From a2e7014b35db02838c9bd4051e2e188e84376d0a Mon Sep 17 00:00:00 2001 From: Gavrilov Ilia Date: Thu, 7 Mar 2024 14:23:50 +0000 Subject: [PATCH] ipmr: fix incorrect parameter validation in the ip_mroute_getsockopt() function [ 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 Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- 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 cdc0a1781..db184cb82 100755 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -1574,9 +1574,11 @@ 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))