Re: [PATCH 132/190] Revert "net: fujitsu: fix a potential NULL pointer dereference"

From: Greg Kroah-Hartman
Date: Wed Apr 28 2021 - 02:38:15 EST


On Wed, Apr 28, 2021 at 07:54:34AM +0200, Dominik Brodowski wrote:
> Am Wed, Apr 28, 2021 at 07:40:49AM +0200 schrieb Greg Kroah-Hartman:
> > On Wed, Apr 21, 2021 at 03:00:07PM +0200, Greg Kroah-Hartman wrote:
> > > This reverts commit 9f4d6358e11bbc7b839f9419636188e4151fb6e4.
> > >
> > > Commits from @umn.edu addresses have been found to be submitted in "bad
> > > faith" to try to test the kernel community's ability to review "known
> > > malicious" changes. The result of these submissions can be found in a
> > > paper published at the 42nd IEEE Symposium on Security and Privacy
> > > entitled, "Open Source Insecurity: Stealthily Introducing
> > > Vulnerabilities via Hypocrite Commits" written by Qiushi Wu (University
> > > of Minnesota) and Kangjie Lu (University of Minnesota).
> > >
> > > Because of this, all submissions from this group must be reverted from
> > > the kernel tree and will need to be re-reviewed again to determine if
> > > they actually are a valid fix. Until that work is complete, remove this
> > > change to ensure that no problems are being introduced into the
> > > codebase.
> > >
> > > Cc: Kangjie Lu <kjlu@xxxxxxx>
> > > Cc: David S. Miller <davem@xxxxxxxxxxxxx>
> > > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> > > ---
> > > drivers/net/ethernet/fujitsu/fmvj18x_cs.c | 5 -----
> > > 1 file changed, 5 deletions(-)
> > >
> > > diff --git a/drivers/net/ethernet/fujitsu/fmvj18x_cs.c b/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
> > > index a7b7a4aace79..dc90c61fc827 100644
> > > --- a/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
> > > +++ b/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
> > > @@ -547,11 +547,6 @@ static int fmvj18x_get_hwinfo(struct pcmcia_device *link, u_char *node_id)
> > > return -1;
> > >
> > > base = ioremap(link->resource[2]->start, resource_size(link->resource[2]));
> > > - if (!base) {
> > > - pcmcia_release_window(link, link->resource[2]);
> > > - return -ENOMEM;
> > > - }
> > > -
> > > pcmcia_map_mem_page(link, link->resource[2], 0);
> > >
> > > /*
> > > --
> > > 2.31.1
> > >
> >
> > Original commit looks correct here, I'll drop the revert.
>
> NAK. The only caller of that function checks only for "== -1" as error
> condition, so this error is not handled correctly. So this patch was/is
> obviously broken.

Ah, missed that, thanks! I'll keep the revert and then submit a fix for
this properly.

Many thanks for the re-review.

greg k-h