shaba/systemd
1
0
Fork 0
mirror of https://github.com/systemd/systemd.git synced 2024-11-02 10:51:20 +03:00
Code

Properly check for overflow in offsets

Browse Source
This commit is contained in:
Zbigniew Jędrzejewski-Szmek 2013-06-05 19:33:45 -04:00
parent 3001c74580
commit b32ff51219
2 changed files with 53 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
src/shared/util.c
View File

@ -2261,7 +2261,7 @@ ssize_t loop_write(int fd, const void *buf, size_t nbytes, bool do_poll) {
int parse_bytes(const char *t, off_t *bytes) {
static const struct {
const char *suffix;
off_t factor;
unsigned long long factor;
} table[] = {
{ "B", 1 },
{ "K", 1024ULL },
@ -2274,7 +2274,7 @@ int parse_bytes(const char *t, off_t *bytes) {
};
const char *p;
off_t r = 0;
unsigned long long r = 0;
assert(t);
assert(bytes);
@ -2301,7 +2301,17 @@ int parse_bytes(const char *t, off_t *bytes) {
for (i = 0; i < ELEMENTSOF(table); i++)
if (startswith(e, table[i].suffix)) {
r += (off_t) l * table[i].factor;
unsigned long long tmp;
if ((unsigned long long) l > ULLONG_MAX / table[i].factor)
return -ERANGE;
tmp = l * table[i].factor;
if (tmp > ULLONG_MAX - r)
return -ERANGE;
r += tmp;
if ((unsigned long long) (off_t) r != r)
return -ERANGE;
p = e + strlen(table[i].suffix);
break;
}
@ -2309,7 +2319,7 @@ int parse_bytes(const char *t, off_t *bytes) {
if (i >= ELEMENTSOF(table))
return -EINVAL;
} while (*p != 0);
} while (*p);
*bytes = r;

39
src/test/test-util.c
View File

@ -439,6 +439,44 @@ static void test_protect_errno(void) {
assert(errno == 12);
}
static void test_parse_bytes(void) {
off_t bytes;
assert_se(parse_bytes("111", &bytes) == 0);
assert_se(bytes == 111);
assert_se(parse_bytes(" 112 B", &bytes) == 0);
assert_se(bytes == 112);
assert_se(parse_bytes("3 K", &bytes) == 0);
assert_se(bytes == 3*1024);
assert_se(parse_bytes(" 4 M 11K", &bytes) == 0);
assert_se(bytes == 4*1024*1024 + 11 * 1024);
assert_se(parse_bytes("3B3G", &bytes) == 0);
assert_se(bytes == 3ULL*1024*1024*1024 + 3);
assert_se(parse_bytes("3B3G4T", &bytes) == 0);
assert_se(bytes == (4ULL*1024 + 3)*1024*1024*1024 + 3);
assert_se(parse_bytes("12P", &bytes) == 0);
assert_se(bytes == 12ULL * 1024*1024*1024*1024*1024);
assert_se(parse_bytes("3E 2P", &bytes) == 0);
assert_se(bytes == (3 * 1024 + 2ULL) * 1024*1024*1024*1024*1024);
assert_se(parse_bytes("12X", &bytes) == -EINVAL);
assert_se(parse_bytes("1024E", &bytes) == -ERANGE);
assert_se(parse_bytes("-1", &bytes) == -ERANGE);
assert_se(parse_bytes("-1024E", &bytes) == -ERANGE);
assert_se(parse_bytes("-1024P", &bytes) == -ERANGE);
assert_se(parse_bytes("-10B 20K", &bytes) == -ERANGE);
}
int main(int argc, char *argv[]) {
test_streq_ptr();
test_first_word();
@ -467,6 +505,7 @@ int main(int argc, char *argv[]) {
test_u64log2();
test_get_process_comm();
test_protect_errno();
test_parse_bytes();
return 0;
}