diff options
| author | Zev Weiss <zevweiss@gmail.com> | 2008-09-01 05:02:12 -0700 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2008-09-02 09:29:05 +0100 |
| commit | b67c5f87c13f398ec3f4d6b455cb0bbeda8d7ac0 (patch) | |
| tree | fc2ebe12c5b34439b9034742f957177111409cc7 /drivers/mtd | |
| parent | 02c0267a40c876a4d70f2000f21fe9ff89fb988e (diff) | |
| download | lwn-b67c5f87c13f398ec3f4d6b455cb0bbeda8d7ac0.tar.gz lwn-b67c5f87c13f398ec3f4d6b455cb0bbeda8d7ac0.zip | |
[MTD] mtdchar.c: Fix regression in MEMGETREGIONINFO ioctl()
The MEMGETREGIONINFO ioctl() in mtdchar.c was clobbering user memory by
overwriting more than intended, due the size of struct mtd_erase_region_info
changing in commit 0ecbc81adfcb9f15f86b05ff576b342ce81bbef8 ('Support
for auto locking flash on power up').
Fix avoids this by copying struct members one by one with put_user(), as there
is no longer a convenient struct to use the size of as the length argument to
copy_to_user().
Signed-off-by: Zev Weiss <zevweiss@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/mtdchar.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c index d2f331876e4c..e00d424e6575 100644 --- a/drivers/mtd/mtdchar.c +++ b/drivers/mtd/mtdchar.c @@ -410,16 +410,20 @@ static int mtd_ioctl(struct inode *inode, struct file *file, case MEMGETREGIONINFO: { - struct region_info_user ur; + uint32_t ur_idx; + struct mtd_erase_region_info *kr; + struct region_info_user *ur = (struct region_info_user *) argp; - if (copy_from_user(&ur, argp, sizeof(struct region_info_user))) + if (get_user(ur_idx, &(ur->regionindex))) return -EFAULT; - if (ur.regionindex >= mtd->numeraseregions) - return -EINVAL; - if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]), - sizeof(struct mtd_erase_region_info))) + kr = &(mtd->eraseregions[ur_idx]); + + if (put_user(kr->offset, &(ur->offset)) + || put_user(kr->erasesize, &(ur->erasesize)) + || put_user(kr->numblocks, &(ur->numblocks))) return -EFAULT; + break; } |