From 11744862f27b9ba6488a247d2fd6bb83d9bc3c8d Mon Sep 17 00:00:00 2001 From: Pavel Pisa Date: Thu, 29 Jul 2021 14:33:27 +0200 Subject: [PATCH] hw/net/can: sja1000 fix buff2frame_bas and buff2frame_pel when dlc is out of std CAN 8 bytes MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Problem reported by openEuler fuzz-sig group. The buff2frame_bas function (hw\net\can\can_sja1000.c) infoleak(qemu5.x~qemu6.x) or stack-overflow(qemu 4.x). Reported-by: Qiang Ning Cc: qemu-stable@nongnu.org Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Pavel Pisa Signed-off-by: Jason Wang --- hw/net/can/can_sja1000.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/hw/net/can/can_sja1000.c b/hw/net/can/can_sja1000.c index 42d2f99dfb..34eea684ce 100644 --- a/hw/net/can/can_sja1000.c +++ b/hw/net/can/can_sja1000.c @@ -275,6 +275,10 @@ static void buff2frame_pel(const uint8_t *buff, qemu_can_frame *frame) } frame->can_dlc = buff[0] & 0x0f; + if (frame->can_dlc > 8) { + frame->can_dlc = 8; + } + if (buff[0] & 0x80) { /* Extended */ frame->can_id |= QEMU_CAN_EFF_FLAG; frame->can_id |= buff[1] << 21; /* ID.28~ID.21 */ @@ -311,6 +315,10 @@ static void buff2frame_bas(const uint8_t *buff, qemu_can_frame *frame) } frame->can_dlc = buff[1] & 0x0f; + if (frame->can_dlc > 8) { + frame->can_dlc = 8; + } + for (i = 0; i < frame->can_dlc; i++) { frame->data[i] = buff[2 + i]; }