From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39813) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gF4N3-0004VO-OK for qemu-devel@nongnu.org; Tue, 23 Oct 2018 17:37:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gF4My-0003Y8-D3 for qemu-devel@nongnu.org; Tue, 23 Oct 2018 17:37:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57316) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gF4Mx-0003Uy-Sr for qemu-devel@nongnu.org; Tue, 23 Oct 2018 17:37:44 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id CE474C04F2AE for ; Tue, 23 Oct 2018 21:37:42 +0000 (UTC) References: <20181023213600.364086-1-eblake@redhat.com> From: Paolo Bonzini Message-ID: Date: Tue, 23 Oct 2018 23:37:32 +0200 MIME-Version: 1.0 In-Reply-To: <20181023213600.364086-1-eblake@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] vl: Avoid crash when -mon is underspecified List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake , qemu-devel@nongnu.org Cc: peterx@redhat.com, armbru@redhat.com, marcandre.lureau@redhat.com On 23/10/2018 23:35, Eric Blake wrote: > A quick coredump on an incomplete command line: > ./x86_64-softmmu/qemu-system-x86_64 -mon mode=control,pretty=on > > #0 0x00007ffff723d9e4 in g_str_hash () at /lib64/libglib-2.0.so.0 > #1 0x00007ffff723ce38 in g_hash_table_lookup () at /lib64/libglib-2.0.so.0 > #2 0x0000555555cc0073 in object_class_property_find (klass=0x5555566a94b0, name=0x0, errp=0x0) at qom/object.c:1135 > #3 0x0000555555cc004b in object_class_property_find (klass=0x5555566a9440, name=0x0, errp=0x0) at qom/object.c:1129 > #4 0x0000555555cbfe6e in object_property_find (obj=0x5555568348c0, name=0x0, errp=0x0) at qom/object.c:1080 > #5 0x0000555555cc183d in object_resolve_path_component (parent=0x5555568348c0, part=0x0) at qom/object.c:1762 > #6 0x0000555555d82071 in qemu_chr_find (name=0x0) at chardev/char.c:802 > #7 0x00005555559d77cb in mon_init_func (opaque=0x0, opts=0x5555566b65a0, errp=0x0) at vl.c:2291 > > Fix it to instead fail gracefully. > > Signed-off-by: Eric Blake > --- > vl.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/vl.c b/vl.c > index 4e25c78bff0..2ed8672eb79 100644 > --- a/vl.c > +++ b/vl.c > @@ -2288,6 +2288,10 @@ static int mon_init_func(void *opaque, QemuOpts *opts, Error **errp) > } > > chardev = qemu_opt_get(opts, "chardev"); > + if (!chardev) { > + error_report("chardev is required"); > + exit(1); > + } > chr = qemu_chr_find(chardev); > if (chr == NULL) { > error_report("chardev \"%s\" not found", chardev); > Reviewed-by: Paolo Bonzini