Re: [PATCH 02/13] ppc/cell: use get_unused_fd_flags(0) instead ofget_unused_fd()

From: Yann Droneaud
Date: Mon Jan 13 2014 - 04:31:08 EST


Hi Benjamin,

Le lundi 13 janvier 2014 Ã 10:06 +1100, Benjamin Herrenschmidt a Ãcrit :
> On Tue, 2013-07-02 at 18:39 +0200, Yann Droneaud wrote:
> > Macro get_unused_fd() is used to allocate a file descriptor with
> > default flags. Those default flags (0) can be "unsafe":
> > O_CLOEXEC must be used by default to not leak file descriptor
> > across exec().
> >
> > Instead of macro get_unused_fd(), functions anon_inode_getfd()
> > or get_unused_fd_flags() should be used with flags given by userspace.
> > If not possible, flags should be set to O_CLOEXEC to provide userspace
> > with a default safe behavor.
> >
> > In a further patch, get_unused_fd() will be removed so that
> > new code start using anon_inode_getfd() or get_unused_fd_flags()
> > with correct flags.
> >
> > This patch replaces calls to get_unused_fd() with equivalent call to
> > get_unused_fd_flags(0) to preserve current behavor for existing code.
> >
> > The hard coded flag value (0) should be reviewed on a per-subsystem basis,
> > and, if possible, set to O_CLOEXEC.
> >
> > Signed-off-by: Yann Droneaud <ydroneaud@xxxxxxxxxx>
>
> Should I merge this (v5 on patchwork) or let Al do it ?
>

Please merge it directly: patches from the previous patchsets were
picked individually by each subsystem maintainer after proper review
regarding setting close on exec flag by default.

> Acked-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
>

Thanks a lot.

> > ---
> > arch/powerpc/platforms/cell/spufs/inode.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c
> > index f390042..88df441 100644
> > --- a/arch/powerpc/platforms/cell/spufs/inode.c
> > +++ b/arch/powerpc/platforms/cell/spufs/inode.c
> > @@ -301,7 +301,7 @@ static int spufs_context_open(struct path *path)
> > int ret;
> > struct file *filp;
> >
> > - ret = get_unused_fd();
> > + ret = get_unused_fd_flags(0);
> > if (ret < 0)
> > return ret;
> >
> > @@ -518,7 +518,7 @@ static int spufs_gang_open(struct path *path)
> > int ret;
> > struct file *filp;
> >
> > - ret = get_unused_fd();
> > + ret = get_unused_fd_flags(0);
> > if (ret < 0)
> > return ret;
> >
>
>

Note:
latest patch (from v5 patchset) is at
http://lkml.kernel.org/r/fe27abcfab5563d36a3e5e58ff36e5500c39be6a.1388952061.git.ydroneaud@xxxxxxxxxx
v5 patchset is at
http://lkml.kernel.org/r/cover.1388952061.git.ydroneaud@xxxxxxxxxx

Regards.

--
Yann Droneaud
OPTEYA


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