From 0ac2e63575b5af918e333cc687bbd8e1ab7bb6fe Mon Sep 17 00:00:00 2001 From: Li Feng Date: Fri, 17 Apr 2020 18:17:07 +0800 Subject: [PATCH] vhost-user-blk: fix invalid memory access when s->inflight is freed, vhost_dev_free_inflight may try to access s->inflight->addr, it will retrigger the following issue. ==7309==ERROR: AddressSanitizer: heap-use-after-free on address 0x604001020d18 at pc 0x555555ce948a bp 0x7fffffffb170 sp 0x7fffffffb160 READ of size 8 at 0x604001020d18 thread T0 #0 0x555555ce9489 in vhost_dev_free_inflight /root/smartx/qemu-el7/qemu-test/hw/virtio/vhost.c:1473 #1 0x555555cd86eb in virtio_reset /root/smartx/qemu-el7/qemu-test/hw/virtio/virtio.c:1214 #2 0x5555560d3eff in virtio_pci_reset hw/virtio/virtio-pci.c:1859 #3 0x555555f2ac53 in device_set_realized hw/core/qdev.c:893 #4 0x5555561d572c in property_set_bool qom/object.c:1925 #5 0x5555561de8de in object_property_set_qobject qom/qom-qobject.c:27 #6 0x5555561d99f4 in object_property_set_bool qom/object.c:1188 #7 0x555555e50ae7 in qdev_device_add /root/smartx/qemu-el7/qemu-test/qdev-monitor.c:626 #8 0x555555e51213 in qmp_device_add /root/smartx/qemu-el7/qemu-test/qdev-monitor.c:806 #9 0x555555e8ff40 in hmp_device_add /root/smartx/qemu-el7/qemu-test/hmp.c:1951 #10 0x555555be889a in handle_hmp_command /root/smartx/qemu-el7/qemu-test/monitor.c:3404 #11 0x555555beac8b in monitor_command_cb /root/smartx/qemu-el7/qemu-test/monitor.c:4296 #12 0x555556433eb7 in readline_handle_byte util/readline.c:393 #13 0x555555be89ec in monitor_read /root/smartx/qemu-el7/qemu-test/monitor.c:4279 #14 0x5555563285cc in tcp_chr_read chardev/char-socket.c:470 #15 0x7ffff670b968 in g_main_context_dispatch (/lib64/libglib-2.0.so.0+0x4a968) #16 0x55555640727c in glib_pollfds_poll util/main-loop.c:215 #17 0x55555640727c in os_host_main_loop_wait util/main-loop.c:238 #18 0x55555640727c in main_loop_wait util/main-loop.c:497 #19 0x555555b2d0bf in main_loop /root/smartx/qemu-el7/qemu-test/vl.c:2013 #20 0x555555b2d0bf in main /root/smartx/qemu-el7/qemu-test/vl.c:4776 #21 0x7fffdd2eb444 in __libc_start_main (/lib64/libc.so.6+0x22444) #22 0x555555b3767a (/root/smartx/qemu-el7/qemu-test/x86_64-softmmu/qemu-system-x86_64+0x5e367a) 0x604001020d18 is located 8 bytes inside of 40-byte region [0x604001020d10,0x604001020d38) freed by thread T0 here: #0 0x7ffff6f00508 in __interceptor_free (/lib64/libasan.so.4+0xde508) #1 0x7ffff671107d in g_free (/lib64/libglib-2.0.so.0+0x5007d) previously allocated by thread T0 here: #0 0x7ffff6f00a88 in __interceptor_calloc (/lib64/libasan.so.4+0xdea88) #1 0x7ffff6710fc5 in g_malloc0 (/lib64/libglib-2.0.so.0+0x4ffc5) SUMMARY: AddressSanitizer: heap-use-after-free /root/smartx/qemu-el7/qemu-test/hw/virtio/vhost.c:1473 in vhost_dev_free_inflight Shadow bytes around the buggy address: 0x0c08801fc150: fa fa 00 00 00 00 04 fa fa fa fd fd fd fd fd fa 0x0c08801fc160: fa fa fd fd fd fd fd fd fa fa 00 00 00 00 04 fa 0x0c08801fc170: fa fa 00 00 00 00 00 01 fa fa 00 00 00 00 04 fa 0x0c08801fc180: fa fa 00 00 00 00 00 01 fa fa 00 00 00 00 00 01 0x0c08801fc190: fa fa 00 00 00 00 00 fa fa fa 00 00 00 00 04 fa =>0x0c08801fc1a0: fa fa fd[fd]fd fd fd fa fa fa fd fd fd fd fd fa 0x0c08801fc1b0: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fa 0x0c08801fc1c0: fa fa 00 00 00 00 00 fa fa fa fd fd fd fd fd fd 0x0c08801fc1d0: fa fa 00 00 00 00 00 01 fa fa fd fd fd fd fd fa 0x0c08801fc1e0: fa fa fd fd fd fd fd fa fa fa fd fd fd fd fd fd 0x0c08801fc1f0: fa fa 00 00 00 00 00 01 fa fa fd fd fd fd fd fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb ==7309==ABORTING Signed-off-by: Li Feng Message-Id: <20200417101707.14467-1-fengli@smartx.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Reviewed-by: Raphael Norwitz --- hw/block/vhost-user-blk.c | 4 ++++ hw/virtio/vhost.c | 2 +- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c index 17df5338e7..6c485d1c9e 100644 --- a/hw/block/vhost-user-blk.c +++ b/hw/block/vhost-user-blk.c @@ -441,7 +441,9 @@ reconnect: virtio_err: g_free(s->vhost_vqs); + s->vhost_vqs = NULL; g_free(s->inflight); + s->inflight = NULL; for (i = 0; i < s->num_queues; i++) { virtio_delete_queue(s->virtqs[i]); } @@ -462,7 +464,9 @@ static void vhost_user_blk_device_unrealize(DeviceState *dev, Error **errp) vhost_dev_cleanup(&s->dev); vhost_dev_free_inflight(s->inflight); g_free(s->vhost_vqs); + s->vhost_vqs = NULL; g_free(s->inflight); + s->inflight = NULL; for (i = 0; i < s->num_queues; i++) { virtio_delete_queue(s->virtqs[i]); diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index 01ebe12f28..aff98a0ede 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -1514,7 +1514,7 @@ void vhost_dev_set_config_notifier(struct vhost_dev *hdev, void vhost_dev_free_inflight(struct vhost_inflight *inflight) { - if (inflight->addr) { + if (inflight && inflight->addr) { qemu_memfd_free(inflight->addr, inflight->size, inflight->fd); inflight->addr = NULL; inflight->fd = -1;