diff options
| author | Adrian Salido <salidoa@google.com> | 2017-04-27 10:32:55 -0700 |
|---|---|---|
| committer | Mark Salyzyn <salyzyn@google.com> | 2017-06-12 08:33:35 -0700 |
| commit | e468d713930a359e99219be69283ac14019ce859 (patch) | |
| tree | 764b675bf26e5bbdcdac92712c7863c6873bd965 | |
| parent | 5c6ada561458b4e59d4b6029925f3180a046440c (diff) | |
| download | tegra-e468d713930a359e99219be69283ac14019ce859.tar.gz | |
UPSTREAM: dm ioctl: prevent stack leak in dm ioctl call
commit 4617f564c06117c7d1b611be49521a4430042287 upstream.
When calling a dm ioctl that doesn't process any data
(IOCTL_FLAGS_NO_PARAMS), the contents of the data field in struct
dm_ioctl are left initialized. Current code is incorrectly extending
the size of data copied back to user, causing the contents of kernel
stack to be leaked to user. Fix by only copying contents before data
and allow the functions processing the ioctl to override.
Signed-off-by: Adrian Salido <salidoa@google.com>
Reviewed-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bug: 35644370
Change-Id: I4f9a857d0f851ed37eff2d7b0f04e92dc6cf3b56
| -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 1debe0433ec6..31f849931515 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -1767,7 +1767,7 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user) if (r) goto out; - param->data_size = sizeof(*param); + param->data_size = offsetof(struct dm_ioctl, data); r = fn(param, input_param_size); if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) && |