From e8ce12d9eaeedeb7f8d9debcd4c9b993903f1abb Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Wed, 24 Feb 2016 16:08:08 +0800 Subject: [PATCH] usb-redirect: Avoid double free of data If dropping packets, data is freed, the caller's loop should not continue. Reported by ccc-analyzer. Signed-off-by: Fam Zheng Message-id: 1456301288-1592-1-git-send-email-famz@redhat.com Signed-off-by: Gerd Hoffmann --- hw/usb/redirect.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c index d0f7cb8139..38a539311b 100644 --- a/hw/usb/redirect.c +++ b/hw/usb/redirect.c @@ -447,7 +447,7 @@ static USBPacket *usbredir_find_packet_by_id(USBRedirDevice *dev, return p; } -static void bufp_alloc(USBRedirDevice *dev, uint8_t *data, uint16_t len, +static int bufp_alloc(USBRedirDevice *dev, uint8_t *data, uint16_t len, uint8_t status, uint8_t ep, void *free_on_destroy) { struct buf_packet *bufp; @@ -464,7 +464,7 @@ static void bufp_alloc(USBRedirDevice *dev, uint8_t *data, uint16_t len, if (dev->endpoint[EP2I(ep)].bufpq_size > dev->endpoint[EP2I(ep)].bufpq_target_size) { free(data); - return; + return -1; } dev->endpoint[EP2I(ep)].bufpq_dropping_packets = 0; } @@ -477,6 +477,7 @@ static void bufp_alloc(USBRedirDevice *dev, uint8_t *data, uint16_t len, bufp->free_on_destroy = free_on_destroy; QTAILQ_INSERT_TAIL(&dev->endpoint[EP2I(ep)].bufpq, bufp, next); dev->endpoint[EP2I(ep)].bufpq_size++; + return 0; } static void bufp_free(USBRedirDevice *dev, struct buf_packet *bufp, @@ -2082,13 +2083,17 @@ static void usbredir_buffered_bulk_packet(void *priv, uint64_t id, status = usb_redir_success; free_on_destroy = NULL; for (i = 0; i < data_len; i += len) { + int r; if (len >= (data_len - i)) { len = data_len - i; status = buffered_bulk_packet->status; free_on_destroy = data; } /* bufp_alloc also adds the packet to the ep queue */ - bufp_alloc(dev, data + i, len, status, ep, free_on_destroy); + r = bufp_alloc(dev, data + i, len, status, ep, free_on_destroy); + if (r) { + break; + } } if (dev->endpoint[EP2I(ep)].pending_async_packet) {