[PATCH 5.10 228/563] netrom: fix api breakage in nr_setsockopt()

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 16:13:36 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit dc35616e6c2907b0c0c391a205802d8880f7fd85 ]

This needs to copy an unsigned int from user space instead of a long to
avoid breaking user space with an API change.

I have updated all the integer overflow checks from ULONG to UINT as
well. This is a slight API change but I do not expect it to affect
anything in real life.

Fixes: 3087a6f36ee0 ("netrom: fix copying in user data in nr_setsockopt")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/netrom/af_netrom.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c
index eef0e3f2f25b0..e5c8a295e6406 100644
--- a/net/netrom/af_netrom.c
+++ b/net/netrom/af_netrom.c
@@ -298,7 +298,7 @@ static int nr_setsockopt(struct socket *sock, int level, int optname,
{
struct sock *sk = sock->sk;
struct nr_sock *nr = nr_sk(sk);
- unsigned long opt;
+ unsigned int opt;

if (level != SOL_NETROM)
return -ENOPROTOOPT;
@@ -306,18 +306,18 @@ static int nr_setsockopt(struct socket *sock, int level, int optname,
if (optlen < sizeof(unsigned int))
return -EINVAL;

- if (copy_from_sockptr(&opt, optval, sizeof(unsigned long)))
+ if (copy_from_sockptr(&opt, optval, sizeof(opt)))
return -EFAULT;

switch (optname) {
case NETROM_T1:
- if (opt < 1 || opt > ULONG_MAX / HZ)
+ if (opt < 1 || opt > UINT_MAX / HZ)
return -EINVAL;
nr->t1 = opt * HZ;
return 0;

case NETROM_T2:
- if (opt < 1 || opt > ULONG_MAX / HZ)
+ if (opt < 1 || opt > UINT_MAX / HZ)
return -EINVAL;
nr->t2 = opt * HZ;
return 0;
@@ -329,13 +329,13 @@ static int nr_setsockopt(struct socket *sock, int level, int optname,
return 0;

case NETROM_T4:
- if (opt < 1 || opt > ULONG_MAX / HZ)
+ if (opt < 1 || opt > UINT_MAX / HZ)
return -EINVAL;
nr->t4 = opt * HZ;
return 0;

case NETROM_IDLE:
- if (opt > ULONG_MAX / (60 * HZ))
+ if (opt > UINT_MAX / (60 * HZ))
return -EINVAL;
nr->idle = opt * 60 * HZ;
return 0;
--
2.34.1