[PATCH 3.16 115/136] netfilter: ipset: Fix an error code in ip_set_sockfn_get()

From: Ben Hutchings
Date: Mon Dec 16 2019 - 19:54:55 EST


3.16.80-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 30b7244d79651460ff114ba8f7987ed94c86b99a upstream.

The copy_to_user() function returns the number of bytes remaining to be
copied. In this code, that positive return is checked at the end of the
function and we return zero/success. What we should do instead is
return -EFAULT.

Fixes: a7b4f989a629 ("netfilter: ipset: IP set core support")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
net/netfilter/ipset/ip_set_core.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -1860,8 +1860,9 @@ ip_set_sockfn_get(struct sock *sk, int o
}

req_version->version = IPSET_PROTOCOL;
- ret = copy_to_user(user, req_version,
- sizeof(struct ip_set_req_version));
+ if (copy_to_user(user, req_version,
+ sizeof(struct ip_set_req_version)))
+ ret = -EFAULT;
goto done;
}
case IP_SET_OP_GET_BYNAME: {
@@ -1918,7 +1919,8 @@ ip_set_sockfn_get(struct sock *sk, int o
} /* end of switch(op) */

copy:
- ret = copy_to_user(user, data, copylen);
+ if (copy_to_user(user, data, copylen))
+ ret = -EFAULT;

done:
vfree(data);