linux-imx

IB/hfi1: Fix NULL pointer dereference when invalid num_vls is used

When an invalid num_vls is used as a module parameter, the code
execution follows an exception path where the macro dd_dev_err()
expects dd->pcidev->dev not to be NULL in hfi1_init_dd(). This
causes a NULL pointer dereference.

Fix hfi1_init_dd() by initializing dd->pcidev and dd->pcidev->dev
earlier in the code. If a dd exists, then dd->pcidev and
dd->pcidev->dev always exists.

BUG: unable to handle kernel NULL pointer dereference
at 00000000000000f0
IP: __dev_printk+0x15/0x90
Workqueue: events work_for_cpu_fn
RIP: 0010:__dev_printk+0x15/0x90
Call Trace:
 dev_err+0x6c/0x90
 ? hfi1_init_pportdata+0x38d/0x3f0 [hfi1]
 hfi1_init_dd+0xdd/0x2530 [hfi1]
 ? pci_conf1_read+0xb2/0xf0
 ? pci_read_config_word.part.9+0x64/0x80
 ? pci_conf1_write+0xb0/0xf0
 ? pcie_capability_clear_and_set_word+0x57/0x80
 init_one+0x141/0x490 [hfi1]
 local_pci_probe+0x3f/0xa0
 work_for_cpu_fn+0x10/0x20
 process_one_work+0x152/0x350
 worker_thread+0x1cf/0x3e0
 kthread+0xf5/0x130
 ? max_active_store+0x80/0x80
 ? kthread_bind+0x10/0x10
 ? do_syscall_64+0x6e/0x1a0
 ? SyS_exit_group+0x10/0x10
 ret_from_fork+0x35/0x40

Cc: <stable@vger.kernel.org> # 4.9.x
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>