From fc438d74b7a9341682a4b5841dc0186629e61ac1 Mon Sep 17 00:00:00 2001 From: Milan Broz Date: Thu, 11 Aug 2011 12:57:10 +0000 Subject: [PATCH] Never ever use uninitialised descriptors if pipe() fails (because of maximum open count fd exceeded or so). Better return busy message, so even clients fail in more controlled way. Without patch, clvmd crashes with various strange backtraces if under heavy load of connection requests. https://bugzilla.redhat.com/show_bug.cgi?id=698393 https://bugzilla.redhat.com/show_bug.cgi?id=697945 (It still can OOM but that's different issue.) --- WHATS_NEW | 1 + daemons/clvmd/clvmd.c | 14 ++++++++++++-- 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/WHATS_NEW b/WHATS_NEW index 85398adbe..9c53e390c 100644 --- a/WHATS_NEW +++ b/WHATS_NEW @@ -1,5 +1,6 @@ Version 2.02.87 - =============================== + If pipe in clvmd fails, return busy instead of using uninitialised descriptors. Add dmeventd monitoring shared library for RAID. Add RAID metadata devices to considered devices in _add_lv_to_dtree. Fix renaming of RAID logical volumes. diff --git a/daemons/clvmd/clvmd.c b/daemons/clvmd/clvmd.c index 07883eaa7..cffb74565 100644 --- a/daemons/clvmd/clvmd.c +++ b/daemons/clvmd/clvmd.c @@ -1263,9 +1263,19 @@ static int read_from_local_sock(struct local_client *thisfd) } /* Create a pipe and add the reading end to our FD list */ - if (pipe(comms_pipe)) + if (pipe(comms_pipe)) { + struct clvm_header reply; DEBUGLOG("creating pipe failed: %s\n", strerror(errno)); - + reply.cmd = CLVMD_CMD_REPLY; + reply.status = EBUSY; + reply.arglen = 0; + reply.flags = 0; + send_message(&reply, sizeof(reply), our_csid, + thisfd->fd, + "Error sending EBUSY reply to local user"); + return len; + } + newfd = malloc(sizeof(struct local_client)); if (!newfd) { struct clvm_header reply;