diff options
authorRich Felker <>2014-09-05 02:50:38 -0400
committerRich Felker <>2014-09-05 02:50:38 -0400
commit80e6485455a9c75c029d0e976d2dd9c8e441dd72 (patch)
parent6e2bb7acf42589fb7130b039d0623e2ca42503dd (diff)
remove an extra layer of buffer copying in getnameinfo reverse dns
the outer getnameinfo function already has a properly-sized temporary buffer for storing the reverse dns (ptr) result. there is no reason for the callback to use a secondary buffer and copy it on success, and doing so potentially expanded the impact of the dn_expand bug that was fixed in commit 49d2c8c6bcf8c926e52c7f510033b6adc31355f5. this change reduces the code size by a small amount, and also reduces the run-time stack space requirements by about 256 bytes.
1 files changed, 2 insertions, 3 deletions
diff --git a/src/network/getnameinfo.c b/src/network/getnameinfo.c
index 588ed765..2ba66e33 100644
--- a/src/network/getnameinfo.c
+++ b/src/network/getnameinfo.c
@@ -113,11 +113,10 @@ static void reverse_services(char *buf, int port, int dgram)
static int dns_parse_callback(void *c, int rr, const void *data, int len, const void *packet)
- char tmp[256];
if (rr != RR_PTR) return 0;
if (__dn_expand(packet, (const unsigned char *)packet + 512,
- data, tmp, sizeof tmp) > 0)
- strcpy(c, tmp);
+ data, c, 256) <= 0)
+ *(char *)c = 0;
return 0;