <<\EOF
boolean: 0
integer: 0
+i16: 0
magnitude: 0
timestamp: 0
string: (not set)
@@ -789,4 +798,16 @@ test_expect_success 'overflowing integer' '
test_must_be_empty out
'
+test_expect_success 'i16 limits range' '
+ test-tool parse-options --i16 32767 >out &&
+ test_grep "i16: 32767" out &&
+ test_must_fail test-tool parse-options --i16 32768 2>err &&
+ test_grep "value 32768 for option .i16. not in range \[-32768,32767\]" err &&
+
+ test-tool parse-options --i16 -32768 >out &&
+ test_grep "i16: -32768" out &&
+ test_must_fail test-tool parse-options --i16 -32769 2>err &&
+ test_grep "value -32769 for option .i16. not in range \[-32768,32767\]" err
+'
+
test_done
The `OPTION_INTEGER` option type accepts a signed integer. The type of the underlying integer is a simple `int`, which restricts the range of values accepted by such options. But there is a catch: because the caller provides a pointer to the value via the `.value` field, which is a simple void pointer. This has two consequences: - There is no check whether the passed value is sufficiently long to store the entire range of `int`. This can lead to integer wraparound in the best case and out-of-bounds writes in the worst case. - Even when a caller knows that they want to store a value larger than `INT_MAX` they don't have a way to do so. Funny enough, even if the caller gets everything correct the parsing logic is still insufficient because we use `strtol()` to parse the argument, which returns a `long`. But as that value is implicitly cast when assigning it to the `int` field we may still get invalid results. In practice this doesn't tend to be a huge issue because users typically don't end up passing huge values to most commands. But the parsing logic is demonstrably broken, and it is too easy to get the calling convention wrong. Improve the situation by introducing a new `precision` field into the structure. This field gets assigned automatically by `OPT_INTEGER_F()` and tracks the size of the passed value. Like this it becomes possible for the caller to pass arbitrarily-sized integers and the underlying logic knows to handle it correctly by doing range checks. Furthermore, convert the code to use `strtoimax()` intstead of `strtol()` so that we can also parse values larger than `LONG_MAX`. Note that we do not yet assert signedness of the passed variable, which is another source of bugs. This will be handled in a subsequent commit. Signed-off-by: Patrick Steinhardt <ps@pks.im> --- builtin/fmt-merge-msg.c | 2 ++ builtin/merge.c | 1 + builtin/show-branch.c | 1 + builtin/tag.c | 1 + parse-options.c | 63 +++++++++++++++++++++++++++++-------------- parse-options.h | 6 +++++ t/helper/test-parse-options.c | 3 +++ t/t0040-parse-options.sh | 23 +++++++++++++++- 8 files changed, 79 insertions(+), 21 deletions(-)