mtd: Fix warning in access_ok() parameter passing (f62cde49) · Commits · 戴 / test

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>

drivers/mtd/mtdchar.c

+11 −9

Original line number	Diff line number	Diff line
		@@ -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);

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