From c659395935d6ad8781fe9958ed1a9dbe969b3a17 Mon Sep 17 00:00:00 2001 From: Jesper Juhl Date: Sat, 28 Jan 2012 21:41:52 -0300 Subject: [PATCH] [media] tm6000: Don't use pointer after freeing it in tm6000_ir_fini() In tm6000_ir_fini() there seems to be a problem. rc_unregister_device(ir->rc); calls rc_free_device() on the pointer it is given, which frees it. Subsequently the function does: if (!ir->polling) __tm6000_ir_int_stop(ir->rc); and __tm6000_ir_int_stop() dereferences the pointer it is given, which has already been freed. and it also does: tm6000_ir_stop(ir->rc); which also dereferences the (already freed) pointer. So, it seems that the call to rc_unregister_device() should be move below the calls to __tm6000_ir_int_stop() and tm6000_ir_stop(), so those don't operate on a already freed pointer. But, I must admit that I don't know this code *at all*, so someone who knows the code should take a careful look before applying this patch. It is based purely on inspection of facts of what is beeing freed where and not at all on understanding what the code does or why. I don't even have a means to test it, so beyond testing that the change compiles it has seen no testing what-so-ever. Anyway, here's a proposed patch. Signed-off-by: Jesper Juhl Reviewed-by: Thierry Reding Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/tm6000/tm6000-input.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/media/video/tm6000/tm6000-input.c b/drivers/media/video/tm6000/tm6000-input.c index 7844607dd45a..859eb90e4d56 100644 --- a/drivers/media/video/tm6000/tm6000-input.c +++ b/drivers/media/video/tm6000/tm6000-input.c @@ -481,8 +481,6 @@ int tm6000_ir_fini(struct tm6000_core *dev) dprintk(2, "%s\n",__func__); - rc_unregister_device(ir->rc); - if (!ir->polling) __tm6000_ir_int_stop(ir->rc); @@ -492,6 +490,7 @@ int tm6000_ir_fini(struct tm6000_core *dev) tm6000_flash_led(dev, 0); ir->pwled = 0; + rc_unregister_device(ir->rc); kfree(ir); dev->ir = NULL; -- 2.20.1