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| author | Dan Carpenter <dan.carpenter@oracle.com> | 2021-12-08 18:09:56 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-12-22 11:32:36 +0300 |
| commit | ebbbc5fea3f648175df1aa3f127c78eb0252cc2a (patch) | |
| tree | e3caf65dea3f06b3aee95d70d97f582892923d9d /drivers/vdpa | |
| parent | e6c67560b4341914bec32ec536e931c22062af65 (diff) | |
| download | linux-ebbbc5fea3f648175df1aa3f127c78eb0252cc2a.tar.xz | |
vduse: check that offset is within bounds in get_config()
commit dc1db0060c02d119fd4196924eff2d1129e9a442 upstream.
This condition checks "len" but it does not check "offset" and that
could result in an out of bounds read if "offset > dev->config_size".
The problem is that since both variables are unsigned the
"dev->config_size - offset" subtraction would result in a very high
unsigned value.
I think these checks might not be necessary because "len" and "offset"
are supposed to already have been validated using the
vhost_vdpa_config_validate() function. But I do not know the code
perfectly, and I like to be safe.
Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211208150956.GA29160@kili
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/vdpa')
| -rw-r--r-- | drivers/vdpa/vdpa_user/vduse_dev.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index 17064d9f5a9c..8c3de5a76282 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -655,7 +655,8 @@ static void vduse_vdpa_get_config(struct vdpa_device *vdpa, unsigned int offset, { struct vduse_dev *dev = vdpa_to_vduse(vdpa); - if (len > dev->config_size - offset) + if (offset > dev->config_size || + len > dev->config_size - offset) return; memcpy(buf, dev->config + offset, len); |