Messages in this thread | | | Date | Mon, 25 Dec 2006 18:58:29 +0900 | From | Akinobu Mita <> | Subject | Re: [PATCH -mm] ehca: avoid crash on kthread_create() failure |
| |
On Mon, Dec 25, 2006 at 11:41:32AM +0200, Muli Ben-Yehuda wrote: > On Mon, Dec 25, 2006 at 06:35:57PM +0900, Akinobu Mita wrote: > > On Mon, Dec 25, 2006 at 10:55:51AM +0200, Muli Ben-Yehuda wrote: > > > This is correct because cct is allocated via alloc_percpu, which in > > > turn calls kzalloc, which means cct->task is NULL by default, but it's > > > a little too obscure for me. How about making it explicit? > > > > > > task = kthread_create(...) > > > if (!IS_ERR(task)) > > > cct->task = task; > > > else > > > cct->task = NULL; > > > > > > return cct->task; > > > > Subject: [PATCH -mm] ehca: avoid crash on kthread_create() failure (v3) > > > > This patch disallows invalid task_struct pointer returned by > > kthread_create() to be written to percpu data to avoid crash. > > > > Cc: Heiko Carstens <heiko.carstens@de.ibm.com> > > Cc: Hoang-Nam Nguyen <hnguyen@de.ibm.com> > > Cc: Christoph Raisch <raisch@de.ibm.com> > > Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> > > > > --- > > drivers/infiniband/hw/ehca/ehca_irq.c | 11 ++++++++--- > > 1 file changed, 8 insertions(+), 3 deletions(-) > > > > Index: 2.6-mm/drivers/infiniband/hw/ehca/ehca_irq.c > > =================================================================== > > --- 2.6-mm.orig/drivers/infiniband/hw/ehca/ehca_irq.c > > +++ 2.6-mm/drivers/infiniband/hw/ehca/ehca_irq.c > > @@ -606,15 +606,20 @@ static int comp_task(void *__cct) > > static struct task_struct *create_comp_task(struct ehca_comp_pool *pool, > > int cpu) > > { > > + struct task_struct *task; > > struct ehca_cpu_comp_task *cct; > > > > cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu); > > spin_lock_init(&cct->task_lock); > > INIT_LIST_HEAD(&cct->cq_list); > > init_waitqueue_head(&cct->wait_queue); > > - cct->task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu); > > + task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu); > > + if (!IS_ERR(task)) > > + cct->task = task; > > + else > > + cct->task = NULL; > > > > - return cct->task; > > + return task; > > This should be return cct->task, since we later test the return value > of create_comp_task against NULL, e.g., in comp_poll_callback and > ehca_create_comp_pool.
Yeah, I already sent the patch: http://lkml.org/lkml/2006/12/19/56
Maybe I should reorganize these ehca fixes later. (make ehca_create_task() return NULL on failure)
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |