diff --git a/sys/compat/linux/linux_misc.c b/sys/compat/linux/linux_misc.c
index f271482032fe..56b20f33c21c 100644
--- a/sys/compat/linux/linux_misc.c
+++ b/sys/compat/linux/linux_misc.c
@@ -989,7 +989,7 @@ linux_setgroups(struct thread *td, struct linux_setgroups_args *args)
 	struct proc *p;
 
 	ngrp = args->gidsetsize;
-	if (ngrp >= NGROUPS)
+	if (ngrp < 0 || ngrp >= NGROUPS)
 		return (EINVAL);
 	error = copyin(args->grouplist, linux_gidset, ngrp * sizeof(l_gid_t));
 	if (error)
diff --git a/sys/compat/linux/linux_uid16.c b/sys/compat/linux/linux_uid16.c
index 39dbfcd1e10a..06318eb3d8dd 100644
--- a/sys/compat/linux/linux_uid16.c
+++ b/sys/compat/linux/linux_uid16.c
@@ -100,7 +100,7 @@ linux_setgroups16(struct thread *td, struct linux_setgroups16_args *args)
 #endif
 
 	ngrp = args->gidsetsize;
-	if (ngrp >= NGROUPS)
+	if (ngrp < 0 || ngrp >= NGROUPS)
 		return (EINVAL);
 	error = copyin(args->gidset, linux_gidset, ngrp * sizeof(l_gid16_t));
 	if (error)