[PATCH] staging: comedi: remove __user annotation inside of struct's

From: H Hartley Sweeten
Date: Tue May 08 2012 - 19:41:16 EST


The structs' comedi_insn, coomedi_insnlist, comedi_cmd,
comedi_chaninfo, and comedi_rangeinfo are all passed to
the kernel from user space using ioctl commands. They
are then copied to kernel space using copy_from_user()
before the data is passed to the drivers.

The __user annotation should not be used with variables
inside the struct. This produces a lot of sparse warnings
like:

warning: dereference of noderef expression

Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Mori Hess <fmhess@xxxxxxxxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---

Note: This patch exposes some new warnings about different
address space. These will be addressed.

diff --git a/drivers/staging/comedi/comedi.h b/drivers/staging/comedi/comedi.h
index 8ea55ae..2e2f366 100644
--- a/drivers/staging/comedi/comedi.h
+++ b/drivers/staging/comedi/comedi.h
@@ -335,7 +335,7 @@
struct comedi_insn {
unsigned int insn;
unsigned int n;
- unsigned int __user *data;
+ unsigned int *data;
unsigned int subdev;
unsigned int chanspec;
unsigned int unused[3];
@@ -343,7 +343,7 @@

struct comedi_insnlist {
unsigned int n_insns;
- struct comedi_insn __user *insns;
+ struct comedi_insn *insns;
};

struct comedi_cmd {
@@ -365,24 +365,24 @@
unsigned int stop_src;
unsigned int stop_arg;

- unsigned int __user *chanlist; /* channel/range list */
+ unsigned int *chanlist; /* channel/range list */
unsigned int chanlist_len;

- short __user *data; /* data list, size depends on subd flags */
+ short *data; /* data list, size depends on subd flags */
unsigned int data_len;
};

struct comedi_chaninfo {
unsigned int subdev;
- unsigned int __user *maxdata_list;
- unsigned int __user *flaglist;
- unsigned int __user *rangelist;
+ unsigned int *maxdata_list;
+ unsigned int *flaglist;
+ unsigned int *rangelist;
unsigned int unused[4];
};

struct comedi_rangeinfo {
unsigned int range_type;
- void __user *range_ptr;
+ void *range_ptr;
};

struct comedi_krange {
--
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