[PATCH v2] daemon.c: fix segfault on OS X
On OS X (and maybe other unices), getaddrinfo(3) returns NULL in the ai_canonname field if it's called with an IP address for the hostname. We'll now use the IP address for the hostname if ai_canonname was NULL, this also matches the behaviour on Linux.
steps to reproduce: $ git daemon --export-all $ git clone git://127.0.0.1/frotz => git daemon's fork (silently) segfaults.
Remove the pointless loop while at it. There is only one iteration because of the break; on the last line and there are no continues.
Signed-off-by: Benjamin Kramer <benny.kra@googlemail.com>
---
Junio C Hamano wrote:
Show 5 quoted lines
> But the part your patch touches is about supporting virtual hosting via
> pattern interpolation, and the daemon will still segfault even with your
> patch when somebody uses %CH expansion, because canon_hostname is left as
> NULL, won't it? I suspect in such a case it might be safer to use a copy
> of the ip_address or something.
It doesn't segfault but it just assumes an empty hostname:
$ git daemon --verbose --export-all --interpolated-path=%CH/%D
[3251] Connection from 127.0.0.1:49423
[3251] Extended attributes (16 bytes) exist <host=127.0.0.1>
[3251] Request upload-pack for '/frotz'
[3251] Interpolated dir '//frotz'This upated patch uses a copy of ip_address. I did a quick test on my Linux box and it looks like Linux' getaddrinfo(3) always returns the IP address in ai_canonname instead of NULL when it is called with an IP address hostname.
$ git daemon --verbose --export-all --interpolated-path=%CH/%D
[3871] Connection from 127.0.0.1:49427
[3871] Extended attributes (16 bytes) exist <host=127.0.0.1>
[3871] Request upload-pack for '/frotz'
[3871] Interpolated dir '127.0.0.1//frotz'Btw, if I connect to an IPv6 host with interpolated-path=%IP the IP address gets converted to 0.0.0.0. Is this desired behaviour or yet another bug?
(I hope thunderbird didn't f*ck up the formatting this time)
daemon.c | 28 ++++++++++++++--------------
1 files changed, 14 insertions(+), 14 deletions(-)
Show changes to daemon.c +14 −14
diff --git a/daemon.c b/daemon.c
index 13401f1..daa4c8e 100644
--- a/daemon.c
+++ b/daemon.c
@@ -444,27 +444,27 @@ static void parse_extra_args(char *extra_args, int buflen)
if (hostname) {
#ifndef NO_IPV6
struct addrinfo hints;
- struct addrinfo *ai, *ai0;
+ struct addrinfo *ai;
int gai;
static char addrbuf[HOST_NAME_MAX + 1];
memset(&hints, 0, sizeof(hints));
hints.ai_flags = AI_CANONNAME;
- gai = getaddrinfo(hostname, 0, &hints, &ai0);
+ gai = getaddrinfo(hostname, 0, &hints, &ai);
if (!gai) {
- for (ai = ai0; ai; ai = ai->ai_next) {
- struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
-
- inet_ntop(AF_INET, &sin_addr->sin_addr,
- addrbuf, sizeof(addrbuf));
- free(canon_hostname);
- canon_hostname = xstrdup(ai->ai_canonname);
- free(ip_address);
- ip_address = xstrdup(addrbuf);
- break;
- }
- freeaddrinfo(ai0);
+ struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
+
+ inet_ntop(AF_INET, &sin_addr->sin_addr,
+ addrbuf, sizeof(addrbuf));
+ free(ip_address);
+ ip_address = xstrdup(addrbuf);
+
+ free(canon_hostname);
+ canon_hostname = xstrdup(ai->ai_canonname ?
+ ai->ai_canonname : ip_address);
+
+ freeaddrinfo(ai);
}
#else
struct hostent *hent;
--
1.6.3.rc3.1.g35108