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mtd: Fix warning in access_ok() parameter passing

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On m68k, where access_ok() doesn't cast the address parameter:

drivers/mtd/mtdchar.c: In function 'mtdchar_write_ioctl':
drivers/mtd/mtdchar.c:575:4: warning: passing argument 2 of 'access_ok' makes pointer from integer without a cast [enabled by default]
arch/m68k/include/asm/uaccess_mm.h:17:90: note: expected 'const void *' but argument is of type '__u64'
drivers/mtd/mtdchar.c:576:4: warning: passing argument 2 of 'access_ok' makes pointer from integer without a cast [enabled by default]
arch/m68k/include/asm/uaccess_mm.h:17:90: note: expected 'const void *' but argument is of type '__u64'

The address parameter of access_ok() is really a userspace pointer.
On most architectures, access_ok() is a macro that casts the address
parameter, hiding issues in its users.

Move around and use the existing usr_data and usr_oob temporary variables
to kill the warnings. Add a few "consts", and make more use of the
temporaries while we're at it.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
This commit is contained in:
Geert Uytterhoeven 2014-05-01 20:40:54 +02:00 committed by Brian Norris
parent f306e8c3b6
commit f62cde49f9
1 changed files with 11 additions and 9 deletions
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20
drivers/mtd/mtdchar.c
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@ -568,13 +568,18 @@ static int mtdchar_write_ioctl(struct mtd_info *mtd,
{
struct mtd_write_req req;
struct mtd_oob_ops ops;
void __user *usr_data, *usr_oob;
const void __user *usr_data, *usr_oob;
int ret;
if (copy_from_user(&req, argp, sizeof(req)) ||
!access_ok(VERIFY_READ, req.usr_data, req.len) ||
!access_ok(VERIFY_READ, req.usr_oob, req.ooblen))
if (copy_from_user(&req, argp, sizeof(req)))
return -EFAULT;
usr_data = (const void __user *)(uintptr_t)req.usr_data;
usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
if (!access_ok(VERIFY_READ, usr_data, req.len) ||
!access_ok(VERIFY_READ, usr_oob, req.ooblen))
return -EFAULT;
if (!mtd->_write_oob)
return -EOPNOTSUPP;
@ -583,10 +588,7 @@ static int mtdchar_write_ioctl(struct mtd_info *mtd,
ops.ooblen = (size_t)req.ooblen;
ops.ooboffs = 0;
usr_data = (void __user *)(uintptr_t)req.usr_data;
usr_oob = (void __user *)(uintptr_t)req.usr_oob;
if (req.usr_data) {
if (usr_data) {
ops.datbuf = memdup_user(usr_data, ops.len);
if (IS_ERR(ops.datbuf))
return PTR_ERR(ops.datbuf);
@ -594,7 +596,7 @@ static int mtdchar_write_ioctl(struct mtd_info *mtd,
ops.datbuf = NULL;
}
if (req.usr_oob) {
if (usr_oob) {
ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
if (IS_ERR(ops.oobbuf)) {
kfree(ops.datbuf);