From 72e7bb00aef5e81d870d44e3697d0a247a3bb3af Mon Sep 17 00:00:00 2001 From: Xiao Wang Date: Fri, 17 May 2019 07:29:35 +0200 Subject: [PATCH 1/9] rtl8139: fix possible out of bound access RH-Author: Xiao Wang Message-id: <1558078177-372-2-git-send-email-jasowang@redhat.com> Patchwork-id: 88013 O-Subject: [RHEL7.7 qemu-kvm-rhev PATCH 1/3] rtl8139: fix possible out of bound access Bugzilla: 1636780 RH-Acked-by: Thomas Huth RH-Acked-by: Jens Freimann RH-Acked-by: Maxime Coquelin RH-Acked-by: Michael S. Tsirkin Bugzilla: 1636727 In rtl8139_do_receive(), we try to assign size_ to size which converts from size_t to integer. This will cause troubles when size_ is greater INT_MAX, this will lead a negative value in size and it can then pass the check of size < MIN_BUF_SIZE which may lead out of bound access of for both buf and buf1. Fixing by converting the type of size to size_t. CC: qemu-stable@nongnu.org Reported-by: Daniel Shapira Reviewed-by: Michael S. Tsirkin Signed-off-by: Jason Wang (cherry picked from commit 1a326646fef38782e5542280040ec3ea23e4a730) Signed-off-by: Miroslav Rezanina --- hw/net/rtl8139.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/hw/net/rtl8139.c b/hw/net/rtl8139.c index bc37326..d343fb9 100644 --- a/hw/net/rtl8139.c +++ b/hw/net/rtl8139.c @@ -817,7 +817,7 @@ static ssize_t rtl8139_do_receive(NetClientState *nc, const uint8_t *buf, size_t RTL8139State *s = qemu_get_nic_opaque(nc); PCIDevice *d = PCI_DEVICE(s); /* size is the length of the buffer passed to the driver */ - int size = size_; + size_t size = size_; const uint8_t *dot1q_buf = NULL; uint32_t packet_header = 0; @@ -826,7 +826,7 @@ static ssize_t rtl8139_do_receive(NetClientState *nc, const uint8_t *buf, size_t static const uint8_t broadcast_macaddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; - DPRINTF(">>> received len=%d\n", size); + DPRINTF(">>> received len=%zu\n", size); /* test if board clock is stopped */ if (!s->clock_enabled) @@ -1035,7 +1035,7 @@ static ssize_t rtl8139_do_receive(NetClientState *nc, const uint8_t *buf, size_t if (size+4 > rx_space) { - DPRINTF("C+ Rx mode : descriptor %d size %d received %d + 4\n", + DPRINTF("C+ Rx mode : descriptor %d size %d received %zu + 4\n", descriptor, rx_space, size); s->IntrStatus |= RxOverflow; @@ -1148,7 +1148,7 @@ static ssize_t rtl8139_do_receive(NetClientState *nc, const uint8_t *buf, size_t if (avail != 0 && RX_ALIGN(size + 8) >= avail) { DPRINTF("rx overflow: rx buffer length %d head 0x%04x " - "read 0x%04x === available 0x%04x need 0x%04x\n", + "read 0x%04x === available 0x%04x need 0x%04zx\n", s->RxBufferSize, s->RxBufAddr, s->RxBufPtr, avail, size + 8); s->IntrStatus |= RxOverflow; -- 1.8.3.1