diff options
Diffstat (limited to 'drivers/mtd/mtdchar.c')
| -rw-r--r-- | drivers/mtd/mtdchar.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c index 7d4e7b9da3a1..a0f54e80670c 100644 --- a/drivers/mtd/mtdchar.c +++ b/drivers/mtd/mtdchar.c @@ -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); |