[PATCH 2/2] i2o: check return code from put_user()

From: Kulikov Vasiliy
Date: Thu Jul 15 2010 - 02:42:57 EST


Check return value of put_user() and return -EFAULT if it failed.
Original comment "We did a get user...so assuming mem is ok...is this
bad?" is incorrect because memory can be read only.

Signed-off-by: Kulikov Vasiliy <segooon@xxxxxxxxx>
---
drivers/message/i2o/i2o_config.c | 16 +++++++++-------
1 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/message/i2o/i2o_config.c b/drivers/message/i2o/i2o_config.c
index 4dd39a0..068ba07 100644
--- a/drivers/message/i2o/i2o_config.c
+++ b/drivers/message/i2o/i2o_config.c
@@ -111,9 +111,9 @@ static int i2o_cfg_gethrt(unsigned long arg)

len = 8 + ((hrt->entry_len * hrt->num_entries) << 2);

- /* We did a get user...so assuming mem is ok...is this bad? */
- put_user(len, kcmd.reslen);
- if (len > reslen)
+ if (put_user(len, kcmd.reslen))
+ ret = -EFAULT;
+ else if (len > reslen)
ret = -ENOBUFS;
else if (copy_to_user(kcmd.resbuf, (void *)hrt, len))
ret = -EFAULT;
@@ -147,8 +147,9 @@ static int i2o_cfg_getlct(unsigned long arg)
lct = (i2o_lct *) c->lct;

len = (unsigned int)lct->table_size << 2;
- put_user(len, kcmd.reslen);
- if (len > reslen)
+ if (put_user(len, kcmd.reslen))
+ ret = -EFAULT;
+ else if (len > reslen)
ret = -ENOBUFS;
else if (copy_to_user(kcmd.resbuf, lct, len))
ret = -EFAULT;
@@ -208,8 +209,9 @@ static int i2o_cfg_parms(unsigned long arg, unsigned int type)
return -EAGAIN;
}

- put_user(len, kcmd.reslen);
- if (len > reslen)
+ if (put_user(len, kcmd.reslen))
+ ret = -EFAULT;
+ else if (len > reslen)
ret = -ENOBUFS;
else if (copy_to_user(kcmd.resbuf, res, len))
ret = -EFAULT;
--
1.7.0.4

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