[PATCH v2] daemon.c: fix segfault on OS X
- From
Benjamin Kramer <benny.kra@googlemail.com>
- Date
- Apr 27, 2009, 13:59 UTC
- Message-ID
- <49F5BA55.3060606@googlemail.com>
- In-Reply-To
- <7vy6tmbzj3.fsf@gitster.siamese.dyndns.org>
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(-)
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