linux/drivers/hwtracing/intel_th
Alexander Shishkin 8fd0d85368 intel_th: Fix a NULL dereference when hub driver is not loaded
commit e78e1fdb28 upstream.

Connecting master to an output port when GTH driver module is not loaded
triggers a NULL dereference:

> RIP: 0010:intel_th_set_output+0x35/0x70 [intel_th]
> Call Trace:
>  ? sth_stm_link+0x12/0x20 [intel_th_sth]
>  stm_source_link_store+0x164/0x270 [stm_core]
>  dev_attr_store+0x17/0x30
>  sysfs_kf_write+0x3e/0x50
>  kernfs_fop_write+0xda/0x1b0
>  __vfs_write+0x1b/0x40
>  vfs_write+0xb9/0x1a0
>  ksys_write+0x67/0xe0
>  __x64_sys_write+0x1a/0x20
>  do_syscall_64+0x57/0x1d0
>  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Make sure the module in question is loaded and return an error if not.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 39f4034693 ("intel_th: Add driver infrastructure for Intel(R) Trace Hub devices")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reported-by: Ammy Yi <ammy.yi@intel.com>
Tested-by: Ammy Yi <ammy.yi@intel.com>
Cc: stable@vger.kernel.org # v4.4
Link: https://lore.kernel.org/r/20200706161339.55468-5-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-22 09:33:15 +02:00
..
Kconfig
Makefile
acpi.c
core.c intel_th: Fix a NULL dereference when hub driver is not loaded 2020-07-22 09:33:15 +02:00
debug.c
debug.h
gth.c
gth.h
intel_th.h
msu-sink.c
msu.c intel_th: Fix user-visible error codes 2020-03-25 08:25:55 +01:00
msu.h
pci.c intel_th: pci: Add Emmitsburg PCH support 2020-07-22 09:33:15 +02:00
pti.c
pti.h
sth.c intel_th: Fix a NULL dereference when hub driver is not loaded 2020-07-22 09:33:15 +02:00
sth.h