diff options
| author | Dan Carpenter <dancarpenter@oracle.com> | 2021-02-17 09:04:34 +0300 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2021-03-02 16:55:47 +0100 |
| commit | 5011c5a663b9c6d6aff3d394f11049b371199627 (patch) | |
| tree | 30158953f67cebabb9db0535a9c37e1c0f4c03f5 /fs/btrfs/ioctl.c | |
| parent | 4f6a49de64fd1b1dba5229c02047376da7cf24fd (diff) | |
btrfs: validate qgroup inherit for SNAP_CREATE_V2 ioctl
The problem is we're copying "inherit" from user space but we don't
necessarily know that we're copying enough data for a 64 byte
struct. Then the next problem is that 'inherit' has a variable size
array at the end, and we have to verify that array is the size we
expected.
Fixes: 6f72c7e20dba ("Btrfs: add qgroup inheritance")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/ioctl.c')
| -rw-r--r-- | fs/btrfs/ioctl.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index a8c60d46d19c..1b837c08ca90 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1935,7 +1935,10 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, if (vol_args->flags & BTRFS_SUBVOL_RDONLY) readonly = true; if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { - if (vol_args->size > PAGE_SIZE) { + u64 nums; + + if (vol_args->size < sizeof(*inherit) || + vol_args->size > PAGE_SIZE) { ret = -EINVAL; goto free_args; } @@ -1944,6 +1947,20 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, ret = PTR_ERR(inherit); goto free_args; } + + if (inherit->num_qgroups > PAGE_SIZE || + inherit->num_ref_copies > PAGE_SIZE || + inherit->num_excl_copies > PAGE_SIZE) { + ret = -EINVAL; + goto free_inherit; + } + + nums = inherit->num_qgroups + 2 * inherit->num_ref_copies + + 2 * inherit->num_excl_copies; + if (vol_args->size != struct_size(inherit, qgroups, nums)) { + ret = -EINVAL; + goto free_inherit; + } } ret = __btrfs_ioctl_snap_create(file, vol_args->name, vol_args->fd, |