2021-02-02 05:49:40

by Dan Carpenter

Subject: [PATCH] ceph: Fix an Oops in error handling

The "req" pointer is an error pointer and not NULL so this check needs
to be fixed.

Fixes: 1cf7fdf52d5a ("ceph: convert readpage to fscache read helper")
Signed-off-by: Dan Carpenter <[email protected]>
---
fs/ceph/addr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 5eec6f66fe52..fb0238a4d34f 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -273,7 +273,7 @@ static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq)
if (err)
iput(inode);
out:
- if (req)
+ if (!IS_ERR_OR_NULL(req))
ceph_osdc_put_request(req);
if (err)
netfs_subreq_terminated(subreq, err);
--
2.29.2

2021-02-02 21:25:59

by Ilya Dryomov

Subject: Re: [PATCH] ceph: Fix an Oops in error handling

On Tue, Feb 2, 2021 at 6:47 AM Dan Carpenter <[email protected]> wrote:
>
> The "req" pointer is an error pointer and not NULL so this check needs
> to be fixed.
>
> Fixes: 1cf7fdf52d5a ("ceph: convert readpage to fscache read helper")
> Signed-off-by: Dan Carpenter <[email protected]>
> ---
> fs/ceph/addr.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
> index 5eec6f66fe52..fb0238a4d34f 100644
> --- a/fs/ceph/addr.c
> +++ b/fs/ceph/addr.c
> @@ -273,7 +273,7 @@ static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq)
> if (err)
> iput(inode);
> out:
> - if (req)
> + if (!IS_ERR_OR_NULL(req))
> ceph_osdc_put_request(req);
> if (err)
> netfs_subreq_terminated(subreq, err);

Hi Dan,

I think a better fix would be to set req to NULL in the offending
IS_ERR branch since ceph_osdc_new_request() never returns NULL or
use two separate goto labels.

While at it, the initialization of req and the check on req before
calling ceph_osdc_put_request() are redundant.

Thanks,

Ilya

2021-02-02 21:26:00

by Jeff Layton

Subject: Re: [PATCH] ceph: Fix an Oops in error handling

On Tue, 2021-02-02 at 08:47 +0300, Dan Carpenter wrote:
> The "req" pointer is an error pointer and not NULL so this check needs
> to be fixed.
>
> Fixes: 1cf7fdf52d5a ("ceph: convert readpage to fscache read helper")
> Signed-off-by: Dan Carpenter <[email protected]>
> ---
> ?fs/ceph/addr.c | 2 +-
> ?1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
> index 5eec6f66fe52..fb0238a4d34f 100644
> --- a/fs/ceph/addr.c
> +++ b/fs/ceph/addr.c
> @@ -273,7 +273,7 @@ static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq)
> ? if (err)
> ? iput(inode);
> ?out:
> - if (req)
> + if (!IS_ERR_OR_NULL(req))
> ? ceph_osdc_put_request(req);
> ? if (err)
> ? netfs_subreq_terminated(subreq, err);

Good catch.

David, could you take this into your fscache-next branch?

Reviewed-by: Jeff Layton <[email protected]>

2021-02-02 22:23:54

by Dan Carpenter

Subject: Re: [PATCH] ceph: Fix an Oops in error handling

On Tue, Feb 02, 2021 at 07:37:57AM -0500, Jeff Layton wrote:
> On Tue, 2021-02-02 at 08:47 +0300, Dan Carpenter wrote:
> > The "req" pointer is an error pointer and not NULL so this check needs
> > to be fixed.
> >
> > Fixes: 1cf7fdf52d5a ("ceph: convert readpage to fscache read helper")
> > Signed-off-by: Dan Carpenter <[email protected]>
> > ---
> > ?fs/ceph/addr.c | 2 +-
> > ?1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
> > index 5eec6f66fe52..fb0238a4d34f 100644
> > --- a/fs/ceph/addr.c
> > +++ b/fs/ceph/addr.c
> > @@ -273,7 +273,7 @@ static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq)
> > ? if (err)
> > ? iput(inode);
> > ?out:
> > - if (req)
> > + if (!IS_ERR_OR_NULL(req))
> > ? ceph_osdc_put_request(req);
> > ? if (err)
> > ? netfs_subreq_terminated(subreq, err);
>
> Good catch.
>
> David, could you take this into your fscache-next branch?
>
> Reviewed-by: Jeff Layton <[email protected]>

Jeff sent a different fix for this. Let's just apply his instead.

regards,
dan carpenter