+ arch-sparc-kernel-eliminate-what-looks-like-a-null-pointer-dereference.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     arch/sparc/kernel: eliminate what looks like a NULL pointer dereference
has been added to the -mm tree.  Its filename is
     arch-sparc-kernel-eliminate-what-looks-like-a-null-pointer-dereference.patch

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*** Remember to use Documentation/SubmitChecklist when testing your code ***

See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this

The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/

------------------------------------------------------
Subject: arch/sparc/kernel: eliminate what looks like a NULL pointer dereference
From: Julia Lawall <julia@diku.dk>

At the point of the test, action cannot be NULL, as it has been
dereferenced in the code just above.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
expression E,E1;
identifier f;
statement S1,S2,S3;
@@

if ((E == NULL && ...) || ...)
{
  ... when != if (...) S1 else S2
      when != E = E1
* E->f
  ... when any
}
else S3
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/sparc/kernel/sun4d_irq.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN arch/sparc/kernel/sun4d_irq.c~arch-sparc-kernel-eliminate-what-looks-like-a-null-pointer-dereference arch/sparc/kernel/sun4d_irq.c
--- a/arch/sparc/kernel/sun4d_irq.c~arch-sparc-kernel-eliminate-what-looks-like-a-null-pointer-dereference
+++ a/arch/sparc/kernel/sun4d_irq.c
@@ -183,7 +183,7 @@ void sun4d_free_irq(unsigned int irq, vo
 		goto out_unlock;
 	}
 	
-	if (action && tmp)
+	if (tmp)
 		tmp->next = action->next;
 	else
 		*actionp = action->next;
_

Patches currently in -mm which might be from julia@diku.dk are

origin.patch
linux-next.patch
arch-x86-kernel-add-missing-spin_unlock.patch
arch-x86-kernel-add-missing-spin_unlock-fix2.patch
fs-btrfs-use-memdup_user.patch
fs-btrfs-use-err_cast.patch
drivers-media-use-memdup_user.patch
drivers-media-video-pvrusb2-add-missing-mutex_unlock.patch
drivers-video-omap2-displays-add-missing-mutex_unlock.patch
drivers-i2c-use-memdup_user.patch
arch-ia64-kvm-add-missing-spin_unlock.patch
drivers-ide-use-memdup_user.patch
fs-ubifs-use-err_cast.patch
drivers-net-wireless-prism54-use-memdup_user.patch
fs-ocfs2-dlm-add-missing-spin_unlock.patch
drivers-s390-net-use-memdup_user.patch
drivers-scsi-libsas-use-sam_good.patch
drivers-scsi-remove-unnecessary-null-test.patch
drivers-message-move-dereference-after-null-test.patch
drivers-scsi-correct-the-size-argument-to-kmalloc.patch
drivers-scsi-use-memdup_user.patch
drivers-block-use-memdup_user.patch
drivers-staging-dream-camera-use-memdup_user.patch
drivers-staging-vme-bridges-add-missing-unlocks.patch
drivers-usb-gadget-use-memdup_user.patch
mm-use-memdup_user.patch
mm-use-err_cast.patch
drivers-message-i2o-exec-osmc-add-missing-mutex_unlock.patch
drivers-char-n_gsmc-add-missing-spin_unlock_irqrestore.patch
drivers-usb-serial-eliminate-a-null-pointer-dereference.patch
arch-sparc-kernel-eliminate-what-looks-like-a-null-pointer-dereference.patch
drivers-dma-eliminate-a-null-pointer-dereference.patch
drivers-media-eliminate-a-null-pointer-dereference.patch
drivers-staging-eliminate-a-null-pointer-dereference.patch