From: Fabian Vogt Date: Wed, 27 Jul 2022 09:44:07 +0000 (+0200) Subject: nscd: Fix netlink cache invalidation if epoll is used [BZ #29415] X-Git-Tag: glibc-2.37~392 X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=02ca25fef2785974011e9c5beecc99b900b69fd7;p=glibc.git nscd: Fix netlink cache invalidation if epoll is used [BZ #29415] Processes cache network interface information such as whether IPv4 or IPv6 are enabled. This is only checked again if the "netlink timestamp" provided by nscd changed, which is triggered by netlink socket activity. However, in the epoll handler for the netlink socket, it was missed to assign the new timestamp to the nscd database. The handler for plain poll did that properly, copy that over. This bug caused that e.g. processes which started before network configuration got unusuable addresses from getaddrinfo, like IPv6 only even though only IPv4 is available: https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/1041 It's a bit hard to reproduce, so I verified this by checking the timestamp on calls to __check_pf manually. Without this patch it's stuck at 1, now it's increasing on network changes as expected. Signed-off-by: Fabian Vogt --- diff --git a/nscd/connections.c b/nscd/connections.c index 61d1674eb4..531d2e83df 100644 --- a/nscd/connections.c +++ b/nscd/connections.c @@ -2284,7 +2284,8 @@ main_loop_epoll (int efd) sizeof (buf))) != -1) ; - __bump_nl_timestamp (); + dbs[hstdb].head->extra_data[NSCD_HST_IDX_CONF_TIMESTAMP] + = __bump_nl_timestamp (); } # endif else