Messages in this thread | | | Date | Mon, 16 Dec 2013 23:26:02 -0800 | Subject | Re: [PATCH 2/3] staging: ion: Fix possible null pointer dereference | From | Colin Cross <> |
| |
On Mon, Dec 16, 2013 at 9:07 PM, John Stultz <john.stultz@linaro.org> wrote: > The kbuild test robot reported: > > drivers/staging/android/ion/ion_system_heap.c:122 alloc_largest_available() error: potential null dereference 'info'. (kmalloc returns null) > > Where the pointer returned from kmalloc goes unchecked for failure. > > This patch checks the return for NULL, and reworks the logic, as > suggested by Colin, so we allocate the page_info structure first. > > Cc: Colin Cross <ccross@android.com> > Cc: Greg KH <gregkh@linuxfoundation.org> > Cc: Android Kernel Team <kernel-team@android.com> > Cc: kbuild test robot <fengguang.wu@intel.com> > Reported-by: kbuild test robot <fengguang.wu@intel.com> > Signed-off-by: John Stultz <john.stultz@linaro.org> > --- > drivers/staging/android/ion/ion_system_heap.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c > index 144b2272..7f07291 100644 > --- a/drivers/staging/android/ion/ion_system_heap.c > +++ b/drivers/staging/android/ion/ion_system_heap.c > @@ -108,6 +108,10 @@ static struct page_info *alloc_largest_available(struct ion_system_heap *heap, > struct page_info *info; > int i; > > + info = kmalloc(sizeof(struct page_info), GFP_KERNEL); > + if (!info) > + return NULL; > + > for (i = 0; i < num_orders; i++) { > if (size < order_to_size(orders[i])) > continue; > @@ -118,11 +122,12 @@ static struct page_info *alloc_largest_available(struct ion_system_heap *heap, > if (!page) > continue; > > - info = kmalloc(sizeof(struct page_info), GFP_KERNEL); > info->page = page; > info->order = orders[i]; > return info; > } > + kfree(info); > + > return NULL; > } >
Acked-by: Colin Cross <ccross@android.com>
| |