Fix format-truncation compile failure by typecasting USB IDs (#8250)

This patch adds safe_atoux16 for parsing an unsigned hexadecimal 16bit int, and
uses that for parsing USB device and vendor IDs.

This fixes a compile error with gcc-8 because while we know that USB IDs are 2 bytes,
the compiler does not know that.

../src/udev/udev-builtin-hwdb.c:80:38: error: '%04X' directive output may be
truncated writing between 4 and 8 bytes into a region of size between 2 and 6
[-Werror=format-truncation=]

Signed-off-by: Adam Williamson <awilliam@redhat.com>
Signed-off-by: Patrick Uiterwijk <puiterwijk@redhat.com>

diff --git a/src/basic/parse-util.c b/src/basic/parse-util.c
index 54d1081a0470a5747ae49f3d07d769a6cf636737..c8bca5a3087781c84dbef5373432948ff19698ee 100644 (file)
--- a/src/basic/parse-util.c
+++ b/src/basic/parse-util.c
@@ -536,6 +536,30 @@ int safe_atoi16(const char *s, int16_t *ret) {
         return 0;
 }
 
+int safe_atoux16(const char *s, uint16_t *ret) {
+        char *x = NULL;
+        unsigned long l;
+
+        assert(s);
+        assert(ret);
+
+        s += strspn(s, WHITESPACE);
+
+        errno = 0;
+        l = strtoul(s, &x, 16);
+        if (errno > 0)
+                return -errno;
+        if (!x || x == s || *x != 0)
+                return -EINVAL;
+        if (s[0] == '-')
+                return -ERANGE;
+        if ((unsigned long) (uint16_t) l != l)
+                return -ERANGE;
+
+        *ret = (uint16_t) l;
+        return 0;
+}
+
 int safe_atod(const char *s, double *ret_d) {
         _cleanup_(freelocalep) locale_t loc = (locale_t) 0;
         char *x = NULL;

diff --git a/src/basic/parse-util.h b/src/basic/parse-util.h
index f35a61121ab0e203c1c82e714c03492430b31dd0..50d3804621c7596bf6227b43f9fc148b44b43781 100644 (file)
--- a/src/basic/parse-util.h
+++ b/src/basic/parse-util.h
@@ -56,6 +56,8 @@ int safe_atou8(const char *s, uint8_t *ret);
 int safe_atou16(const char *s, uint16_t *ret);
 int safe_atoi16(const char *s, int16_t *ret);
 
+int safe_atoux16(const char *s, uint16_t *ret);
+
 static inline int safe_atou32(const char *s, uint32_t *ret_u) {
         assert_cc(sizeof(uint32_t) == sizeof(unsigned));
         return safe_atou(s, (unsigned*) ret_u);

diff --git a/src/test/test-parse-util.c b/src/test/test-parse-util.c
index 668b5cdee67f7adfd44b751b00ea6966baa3d825..10348123f6b4fbe1fa5fcd7854a271968d4af1cb 100644 (file)
--- a/src/test/test-parse-util.c
+++ b/src/test/test-parse-util.c
@@ -470,6 +470,44 @@ static void test_safe_atoi16(void) {
         assert_se(r == -EINVAL);
 }
 
+static void test_safe_atoux16(void) {
+        int r;
+        uint16_t l;
+
+        r = safe_atoux16("1234", &l);
+        assert_se(r == 0);
+        assert_se(l == 0x1234);
+
+        r = safe_atoux16("abcd", &l);
+        assert_se(r == 0);
+        assert_se(l == 0xabcd);
+
+        r = safe_atoux16("  1234", &l);
+        assert_se(r == 0);
+        assert_se(l == 0x1234);
+
+        r = safe_atoux16("12345", &l);
+        assert_se(r == -ERANGE);
+
+        r = safe_atoux16("-1", &l);
+        assert_se(r == -ERANGE);
+
+        r = safe_atoux16("  -1", &l);
+        assert_se(r == -ERANGE);
+
+        r = safe_atoux16("junk", &l);
+        assert_se(r == -EINVAL);
+
+        r = safe_atoux16("123x", &l);
+        assert_se(r == -EINVAL);
+
+        r = safe_atoux16("12.3", &l);
+        assert_se(r == -EINVAL);
+
+        r = safe_atoux16("", &l);
+        assert_se(r == -EINVAL);
+}
+
 static void test_safe_atou64(void) {
         int r;
         uint64_t l;
@@ -754,6 +792,7 @@ int main(int argc, char *argv[]) {
         test_safe_atolli();
         test_safe_atou16();
         test_safe_atoi16();
+        test_safe_atoux16();
         test_safe_atou64();
         test_safe_atoi64();
         test_safe_atod();