linux/drivers/media
Laurent Pinchart f41ced8f10 Check fops_get() return value
Several subsystem open handlers dereference the fops_get() return value
without checking it for nullness.  This opens a race condition between the
open handler and module unloading.

A module can be marked as being unloaded (MODULE_STATE_GOING) before its
exit function is called and gets the chance to unregister the driver.
During that window open handlers can still be called, and fops_get() will
fail in try_module_get() and return a NULL pointer.

This change checks the fops_get() return value and returns -ENODEV if NULL.

Reported-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Acked-by: Takashi Iwai <tiwai@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:11 -08:00
..
common V4L/DVB (10170): tuner-simple: prevent possible OOPS caused by divide by zero error 2009-01-02 17:15:18 -02:00
dvb Check fops_get() return value 2009-01-06 15:59:11 -08:00
radio V4L/DVB (10157): Add USB ID for the Sil4701 radio from DealExtreme 2009-01-02 17:13:56 -02:00
video V4L/DVB (10173): Missing v4l2_prio_close in radio_release 2009-01-03 10:50:38 -02:00
Kconfig V4L/DVB (8392): media/Kconfig: Convert V4L1_COMPAT select into "depends on" 2008-07-20 07:28:49 -03:00
Makefile V4L/DVB (8274): sms1xxx: build cleanup after driver relocation 2008-07-20 07:20:56 -03:00