From: Gavrilov Ilia Ilia.Gavrilov@infotecs.ru
[ Upstream commit 5c3be3e0eb44b7f978bb6cbb20ad956adb93f736 ]
The 'olr' variable can't be negative when assigned the result of 'min_t' because all 'min_t' parameters are cast to unsigned int, and then the minimum one is chosen.
To fix the logic, check 'olr' as read from 'optlen', where the types of relevant variables are (signed) int.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Gavrilov Ilia Ilia.Gavrilov@infotecs.ru Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/ipmr.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index d5421c38c2aae..3ed9ed2bffd29 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -1581,9 +1581,11 @@ int ip_mroute_getsockopt(struct sock *sk, int optname, sockptr_t optval,
if (copy_from_sockptr(&olr, optlen, sizeof(int))) return -EFAULT; - olr = min_t(unsigned int, olr, sizeof(int)); if (olr < 0) return -EINVAL; + + olr = min_t(unsigned int, olr, sizeof(int)); + if (copy_to_sockptr(optlen, &olr, sizeof(int))) return -EFAULT; if (copy_to_sockptr(optval, &val, olr))