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author | Marc-André Lureau <marcandre.lureau@redhat.com> | 2017-05-03 20:54:12 +0400 |
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committer | Michael S. Tsirkin <mst@redhat.com> | 2017-05-10 22:04:23 +0300 |
commit | 640601c7cb1b6b41d3e1a435b986266c2b71e9bc (patch) | |
tree | d69caf1951e0a50139db7c6b5397ca1af1cfe486 /contrib/libvhost-user/libvhost-user.h | |
parent | 60cd11024f41cc73175e651a2dfe09a3cade56bb (diff) | |
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libvhost-user: fix crash when rings aren't ready
Calling libvhost-user functions like vu_queue_get_avail_bytes() when the
queue doesn't yet have addresses will result in the crashes like the
following:
Program received signal SIGSEGV, Segmentation fault.
0x000055c414112ce4 in vring_avail_idx (vq=0x55c41582fd68, vq=0x55c41582fd68)
at /home/dgilbert/git/qemu/contrib/libvhost-user/libvhost-user.c:940
940 vq->shadow_avail_idx = vq->vring.avail->idx;
(gdb) p vq
$1 = (VuVirtq *) 0x55c41582fd68
(gdb) p vq->vring
$2 = {num = 0, desc = 0x0, avail = 0x0, used = 0x0, log_guest_addr = 0, flags = 0}
at /home/dgilbert/git/qemu/contrib/libvhost-user/libvhost-user.c:940
No locals.
at /home/dgilbert/git/qemu/contrib/libvhost-user/libvhost-user.c:960
num_heads = <optimized out>
out_bytes=out_bytes@entry=0x7fffd035d7c4, max_in_bytes=max_in_bytes@entry=0,
max_out_bytes=max_out_bytes@entry=0) at /home/dgilbert/git/qemu/contrib/libvhost-user/libvhost-user.c:1034
Add a pre-condition checks on vring.avail before accessing it.
Fix documentation and return type of vu_queue_empty() while at it.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'contrib/libvhost-user/libvhost-user.h')
-rw-r--r-- | contrib/libvhost-user/libvhost-user.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h index 156b50e..af02a31 100644 --- a/contrib/libvhost-user/libvhost-user.h +++ b/contrib/libvhost-user/libvhost-user.h @@ -327,13 +327,13 @@ void vu_queue_set_notification(VuDev *dev, VuVirtq *vq, int enable); bool vu_queue_enabled(VuDev *dev, VuVirtq *vq); /** - * vu_queue_enabled: + * vu_queue_empty: * @dev: a VuDev context * @vq: a VuVirtq queue * - * Returns: whether the queue is empty. + * Returns: true if the queue is empty or not ready. */ -int vu_queue_empty(VuDev *dev, VuVirtq *vq); +bool vu_queue_empty(VuDev *dev, VuVirtq *vq); /** * vu_queue_notify: |