diff options
| author | Mikulas Patocka <mpatocka@redhat.com> | 2021-03-26 21:32:32 +0300 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2021-03-26 21:51:50 +0300 |
| commit | 4edbe1d7bcffcd6269f3b5eb63f710393ff2ec7a (patch) | |
| tree | acb59de82e8576d658a2a2eb47b520c126f87ebd | |
| parent | 5424a0b867e65f1ecf34ffe88d091a4fcbb35bc1 (diff) | |
| download | linux-4edbe1d7bcffcd6269f3b5eb63f710393ff2ec7a.tar.xz | |
dm ioctl: fix out of bounds array access when no devices
If there are not any dm devices, we need to zero the "dev" argument in
the first structure dm_name_list. However, this can cause out of
bounds write, because the "needed" variable is zero and len may be
less than eight.
Fix this bug by reporting DM_BUFFER_FULL_FLAG if the result buffer is
too small to hold the "nl->dev" value.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| -rw-r--r-- | drivers/md/dm-ioctl.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 5e306bba4375..1ca65b434f1f 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -529,7 +529,7 @@ static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_ * Grab our output buffer. */ nl = orig_nl = get_result_buffer(param, param_size, &len); - if (len < needed) { + if (len < needed || len < sizeof(nl->dev)) { param->flags |= DM_BUFFER_FULL_FLAG; goto out; } |