ipv4: potential underflow in compat_ip_setsockopt()

The value of "n" is capped at 0x1ffffff but it checked for negative
values.  I don't think this causes a problem but I'm not certain and
it's harmless to prevent it.

Fixes: 2e04172875 ("ipv4: do compat setsockopt for MCAST_MSFILTER directly")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Dan Carpenter 2020-05-23 20:46:48 +03:00 committed by David S. Miller
parent ca23cb0bc5
commit 6a1015b0b4

View File

@ -1347,8 +1347,8 @@ int compat_ip_setsockopt(struct sock *sk, int level, int optname,
{
const int size0 = offsetof(struct compat_group_filter, gf_slist);
struct compat_group_filter *gf32;
unsigned int n;
void *p;
int n;
if (optlen < size0)
return -EINVAL;