2021-06-28 12:38:48

by Wang Shilong

Subject: [PATCH v2] fs: forbid invalid project ID

fileattr_set_prepare() should check if project ID
is valid, otherwise dqget() will return NULL for
such project ID quota.

Signed-off-by: Wang Shilong <[email protected]>
---
v1->v2: try to fix in the VFS
---
fs/ioctl.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/fs/ioctl.c b/fs/ioctl.c
index 1e2204fa9963..5db5b218637b 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -845,6 +845,9 @@ static int fileattr_set_prepare(struct inode *inode,
if (fa->fsx_cowextsize == 0)
fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;

+ if (!projid_valid(KPROJIDT_INIT(fa->fsx_projid)))
+ return -EINVAL;
+
return 0;
}

--
2.27.0

2021-06-28 23:43:38

by Dave Chinner

Subject: Re: [PATCH v2] fs: forbid invalid project ID

On Mon, Jun 28, 2021 at 08:38:01AM -0400, Wang Shilong wrote:
> fileattr_set_prepare() should check if project ID
> is valid, otherwise dqget() will return NULL for
> such project ID quota.
>
> Signed-off-by: Wang Shilong <[email protected]>
> ---
> v1->v2: try to fix in the VFS
> ---
> fs/ioctl.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/fs/ioctl.c b/fs/ioctl.c
> index 1e2204fa9963..5db5b218637b 100644
> --- a/fs/ioctl.c
> +++ b/fs/ioctl.c
> @@ -845,6 +845,9 @@ static int fileattr_set_prepare(struct inode *inode,
> if (fa->fsx_cowextsize == 0)
> fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;
>
> + if (!projid_valid(KPROJIDT_INIT(fa->fsx_projid)))
> + return -EINVAL;

This needs to go further up in this function in the section where
project IDs passed into this function are validated. Projids are
only allowed to be changed when current_user_ns() == &init_user_ns,
so this needs to be associated with that verification context.

This check should also use make_kprojid(), please, not open code
KPROJIDT_INIT.

Cheers,

Dave.
--
Dave Chinner
[email protected]

2021-07-01 15:41:45

by Wang Shilong

Subject: Re: [PATCH v2] fs: forbid invalid project ID

On Tue, Jun 29, 2021 at 6:34 AM Dave Chinner <[email protected]> wrote:
>
> On Mon, Jun 28, 2021 at 08:38:01AM -0400, Wang Shilong wrote:
> > fileattr_set_prepare() should check if project ID
> > is valid, otherwise dqget() will return NULL for
> > such project ID quota.
> >
> > Signed-off-by: Wang Shilong <[email protected]>
> > ---
> > v1->v2: try to fix in the VFS
> > ---
> > fs/ioctl.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/fs/ioctl.c b/fs/ioctl.c
> > index 1e2204fa9963..5db5b218637b 100644
> > --- a/fs/ioctl.c
> > +++ b/fs/ioctl.c
> > @@ -845,6 +845,9 @@ static int fileattr_set_prepare(struct inode *inode,
> > if (fa->fsx_cowextsize == 0)
> > fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;
> >
> > + if (!projid_valid(KPROJIDT_INIT(fa->fsx_projid)))
> > + return -EINVAL;
>
> This needs to go further up in this function in the section where
> project IDs passed into this function are validated. Projids are
> only allowed to be changed when current_user_ns() == &init_user_ns,
> so this needs to be associated with that verification context.
>
> This check should also use make_kprojid(), please, not open code
> KPROJIDT_INIT.

You are right, let me send a V3

>
> Cheers,
>
> Dave.
> --
> Dave Chinner
> [email protected]