rds: Integer overflow in RDS cmsg handling
In rds_cmsg_rdma_args(), the user-provided args->nr_local value is
restricted to less than UINT_MAX. This seems to need a tighter upper
bound, since the calculation of total iov_size can overflow, resulting
in a small sock_kmalloc() allocation. This would probably just result
in walking off the heap and crashing when calling rds_rdma_pages() with
a high count value. If it somehow doesn't crash here, then memory
corruption could occur soon after.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/rds/rdma.c b/net/rds/rdma.c
index 8920f2a..4e37c1c 100644
--- a/net/rds/rdma.c
+++ b/net/rds/rdma.c
@@ -567,7 +567,7 @@
goto out;
}
- if (args->nr_local > (u64)UINT_MAX) {
+ if (args->nr_local > UIO_MAXIOV) {
ret = -EMSGSIZE;
goto out;
}