From 00837731d254908a841d69298a4f9f077babaf24 Mon Sep 17 00:00:00 2001 From: Stefan Weil Date: Fri, 20 Nov 2015 08:42:33 +0100 Subject: [PATCH] eepro100: Prevent two endless loops http://lists.nongnu.org/archive/html/qemu-devel/2015-11/msg04592.html shows an example how an endless loop in function action_command can be achieved. During my code review, I noticed a 2nd case which can result in an endless loop. Reported-by: Qinghao Tang Signed-off-by: Stefan Weil Signed-off-by: Jason Wang --- tools/qemu-xen-traditional/hw/eepro100.c | 16 ++++++++++++++++ 1 files changed, 16 insertions(+), 0 deletions(-) diff --git a/tools/qemu-xen-traditional/hw/eepro100.c b/tools/qemu-xen-traditional/hw/eepro100.c index 60333b7..685a478 100644 --- a/tools/qemu-xen-traditional/hw/eepro100.c +++ b/tools/qemu-xen-traditional/hw/eepro100.c @@ -774,6 +774,11 @@ static void tx_command(EEPRO100State *s) uint32_t tx_buffer_address = ldl_phys(tbd_address); uint16_t tx_buffer_size = lduw_phys(tbd_address + 4); //~ uint16_t tx_buffer_el = lduw_phys(tbd_address + 6); + if (tx_buffer_size == 0) { + /* Prevent an endless loop. */ + logout("loop in %s:%u\n", __FILE__, __LINE__); + break; + } tbd_address += 8; logout ("TBD (simplified mode): buffer address 0x%08x, size 0x%04x\n", -- 1.7.0.4