[PATCH net-next] ipmr: fix incorrect parameter validation in the ip_mroute_getsockopt() function
From: Gavrilov Ilia <hidden>
Date: 2024-03-06 09:58:05
Also in:
lkml
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
The 'olr' variable can't be negative because all 'min_t' parameters
cast to unsigned int, and then the minimum one is chosen.
To fix it, move the if statement higher.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Gavrilov Ilia <redacted>
---
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 362229836510..b53c36c473a5 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c@@ -1603,9 +1603,11 @@ 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))
--
2.39.2